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Refrigerator Repair

at room temperature, some of them will spoil rapidly. When foods are kept cold,

they will last longer. Refrigerators prevent food spoilage by keeping the food cold.

The refrigerator consists of three parts:

compressor, and the connecting tubing.

This chapter covers the electrical components and how to diagnose the sealed system.

The actual repair or replacement of any sealed-system component is not included in this

chapter. It is recommended that you acquire refrigerant certification (or call an authorized

service company) to repair or replace any sealed-system component. The refrigerant in the

sealed system must be recovered properly.

The Refrigeration Cycle

The sealed system (Figure 25-1) in a refrigerator consists of a compressor, a condenser coil,

an evaporator coil, a capillary tube, and a heat exchanger and its connecting tubing. This is

the heart of the refrigerator that keeps the food cold inside the cabinet.

Starting at the compressor, refrigerant gas is pumped out of the compressor, through the

discharge tubing, and into the condenser coil. When the gas is in the condenser coil, the

temperature and pressure of the refrigerant gas greatly increase because of the capillary

tube at the discharge end of the condenser coil. From the surface of the condenser coil, the

heat spreads out into the room via air moving over the condenser coil. The condenser coil

cools the hot refrigerant gas. As the refrigerant gas gives up the heat it obtained from inside

the refrigerator cabinet, the refrigerant gas changes into a liquid. This liquid then leaves the

condenser coil and enters the capillary tube.

This capillary tube is carefully made with regard to its length and inside diameter to

meter out the exact amount of liquid refrigerant through the sealed system (this is designed

by the manufacturer for a particular size and model). As the liquid refrigerant leaves the

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CHAPTER

capillary tube and enters the larger tubing of

the evaporator coil, the sudden increase of

tubing size causes a low-pressure area. It is

here that the liquid refrigerant changes from a

liquid to a mixture of liquid and gas.

As this mixture passes through the

evaporator coil, the refrigerant absorbs heat

from the warmer items (food) within the

refrigerator cabinet, slowly changing any

liquid back to gas. As the refrigerant gas leaves

the evaporator coil, it returns to the compressor

through the suction line.

Depending on where the cold control

(thermostat) is set, the thermostat can show

how cold it is inside the cabinet and then

control the actuation of the cooling cycle. It will

determine whether to turn the system on or off

to maintain the temperature within the cabinet.

Inside the cabinet, the cold air is circulated

by convection and/or by means of an electrical

fan. In Figure 25-2, the arrows show the airflow

patterns in this type of side-by-side refrigerator. Figure 25-3 shows the air patterns in a

two-door refrigerator with a top freezer.

FIGURE 25-1

The sealed-system

components in a sideby-

side refrigerator.

Capillary tube

Evaporator

Suction line

Compressor

Condenser

Heat exchanger

Discharge line

Around meat

keeper

refrigerator.

PART VI

Refrigerator Automatic Defrost Systems

Over the years manufacturers have developed many methods to defrost the evaporator coil.

Maintaining proper moisture control within the refrigerator is crucial for proper efficient

operation. Every time the consumer opens the door, moisture and heat enter the refrigerator

compartment. Through either natural convection or forced-air movement, the moisture will

eventually condense on the coldest spot in the refrigerator: the evaporator coil. The

evaporator coil is well below the freezing temperatures, and the condensed moisture will

stick to it and begin to freeze. As frost accumulates on the evaporator coil, the airflow

through the evaporator coil will begin to decease and the cooling effect will also decrease.

The manual method for defrosting an evaporator coil will be time consuming, and most

consumers end up destroying the evaporator coil by punching a hole in it with an ice pick

or a knife. Manufacturers have developed the automatic defrost system. Most modern-day

refrigerators have a timer to activate the defrost cycle. A heater element and a defrost

termination thermostat have also been attached to the evaporator coil to defrost the frost

buildup. When the timer calls for the defrost cycle, the sealed system is de-energized and

the heater is energized. The defrost termination thermostat monitors the temperature of the

evaporator coil; at around 40 to 60 degrees Fahrenheit the thermostat will turn off the heater.

The defrost timer will stay in the defrost mode for up to 30 minutes, regardless of whether

the frost is melted or not. The water that results from the defrost process will be directed

to the evaporator drain pan and then redirected to the outside of the refrigerator to the

condensate pan at the base of the refrigerator to be evaporated.

FIGURE 25-3

The airlow pattern in

a two-door refrigerator

with top freezer.

Some refrigerator models use a defrost cycle on a timed schedule. That means

approximately every six to eight hours, the defrost cycle is turned on for approximately 28

to 30 minutes. This type of defrosting system runs without regard for the actual cooling

demand on the sealed system. A more efficient type of defrost system developed by

manufacturers is the cumulative run-time defrost system. This type of system is based on

the compressor run time. The defrost timer only advances when the compressor run time

has equaled a predetermined amount of run time; then the system will enter into a defrost

time. One disadvantage of this type of defrost system is it does not account for the number

of times the door is opened and the increased humidity enters the refrigerator compartment.

Manufacturers over time have developed a new type of automatic defrost system: the

adaptive automatic defrost system. With the decreased cost of electronic components a

better way has been developed to control the defrost frequency. This type of system

measures the time it takes from the start of the defrost cycle until the defrost termination

thermostat opens. This type of system is known as adaptive defrost.

Depending on the manufacturer, the first defrost time will occur between six to eight

hours of cumulative compressor run time. The adaptive defrost control (ADC) will

continually adjust the defrost intervals based on the following:

During the defrost cycle, the ADC monitors how long the defrost termination thermostat

keeps the heater energized. If the defrost termination thermostat opens in under 12 minutes,

this is equal to a light frost buildup. The ADC will increase the amount of compressor run

time between defrost times by two hours. If the defrost termination thermostat opens in over

12 minutes, this is equal to a heavier frost buildup. The ADC will decrease the amount of

compressor run time between defrost times by two hours.

Over the course of several defrost cycles, the time between the start of the defrost cycle

and the opening of the defrost termination thermostat will get closer to the ideal defrost

time. The ADC has adjusted the amount of run time between defrosts to occur often enough

to maintain a clean evaporator coil, but not so often as to use excessive energy. As humidity

conditions change and the frost load increases or decreases, the ADC will adjust the

cumulative run time to match the change in the frost load.

As mentioned earlier, not all refrigerator manufacturers use this process. They use a

slightly different algorithm programmed into the ADC computer chip, but the principle of

operation for most of these ADC controls is very similar. The service technician will need

the wiring diagram and/or the service manual for the model they are servicing to properly

diagnose and be able to turn on the defrost mode on the ADC board.

Another type of defrost system is the hot gas defrost system. This type of system is seldom

used in residential refrigerators due to the additional cost of components. The hot gas defrost

systems are used in commercial ice machines to aid in the harvesting process of ice. In the

residential refrigerator, a bypass valve is added to the sealed system to the condenser at a

point before the refrigerant begins to condense into a liquid state. When defrost is called for,

the valve will open, and the hot gas enters the evaporator after the capillary tube inlet. The

hot gas will thaw the frost from the evaporator coil.

PART VI

A cycle defrost system is used on inexpensive refrigerators. The freezer evaporator is

manual defrost, but the refrigerator evaporator is defrosted every time the compressor

cycles off. In this type of system a special thermostat and two low-wattage heaters are used

to defrost the evaporator.

Storage Requirements for Perishable Products

Table 25-1 lists the recommended storage temperatures, relative humidity, and the

approximate storage life for perishable products. These values are used in designing

commercial refrigeration systems, which house large quantities of perishable products.

Product

Storage

Temp.° F

Relative

Humidity %

Approximate

Storage Life

Apples 30–40 90 3–8 months

Apricots 31–32 90 1–2 weeks

Artichokes 31–32 95 2 weeks

Asparagus 32–36 95 2–3 weeks

Avocados 45–55 85–90 2–4 weeks

Bananas 55–65 85–95 —

Beans (green or snap) 40–45 90–95 7–10 days

Beans, lima 32–40 90 1 week

Blackberries 31–32 95 3 days

Blueberries 31–32 90–95 2 weeks

Broccoli 32 95 10–14 days

Cabbage 32 95–100 3–4 months

Carrots 32 98–100 5–9 months

Cauliflower 32 95 2–4 weeks

Celery 32 95 1–2 months

Cherries, sour 31–32 90–95 3–7 days

Cherries, sweet 30–31 90–95 2–3 weeks

Collards 32 95 10–14 days

Corn, sweet (fresh) 32 95 4–8 days

Cranberries 36–40 90–95 2–4 months

Cucumbers 50–55 90–95 10–14 days

Dairy products

Cheddar cheese 40 65–70 6 months

Processed cheese 40 65–70 12 months

Product

Storage

Temp.° F

Relative

Humidity %

Approximate

Storage Life

Butter 40 75–85 1 month

Cream 35–40 — 2–3 weeks

Ice cream –20 to –15 — 3–12 months

Milk, fluid whole

Pasteurized, grade A 32–34 — 2–4 months

Condensed, sweetened 40 — 15 months

Evaporated 40 — 24 months

Dates (dried) 0 or 32 75 or less 6–12 months

Dried fruits 32 50–60 9–12 months

Eggplant 45–50 90–95 7–10 days

Eggs, shell 29–31 80–85 5–6 months

Figs, dried 32–40 50–60 9–12 months

Figs, fresh 31–32 85–90 7–10 days

Fish, fresh 30–35 90–95 5–15 days

Haddock, cod 30–35 90–95 15 days

Salmon 30–35 90–95 15 days

Smoked 40–50 50–60 6–8 months

Shellfish, fresh 30–33 86–95 3–7 days

Tuna 30–35 90–95 15 days

Grapefruit 50–60 85–90 4–6 weeks

Grapes, American type 31–32 85–90 2–8 weeks

Grapes, European type 30–31 90–95 3–6 months

Greens, leafy 32 95 10–14 days

Guavas 45–50 90 2–3 weeks

Honey 38–50 50–60 1 year, plus

Horseradish 30–32 95–100 10–12 months

Lemons 32 or 50–58 85–90 1–6 months

Lettuce, head 32–34 95–100 2–3 weeks

Limes 48–50 85–90 6–8 weeks

Maple sugar 75–80 60–65 1 year, plus

Mangoes 55 85–90 2–3 weeks

Meat

Bacon, cured (farm style) 60–65 85 4–6 months

Game, fresh 32 80–85 1–6 weeks

PART VI

Product

Storage

Temp.° F

Relative

Humidity %

Approximate

Storage Life

Beef, fresh 32–34 88–92 1–6 weeks

Hams and shoulders, fresh 32–34 85–90 7–12 days

Cured 60–65 50–60 0–3 years

Lamb, fresh 32–34 85–90 5–12 days

Livers, frozen –10–0 90–95 3–4 months

Pork, fresh 32–34 85–90 3–7 days

Smoked sausage 40–45 85–90 6 months

Fresh 32 85–90 1–2 weeks

Veal, fresh 32–34 90–95 5–10 days

Melons, Cantaloupe 36–40 90–95 5–15 days

Honeydew and Honey Ball 45–50 90–95 3–4 weeks

Watermelons 40–50 80–90 2–3 weeks

Mushrooms 32 90 3–4 days

Milk 34–40 — 7 days

Nectarines 31–32 90 2–4 weeks

Nuts (dried) 32–50 65–75 8–12 months

Okra 45–50 90–95 7–10 days

Olives, fresh 45–50 85–90 4–6 weeks

Onions (dry) and onion sets 32 65–70 1–8 months

Oranges 32–48 85–90 3–12 weeks

Orange juice, chilled 30–35 — 3–6 weeks

Papayas 45 85–90 1–3 weeks

Parsley 32 95 1–2 months

Parsnips 32 98–100 4–6 months

Peaches 31–32 90 2–4 weeks

Pears 29–31 90–95 2–7 months

Peas, green 32 95 1–3 weeks

Peppers, sweet 45–50 90–95 2–3 weeks

Pineapples, ripe 45 85–90 2–4 weeks

Plums, including fresh prunes 31–32 90–95 2–4 weeks

Popcorn, unpopped 32–40 85 4–6 months

Potatoes, early crop 50–55 90 0–2 months

Potatoes, late crop 38–50 90 5–8 months

Product

Storage

Temp.° F

Relative

Humidity %

Approximate

Storage Life

Poultry

Fresh chicken 32 85–90 1 week

Fresh goose 32 85–90 1 week

Fresh turkey 32 85–90 1 week

Pumpkins 50–55 70–75 2–3 months

Radishes—spring, prepacked 32 95 3–4 weeks

Raisins (dried) 40 60–70 9–12 months

Rabbits, fresh 32–34 90–95 1–5 days

Raspberries, black 31–32 90–95 2–3 days

Raspberries, red 31–32 90–95 2–3 days

Rhubarb 32 95 2–4 weeks

Spinach 32 95 10–14 days

Squash, summer 32–50 85–95 5–14 days

Squash, winter 50–55 70–75 4–6 months

Strawberries, fresh 31–32 90–95 5–7 days

Sugar, maple 75–80 60–65 1 year, plus

Sweet potatoes 55–60 85–90 4–7 months

Syrup, maple 31 60–70 1 year, plus

Tangerines 32–38 85–90 2–4 weeks

Tomatoes, mature green 55–70 85–90 1–3 weeks

Tomatoes, firm ripe 45–50 85–90 4–7 days

Turnips, roots 32 95 4–5 months

Vegetables (mixed) 32–40 90–95 1–4 weeks

Yams 60 85–90 3–6 months

Large warehouses are usually equipped to store foods at those temperatures best adapted to

prolonging the safe storage period for each type of food. In the domestic refrigerator, most

foods are kept at 34 to 40 degrees Fahrenheit (1 to 4 degrees Celsius) with an optimum

temperature of 37 degrees Fahrenheit, and the humidity is kept around 50 percent. The freezer

temperature is between zero and minus 10 degrees Fahrenheit (–17 to –23 degrees Celsius).

It can be difficult to maintain these temperatures and humidity for each individual

product. Therefore, refrigerator manufacturers have designed separate compartments

within the refrigerated cabinet to maintain a variable temperature and humidity selected by

the consumer. The storage life of various products will vary in a domestic refrigerator/

freezer (Table 25-2). This period will be influenced by many factors, such as the storage

PART VI

DOMESTIC REFRIGERATOR/FREEZER FOOD STORAGE TIPS

Foods Refrigerator Freezer Storage Tips

DAIRY PRODUCTS

Butter 1 month 6 to 9 months Wrap product tightly or cover.

Milk and cream 1 week Not recommended Check the date on the carton.

Close tightly. Do not store

unused portions in the original

container. Do not freeze the

cream unless whipped.

Cream cheese, cheese

spread, and cheese food

1 to 2 weeks Not recommended Wrap product tightly.

Cottage cheese 3 to 5 days Not recommended Keep product stored in original

carton. Check carton date.

Sour cream 10 days Not recommended Keep product stored in original

carton. Check carton date.

Hard cheese

(Swiss, Cheddar, and

Parmesan)

1 to 2

months

4 to 6 months

May become

crumbly

Wrap tightly.

Cut off mold.

EGGS

Eggs in the shell 3 weeks Not recommended Refrigerate with the small ends

facing down.

Leftover yolks or whites 2 to 4 days 9 to 12 months For each cup of yolks to be

frozen, add 1 teaspoon of sugar

for use in sweet dishes, or 1

teaspoon of salt for nonsweet

dishes.

FRUITS

Apples 1 month 8 months (cooked) Store unripe or hard apples at

60º to 70ºF (16º to 21ºC).

Bananas 2 to 4 days 6 months

(whole peeled)

Ripen at room temperature

before refrigerating. Bananas

will darken when refrigerated.

Pears, plums, avocados 3 to 4 days Not recommended Ripen at room temperature

before refrigerating. Avocados

will darken when refrigerated.

Berries, cherries, apricots 2 to 3 days 6 months Ripen at room temperature

before refrigerating.

Grapes 3 to 5 days 1 month (whole) Ripen at room temperature

before refrigerating.

Citrus fruits 1 to 2 weeks Not recommended Store uncovered at 60º to 70ºF

(16º to 21ºC).

DOMESTIC REFRIGERATOR/FREEZER FOOD STORAGE TIPS

Foods Refrigerator Freezer Storage Tips

Pineapples, cut 2 to 3 days 6 to 12 months Will not ripen after purchase.

Use quickly.

VEGETABLES

Asparagus 1 to 2 days 8 to 10 months Do not wash before

refrigerating. Store in crisper

drawer.

Brussels sprouts,

broccoli, cauliflower, green

peas, lima beans, onions,

peppers

3 to 5 days 8 to 10 months Wrap odorous foods. Leave the

peas in the pods.

Cabbage, celery 1 to 2 weeks Not recommended Wrap odorous foods and

refrigerate in crisper drawer.

Carrots, parsnips, beets,

turnips

7 to 10 days 8 to 10 months Remove tops. Wrap odorous

foods and refrigerate in crisper

drawer.

Lettuce 7 to 10 days Not recommended

POULTRY and FISH

Chicken and turkey, whole 1 to 2 days 12 months Keep in original packaging

for refrigeration. Place in the

meat and cheese drawer. When

freezing longer than two weeks,

overwrap with freezer wrap

paper.

Chicken and turkey,

pieces

1 to 2 days 9 months

Fish 1 to 2 days 2 to 6 months

MEATS

Bacon 7 days 1 month

Beef or lamb, ground 1 to 2 days 3 to 4 months Fresh meats can be kept

in original packaging for

refrigeration.

Beef or lamb, roast and

steak

3 to 5 days 6 to 9 months Place in the meat and cheese

drawer. When freezing longer

than two weeks, overwrap with

freezer wrap paper.

Ham, fully cooked, whole 7 days 1 to 2 months

Ham, fully cooked, half 5 days 1 to 2 months

Ham, fully cooked, slices 3 days 1 to 2 months

Luncheon meats 3 to 5 days 1 to 2 months Unopened, vacuum-packed

luncheon meat may be kept up

to two weeks in the meat and

cheese drawer.

PART VI

DOMESTIC REFRIGERATOR/FREEZER FOOD STORAGE TIPS

Foods Refrigerator Freezer Storage Tips

Pork, roast 3 to 5 days 4 to 6 months

Pork, chops 3 to 5 days 4 months

Sausage, ground 1 to 2 days 1 to 2 months

Veal 3 to 5 days 4 to 6 months

Frankfurters 7 days 1 month Processed meats should be

tightly wrapped and stored in

the meat and cheese drawer.

temperature, the type of container, the condition of the food, and the kind of food. For food

storage tips, consult the use and care guide.

To test the temperature in a refrigerator/freezer, place a thermometer in a glass of water

and place it in the center of the refrigerator compartment. After 24 hours, check the

thermometer. To test the temperature in the freezer compartment, place a thermometer

between two frozen packages. After 24 hours, check the thermometer. If the temperature

controls needs to be readjusted, retake temperatures as listed earlier.

Safety First

install, maintain, or repair any refrigerators. Any improper installation, preventive

maintenance, or repairs could create a risk of personal injury or property damage.

If you do not fully understand the installation, preventive maintenance, or repair procedures

in this chapter, or if you doubt your ability to complete the task on your refrigerator or freezer,

please call your service manager.

Before continuing, take a moment to refresh your memory of the safety procedures in

Chapter 2.

Refrigerators in General

Much of the troubleshooting information in this chapter covers refrigerators in general,

rather than specific models, in order to present a broad overview of service techniques. The

illustrations in this chapter are for demonstration purposes only, to clarify the description of

how to service these appliances. They in no way reflect on a particular brand’s reliability.

Location and Installation of Refrigerator

Thoroughly read the installation instructions that are provided with every new refrigerator.

These instructions will provide you with the information you need to properly install the

refrigerator. The following are some general principles that should be followed when

performing the installation:

up to 1000 pounds.

clearance at the rear and top of the cabinet and adequate clearance near the front

grille at the bottom of the refrigerator.

shipping base.

according to the installation instructions, and remember to realign the doors

properly.

What’s That “Different” Sound in Your Kitchen?

If you have bought or serviced a new refrigerator within the past few years, you’ve

probably noticed that it sounds “different.” Here’s why: New refrigerators use only half as

much electricity as the older models. In fact, a new 20.6-cubic foot refrigerator with top

freezer uses no more electricity than a 75-watt light bulb. Most new refrigerators are also

larger, and they have such added conveniences as automatic defrost systems, ice makers,

and perhaps even a “built-in” look. These new features result in different sounds, such as:

have smaller, higher-speed motors.

fan under the refrigerator.

thermostat turning the refrigerator on and off, or the water valve refilling the ice

maker.

the refrigerant continues to circulate within the system or the defrost water runs

into the drain pan.

the ice cubes drop into the storage bin.

To help mute these new sounds:

position (usually reachable behind the bottom front “toe plate”).

refrigerator.

designed as a “built-in” unit. Check your use and care manual for the needed space.

PART VI

To reduce the compressor run time:

large empty space.

The Major Appliance Consumer Action Panel, or MACAP, was an independent complaintmediation

group made up of professionals with expertise in textiles, equipment, consumer

law, and engineering who volunteered their time. Unfortunately, MACAP went out of

business in the last few years, but the information that is printed in this book is still valuable

and worth reading for guidance. If you are experiencing any problems with your product or

service company, contact your local Better Business Bureau (BBB).

Many of the consumers who filed “refrigerator sound” complaints with the MACAP

represent one- or two-family households; they have recently moved to smaller retirement

homes; or they have remodeled, and the kitchen is now open to a family living area. Sounds

are more noticeable in quieter surroundings. Consumers with hearing aids are especially

sensitive.

Some consumers reported to MACAP that their refrigerators are “louder” than an

identical model in a friend’s or a relative’s house. This might be because of the number of

people in the house, as well as different furnishings and room arrangements. Carpeting,

Are Refrigerators/Freezers Snowbirds?

Putting that extra refrigerator or freezer in any area in which the temperature falls below

60 degrees Fahrenheit might be a problem in colder areas when the winter months are

approaching. Combination refrigerator/freezers and freezers with automatic defrost systems

are sensitive to the ambient air temperature surrounding them. As this ambient temperature

rises, the compressor runs more to maintain the storage temperature in the fresh food and

frozen food compartments, thus wasting energy. As the ambient temperature falls, compressor

operation decreases.

When temperatures fall below 60 degrees Fahrenheit, the compressor will not operate

long enough to maintain low storage temperatures in the freezer compartment. This is

because the fresh food compartment contains the primary sensor, and it is satisfied quickly

at a low ambient temperature. The lower the temperature goes, the worse this condition

becomes. At about 38 to 42 degrees Fahrenheit, the compressor will not run at all. The

freezer compartment temperature will increase to the ambient room temperature, and the

frozen food in the compartment will defrost and spoil.

Combination refrigerator/freezers and automatic-defrost freezers should not be

operated in unheated places, like garages or porches, where room temperatures are likely to

drop below 60 degrees Fahrenheit, unless they are specifically designed for operation in low

temperatures. Check the manufacturer’s use and care manual for the lowest safe operating

temperature.

At any time the temperature will be less than 60 degrees Fahrenheit, it is best to empty the

freezer compartment of the refrigerator/freezer in order to prevent defrosting and the possible

spoilage of frozen foods. You might want to consider removing all of the food from the unit,

turning it off, and propping the door open if you will be absent for an extended period of time.

latch-type handle (pre-1958 model) because of the potential for child entrapment.

Manual-defrost freezers can usually be operated in an unheated garage or porch

without affecting the unit or the frozen food. However, check the use and care manual to

“Freezer” in Single-Door Refrigerator Has Limited Function

“I just bought a single-door refrigerator and my ice cream won’t harden. It’s like cold soup,”

a consumer recently complained to MACAP. “If I turn the temperature control to a colder

setting, the food in the refrigerator section freezes, but the ice cream remains soup. Something’s

wrong with the freezer.”

Approximately 6 percent of all refrigerators sold each year are “single-door” models.

That is, the model has only one outside door. Inside (usually across the top or to one side) is

a small freezer compartment with its own door. Most combination refrigerator/freezers

have two or more doors on the outside, providing independent access to separate freezer or

refrigerated sections.

In the course of investigating this consumer’s complaint, MACAP found that consumers

have reason to be confused about the capabilities of “single-door” refrigerators. Many

manufacturers refer to the separate frozen food compartment as a “freezer section,” as a

“freezer compartment,” or as a “freezer” in their specification literature. MACAP found that

a majority of consumers expect to be able to keep such hard-to-freeze items as ice cream and

orange juice in this “freezer” compartment. These items have a high sugar content, and they

freeze at lower temperatures than water.

The Association of Home Appliance Manufacturers (AHAM), in its nationally accepted

standard, calls such a unit a “basic refrigerator” and specifies that it is “intended for short-term

storage of foods at temperatures below 32 degrees Fahrenheit and normally above 8 degrees

Fahrenheit.” However, most newer models have temperatures at (or near) freezing level, which

is not adequate to freeze foods. Distilled water freezes at 32 degrees Fahrenheit, but all frozen

foods must be stored at a temperature lower than that to freeze. Vegetables begin to freeze at

29 to 31 degrees Fahrenheit, meats at 25 to 29 degrees Fahrenheit, and orange juice concentrate

at about 8 degrees Fahrenheit. Ice cream begins to stiffen at 27 degrees Fahrenheit, but is

considered at an ideal hardness for scooping at 8 degrees Fahrenheit.

If reference is made to the compartment being a “food freezer” or a “frozen food storage

compartment” (as in double-door units), the consumer can expect that it will store already

frozen foods for several days, or even months, without deterioration. However, a “freezer

section” or “freezer compartment,” as found in single-door refrigerators, might only freeze

ice cubes.

MACAP recommends that consumers determine their food freezing needs and carefully

Refrigerator Maintenance

The inside of the cabinet should be cleaned at least once a month to help prevent odors from

building up. Of course, any spills that might happen should be wiped up immediately.

Wash all removable parts by hand with warm water and a mild detergent; then rinse and

dry the parts. The inside walls of the cabinet, the door liners, and the gaskets should also be

washed using warm water and a mild detergent, rinsed, and dried. Never use cleaning

PART VI

waxes, concentrated detergents, bleaches, ammonia, or cleansers containing petroleum

products on plastic parts. Never use cleaning products with a lemon scent; the lemon will

be absorbed into the liner permanently and it may also affect the food. On the outside of the

cabinet, use a sponge with warm water and a mild detergent to clean dust and dirt. Then

rinse off and dry thoroughly.

At least two times a year, the outside cabinet should be waxed with an appliance wax or

with a good auto paste wax. Waxing painted metal surfaces provides rust protection. The

defrost pan, which is located behind the toe plate or behind the cabinet, should be cleaned

out once a month. The condenser coil should also be cleaned of dust and lint at least once a

month. The floor should be free of dirt and debris when the cabinet is rolled out away from

the wall. After the cabinet is rolled back into place, you must check to be sure that the

cabinet is level.

Food Odors and Molds

Odors in the refrigerator compartment or the freezer compartment cannot occur by

themselves. The only way that odors can occur is by storing foods in an unsealed container

or unwrapped. Another way that odors occur is from food spillage or from rotten or spoiled

food. In new refrigerators there may be a plastic odor, but this is normal and it will dissipate

in time. Here are some more tips to help in odor removal:

1. Place a box of baking soda in the refrigerator’s fresh food and freezer compartments.

Replace according to the instructions on the box.

2. Place some activated charcoal in a shallow metal pan inside the fresh food or the

freezer compartment of the refrigerator. When the charcoal loses its effectiveness,

place the metal pan in the oven and heat it on a low temperature for a couple of

hours to rejuvenate it. Do not use charcoal briquettes used for grilling; it is not the

same activated charcoal.

3. Place some vanilla extract in a small dish and place in the refrigerator’s fresh food

compartment for three weeks. Do not place in the freezer compartment; the vanilla

extract will freeze and be ineffective.

On occasion the ice cubes will have a bad taste and will smell like food. Sometimes, the

food odors come from the refrigerator compartment. To be able to tell which storage

compartment is producing the food odors, try the following:

1. Fill ice trays with tap water and freeze them.

2. Remove the ice cubes from the tray and place in a bowl.

3. Place a bowl in the freezer compartment for a few days.

4. Taste or smell the ice cubes.

If the taste or odor is present in the ice cubes, then the odors are coming from the

refrigerator or freezer compartment. The odors are present in the air and as they circulate

between the two compartments, the ice cubes absorb the odors. If the bowl of ice cubes has

no odors or bad taste, then the bad taste and odor are coming from the water supply that

feeds the automatic ice maker and/or water dispenser. Once every two or three weeks,

replace the old ice cubes with new ones.

Food molds often grow on baked goods, produce, and leftovers and dairy products. Mold is

caused by microbes that attach to the food surface and causes the food to go bad. Underneath

the food’s surface the mold cells attack the remainder of the food, causing it to rot out.

As food is stored in the refrigerator it loses taste, texture, and nutritional value.

Improper handling or storing of foods can cause food-related illness or even disease. To

clean the mold from the refrigerator, throw away spoiled food, and clean the walls and

shelves in the refrigerator and freezer compartments. Follow the use and care instructions

that came with the refrigerator for proper cleaning instructions.

Step-by-Step Troubleshooting by Symptom Diagnosis

When servicing an appliance, don’t overlook the simple things that might be causing the

problem. Step-by-step troubleshooting by symptom diagnosis is based on diagnosing

malfunctions, with possible causes arranged into categories relating to the operation of the

refrigerator. This section is intended only to serve as a checklist to aid you in diagnosing a

problem. Look at the symptom that best describes the problem you are experiencing with

the refrigerator, and then correct the problem.

The Refrigerator Does Not Operate

Compressor Will Not Run

Compressor Kicks Out on Overload

overheat the compressor. Low voltage will try to run the compressor with the start

winding. A compressor is designed to start and run within a 10 percent tolerance of

the rated voltage.

PART VI

Refrigerator Is Too Cold

(thermostatically controlled dampers only).

temperature may be too cold.

Refrigerator Is Too Warm

heaters if they are coming on when the refrigeration cycle is running.

(thermostatically controlled dampers only).

Refrigerator Is Too Noisy

Sweating on the Outside of the Cabinet

will sweat.

Sweating on the Inside of the Cabinet

necessary.

Incomplete Defrosting of the Evaporator Coil or High Temperature During the Defrost Cycle

Odor in Cabinet

Excessive Frost Buildup on Evaporator Coil in the Freezer Section

PART VI

Freezer Section Run Time Is Too Long

Temperature in Freezer Section Is Higher Than Normal

Refrigerator Runs Excessively or Continuously

properly.

Temperature-Controlled Drawers Are Too Warm

Troubleshooting Sealed-System Problems

If you suspect a sealed-system malfunction, be sure to check all external factors first.

These include:

After eliminating all of these external factors, you will systematically check the sealed

system. This is accomplished by comparing the conditions found in a normally operating

refrigerator/freezer. These conditions are:

One thing to keep in mind is that no single indicator is conclusive proof that a particular

sealed-system problem exists. Rather, it is a combination of findings that must be used to

definitely pinpoint the exact problem.

Refrigerant Leak

The following symptoms may indicate there is a refrigerant leak in the sealed system:

through the coil.

intermittent hissing or gurgling noise.

frost pattern.

Overcharged Refrigerator

If the sealed system is overcharged, the symptoms are:

a higher sound level than normal.

PART VI

pattern. If you remove the back cover, located behind the refrigerator/freezer, you

will possibly see the suction line frosted back to the compressor.

Slight Restriction

The symptoms of a slight restriction in the sealed system are:

Partial Restriction

The symptoms of a partial restriction in the sealed system are:

the coil.

low sound level.

receded.

Complete Restriction

The symptoms of a complete restriction in the sealed system are:

model/serial plate.

frost on it or the frost will be melting.

Moisture Restriction

The symptoms of a moisture restriction in the sealed system are:

model/serial plate.

at all.

frost on the evaporator inlet.

equalization at all.

Low-Capacity Compressor

The symptoms of a low-capacity compressor in the sealed system are:

plate.

frost pattern.

Repair Procedures

Each repair procedure is a complete inspection and repair process for a single refrigerator

component. It contains the information you need to test the components and replace them,

if necessary.

any refrigerator. Any improper installation, preventative maintenance, or repairs will create a

risk of personal injury, as well as property damage. Call the service manager if installation,

preventative maintenance, or the repair procedure is not fully understood.

PART VI

Electronic Control Board and Touchpad

The electronic control board and touchpad are located in the fresh food compartment as

soon as you open the door on some models. On other models the electronic control board

and touchpad are located on the outside of the freezer door. The touchpad allows the

consumer to monitor and control temperatures within the refrigerator and freezer sections.

The electronic control on the freezer door also allows the consumer to dispense water and

ice from the refrigerator’s freezer section. Another great feature that was added by

manufacturers is the ability for technicians to enter into the service mode to run any

function within the refrigerator. If any problem occurs in the refrigerator, an error/fault

code appears and signals the consumer that they have a problem with the refrigerator.

The typical complaints associated with the electronic control board and touchpad are:

To prevent electrostatic discharge (ESD) from damaging expensive electronic components,

follow the steps in Chapter 11.

To handle these problems, perform the following steps:

Turn off the electricity to the appliance and wait for two minutes before turning it

back on. If a fault code appears, look up the code. If the refrigerator will not power

up, locate the technical data sheet behind the panel or cabinet for diagnostics

information. On some models you will need the actual service manual for the

model you are working on to properly diagnose the refrigerator. The service

manual will assist you in properly placing the refrigerator in the service test mode

for testing the refrigerator functions.

the appliance. Is there electricity to the refrigerator? Is the electrical receptacle

polarized and properly grounded? The voltage at the receptacle is between 108

volts and 132 volts during a load on the circuit. Do you have the correct polarity?

(See Chapter 6.)

electricity. This can be done by pulling the plug out of the wall receptacle. Or

disconnect the electricity at the fuse panel or circuit breaker panel. Turn off the

electricity.

the electronic control board and touchpad by removing the screws on the access

panel. Depending on the model you are servicing, the electronic control board and

touchpad can be in the refrigerator or freezer compartment, or the outside of the

freezer door.

diagnostic test mode, check the different functions of the refrigerator. Use the technical

data sheet for the model you are servicing to locate the test points on the wiring

schematic. Check all wiring connections and wiring. Using the technical data sheet, test

the electronic control and display board, input voltages, and output voltages.

screws that secure the PCB to the refrigerator. Disconnect the connectors from the

electronic control board or display board.

procedure, and reassemble. Reinstall all panels or the console panel, and restore the

electricity to the refrigerator. Test the refrigerator operation. Make sure to take the

refrigerator out of the service test mode when the repair is completed.

Door Gasket

The door gasket consists of a vinyl rubber gasket with a magnet. The magnet helps secure

the door closed to keep the cold inside the box and the heat out.

The typical complaints associated with door gasket failure are:

To handle these problems, perform the following steps:

sealing and alignment. Inspect the gaskets for any damage.

appliance. Is the appliance installed properly? Were the doors reinstalled correctly?

electricity. This can be done by pulling the plug from the receptacle. Or disconnect the

electricity at the fuse panel or at the circuit breaker panel. Turn off the electricity.

freezer door. The gaskets are located on the door.

place it between the gasket and the flange of the outer cabinet (Figure 25-4).

Pull on the dollar bill. When pulling on the dollar bill, you should feel some tension

as the bill is gripped. This means that the gasket is making good contact with the

PART VI

refrigerator/freezer flange. Repeat this test in other areas where you suspect problems

with the gasket. If the gasket fails this test, the next step is to replace the gasket. For

the doors to close and seal properly, the refrigerator should tilt backwards 1/4 of an

inch. This is accomplished by raising the front legs or wheels according to the

installation instructions. If you are still unable to get the doors to close properly, check

the doors for sagging or warping (Figure 25-5). Also, check the floor to see if it is level

under the refrigerator/freezer. Check from front to back and from side to side.

To remove the door gasket, pull back on the gasket—this exposes the retaining strip

and screws. Loosen the screws about halfway, but do not remove them (Figure 25-6).

Gently remove the gasket from around the door (Figure 25-7). On some models the

door gasket is held in a retainer track. Just pull on the gasket corners to remove it.

This type of gasket installation uses no screws to secure it to the door.

FIGURE 25-4

The gasket must

make full contact with

the cabinet lange.

for about 15 to 20 minutes. This will make the gasket soft and easier to install.

Starting at either top corner, insert the flange of

the gasket behind the retaining strip and/or door

liner. Proceed all the way around the door. When

the gasket is in place, begin to tighten the screws

slightly all around the door. Now close the door;

the gasket should make contact with the cabinet

flange evenly and all around the door (Figure 25-8).

The door gasket might be adjusted by aligning the

door panel, as shown in Figure 25-9. To align the

door, twist the door in the opposite direction of

the warp. Close the door, and check that the

gasket is sealed against the cabinet. Now that the

door gasket is sealing properly, tighten the screws

completely. If the gasket is distorted, or if it has

wrinkles in it, use a hair dryer to heat the gasket

and mold it to its original form.

Then recheck to be sure the gasket seats

against the flange properly. Next, check the gap

between the door and the cabinet on the hinge

side. Use a penny, which is about 3/4 of an inch in

diameter, to check the gap. Slide the penny from the top hinge to the bottom hinge. The

door might be adjusted by moving the top hinge and by adding or removing shims to the

Retaining

strip

Gasket

to the retaining strip and screws.

gasket so as not to damage the

inner door liner.

Retaining strip

Gasket

door straight when tightening the screws.

PART VI

center and bottom hinges. Be sure that the doors line up evenly with the sides of the cabinet

and evenly with each other. Also, check that when both doors are opened simultaneously

(top-mount refrigerators only), they do not hit against each other. For other models, align

the new door gasket against the door. Starting at the upper corner, push on the gasket until

it seats into the retainer and it is flush to the door.

Thermostat (Cold Control)

The thermostat (cold control) is located in the fresh food compartment (Figure 25-10). The

cold control maintains the temperature in the refrigerator. It turns the compressor and fans

on and off at preset temperature settings.

The typical complaints associated with failure of the thermostat (cold control) are:

To handle these problems, perform the following steps:

control off; then turn it on again and see if the refrigerator/freezer starts.

the appliance. Is the appliance installed properly? Explain to the user how to set the

controls. The voltage at the receptacle is between 108 volts and 132 volts during a

load on the circuit. Do you have the correct polarity? (See Chapter 6.)

the electricity to the refrigerator/freezer. This can be done by pulling the plug from

the receptacle. Or disconnect the electricity at the fuse panel or at the circuit breaker

panel. Turn off the electricity.

Cabinet

Door

Magnetic

gasket

3/4"

FIGURE 25-9

The correct gap

between the door and

cabinet will allow the

door to close and seal

properly. The gap

should also be

checked as the gasket

starts rolling inward

when the door is

closed.

Look for the control dial that has the word “off” printed on it. This is the control that

turns the compressor on and off. Remove the dial (Figure 25-10). Next, remove the two

screws that secure the control (Figure 25-11). Remove the wires from the terminals.

On some models, the capillary tube is inserted in the air duct; on other models, the

capillary tube might be attached to the evaporator coil. At this point, if the capillary

tube is attached to the coil, do not remove the capillary tube yet. Test the control first.

might not cool or it could freeze the food in the fresh food compartment or keep the

temperatures warmer than normal. To test the thermostat, place the ohmmeter

continuity. With the control set in the “off” position, you should not read continuity.

When the control is set to the highest position, you should read continuity. If the

thermostat is good, the problem must be elsewhere.

capillary tube must now be removed. Because there are many different models on

the market today, Figure 25-13 represents only a few types. The capillary tube might

be routed through the control housing (Figure 25-13a). The capillary tube might be

secured to the evaporator by means of a clamp (Figure 25-13b). The capillary tube

might be inserted into a housing that senses how cold the air is (Figure 25-13c).

Whichever way the capillary tube is installed, remove it carefully so as not to

damage the other components.

new thermostat, just reverse the order of

disassembly, and reassemble. Then test

the control. Remember to reinstall the

capillary tube in the same location from

which it was removed. If you do not,

the refrigerator/freezer will not work

properly.

Defrost Timer

The purpose of the defrost timer is to

regulate the frequency of the defrost cycles

and their duration. The defrost timer also

limits the maximum amount of time that

the defrost heater can be energized. There

the thermostat.

Thermostat

control dial

PART VI

are two types of configurations used in a

mechanical timer. They are continuous run

and cumulative run. The difference between

the two is the way that the timer motor is

energized. The continuous run timer will

be energized anytime when the refrigerator

is plugged in, and the cumulative run

timer is energized when the cold control

is calling for cooling and the compressor

is running.

The typical complaints associated with

failure of the defrost timer are:

too warm.

To handle these problems, perform the

following steps:

complaint by asking the customer to

describe what the refrigerator/freezer is

doing or did. On some models you will

need the actual service manual for the

model you are working on to properly

diagnose the refrigerator.

check for external factors not associated

with the appliance. Is the appliance

installed properly? Are the doors aligned

properly? The voltage at the receptacle is

between 108 volts and 132 volts during a

load on the circuit. Do you have the

correct polarity? (See Chapter 6.)

on the refrigerator/freezer, disconnect the

electricity to the appliance. This can be

done by pulling the plug from the

receptacle. Or disconnect the electricity at

the fuse panel or at the circuit breaker

panel. Turn off the electricity.

disconnected before attempting to remove the

thermostat. Note how the capillary tube is routed and if

it is secured to anything. Also note in which direction

the terminal end of the thermostat is pointed when

removing it. If you install the thermostat upside down,

the dial indicators will be incorrect. The thermostat

inside the cabinet could be set on the wrong position.

56789:;<=<

Capillary

line

OHMS

6 8 10 15 20 30 50 100

200

5 4 3 2 1 0

OHMS

DC

AC

DC

AC

54 2 3 1 0

30 50 100 200 500

250

50

10

200

40

8

150

30

6

100

20

4

50

10

2

25

5

10

25

20

4

8

20

15

3

6

15

10

8

10

2

4

10

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OVERLOAD PROTECTED

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DC AC

DC

ALL TERMINALS 10V MAX

􀀂

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1VDC

2.5V

AMP CLAMP

10V

100V

2.5V

50mA

250V

500V

1000V

OFF

TRANSIT

L P ( )

0.5mA

5mA

AMPS

50mA

500mA

OUTPUT

150 VDC

MAX

OHMS ADJ

5A 50mA

250mV

dB

continuity and inspect the capillary tube for damage.

some models, the defrost timer is located on the bottom, behind the toe plate; or it might

be behind the temperature control housing, in the fresh food section (Figure 25-14); or it

might be in the back of the refrigerator, behind the rear leg (Figure 25-15).

Defrost

timer

Mullion heater

switch

Control

knob

Temperature

control Control box

Capillary tube

housing

(c)

Evaporator

Thermostat

routing Clamp

(a) (b)

Capillary line

Temperature

control

(b) The capillary tube is attached to the evaporator plate. Note exactly where the capillary tube is attached.

If you remove it for any reason, you must reattach it in the same position. (c) Capillary tube location within

the housing.

PART VI

from its mounting position. Remove the two mounting screws from the defrost

timer (see Figure 25-15). Next, remove the wire harness plug from the defrost timer

(Figure 25-16).

slot (Figure 25-17), and turn it clockwise until you hear the first “snap.” The defrost

timer is now in the defrost cycle. At this point, you must read the wiring diagram to

determine which numbered terminals are for the defrost circuit. For the purpose of

demonstrating how to check for continuity of the switch contacts, Figure 25-18a

illustrates the internal components of this sample timer. Set the ohmmeter scale on

should measure continuity. Next, rotate the timer cam until you hear the second

“snap.” The meter will show no continuity, indicating that the defrost cycle is over

and that the refrigeration cycle begins.

Temperature

control

Housing

Lamp

socket

Defrost timer and

thermostat located

together in one

housing.

FIGURE 25-15

Remember to always

reconnect the green

ground wire to the

defrost timer and

ground.

Quick

disconnect

plug

Ground

wire

Timer

mounting

screws (2)

Rear leg

Defrost timer

Now place the meter probes on the terminals marked 3 and 4. The ohmmeter will

show continuity, indicating the refrigeration cycle is activated. Turn the timer cam

once again, until you hear the first “snap.” The meter will show no continuity.

At no time should there be continuity between terminals 2 and 4. (If so, the switch

contacts are burned and welded together and the defrost timer must be replaced.)

If the defrost timer passes this portion of the test, you must determine if the timer

mechanism is functioning. Place the ohmmeter probes on the timer motor leads and

read the resistance. The resistance can be between 800 and 4000 ohms, depending

on the type of timer used by the manufacturer. If you are unable to read resistance,

the timer motor is defective.

If the defrost timer passes this portion of the test, rotate the timer cam until you hear

the first “snap.” Advance the timer cam again, counting the number of clicks until you

FIGURE 25-16

Not all defrost timers

have harness plug

connectors. Some are

wired with individual

wires. If you forget

how to reconnect the

wires properly, read

the wiring diagram.

Harness

plug

Defrost

timer

FIGURE 25-17

Always rotate the

timer cam clockwise.

1

2

PART VI

hear the second “snap.” Write down the number of clicks on a piece of paper. Now

rotate the timer cam again until the marks line up (Figure 25-18b), which indicates

the beginning of the defrost cycle, and the “snap” is heard. Advance the timer cam

and count the clicks until there is one click left before the end of the defrost cycle. Take

the timer and reconnect it to the wiring harness (see Figure 25-16). Place the defrost

timer on a nonmetallic surface.

Reconnect the voltage supply to the refrigerator/freezer.

FIGURE 25-19

Check switch contacts

for continuity.

OHMS

6 8 10 15 20 30 50100

200

5 4 3 2 1 0

OHMS

DC

AC

DC

AC

5 4 2 3 1 0

30 50 100 200 500

250

50

10

200

40

8

150

30

6

100

20

4

50

10

2

25

5

10

25

20

4

8

20

15

3

6

15

10

8

10

2

4

10

5

1

2

5

6 4 2 02 4 6

VOLT-OHM MILLIAMMETER

DC AC

DC

ALL TERMINALS 10V MAX

􀀂

L P ( )

1VDC

2.5V

AMP CLAMP

10V

100V

2.5V

50mA

250V

500V

1000V

OFF

TRANSIT

L P ( )

0.5mA

5mA

AMPS

50mA

500mA

OUTPUT

150 VDC

MAX

OHMS AD J

5 A 50mA

250 mV

dB

1 4 32

Motor drive gear Marks

Ground #1

Compressor #4

Common #3

Defrost #2

Switch contacts

Cam

1 4 3 2

(a) (b)

are all welded together. Symptoms in the refrigerator/freezer will be warmer temperatures than normal.

of disassembly, and resemble. Remember to reconnect the ground wire to the

defrost timer.

Adaptive Defrost Control

Conventional defrost systems use electromechanical timers with a fixed defrost cycle.

Adaptive defrost systems use an electronic control to determine when the defrost cycle is

necessary. In order to accomplish the correct time to defrost the evaporator coil, the

adaptive defrost control monitors the following refrigerator operations:

The typical complaints associated with failure of the adaptive defrost control are:

To prevent electrostatic discharge (ESD) from damaging expensive electronic

components, follow the steps in Chapter 11.

To handle these problems, perform the following steps:

Turn off the electricity to the appliance and wait for two minutes before turning it

back on. If a fault code appears, look up the code. If the refrigerator will not power

up, locate the technical data sheet behind the control panel or cabinet for

diagnostics information. On some models you will need the actual service manual

for the model you are working on to properly diagnose the refrigerator. The service

manual will assist you in properly placing the refrigerator in the service test mode

for testing the refrigerator functions.

the appliance. Is there electricity to the refrigerator? Is the electrical receptacle

polarized and properly grounded? The voltage at the receptacle is between 108 volts

and 132 volts during a load on the circuit. Do you have the correct polarity? (See

Chapter 6.)

PART VI

electricity. This can be done by pulling the plug out of the wall receptacle. Or

disconnect the electricity at the fuse panel or circuit breaker panel. Turn off the

electricity.

defrost control by removing the screws on the access panel. Depending on the

model you are servicing, the adaptive defrost control can be in the rear of the

refrigerator (Figure 25-20).

diagnostic test mode, check the different functions of the refrigerator. Use the technical

data sheet for the model you are servicing to locate the test points on the wiring

schematic. Check all wiring connections and wiring. Using the technical data sheet, test

the adaptive defrost control board, input voltages, and output voltages.

FIGURE 25-20

On this model, the

adaptive defrost

control is located on

the back of the

refrigerator. Remove

the screws that

secure the cover to

the back. This will

expose the board for

testing.

screws that secure the PCB to the refrigerator. Disconnect the connectors and wires

from the adaptive defrost control board.

procedure, and reassemble. Reinstall all panels or the console panel, and restore the

electricity to the refrigerator. Test the refrigerator operation. Make sure to take the

refrigerator out of the service test mode when the repair is completed.

Evaporator Fan Motor

The evaporator fan motor provides air circulation over the evaporator coil located in the

freezer compartment of the refrigerator. It also provides air circulation throughout the

refrigerator compartments to remove the heat from within the refrigerator. There are two

types of evaporator motors used in the modern refrigerator. One type is a shaded pole,

single-speed motor that runs on 120 VAC, and the other evaporator motor is a PWM (pulse

width modulation), three-speed motor utilizing a permanent magnet, four-pole, DC motor,

which operates with the electronic control board.

The typical complaints associated with failure of the evaporator fan motor are:

To handle these problems, perform the following steps:

Evaporator cover

FIGURE 25-21

After removing the

evaporator cover in

this type of

refrigerator, remove

the heat shield to gain

access to the

components.

PART VI

the refrigerator/freezer is doing or did. Is the evaporator fan motor running? Is it

noisy? Turn off the electricity to the appliance and wait for two minutes before

turning it back on. If a fault code appears, look up the code. If the refrigerator will

not power up, locate the technical data sheet behind the control panel or cabinet for

diagnostics information. On some models you will need the actual service manual

for the model you are working on to properly diagnose the refrigerator. The service

manual will assist you in properly placing the refrigerator in the service test mode

for testing the refrigerator functions.

the appliance. Is the appliance installed properly? Is there something hitting the fan

blade? Is there electricity to the refrigerator? Is the electrical receptacle polarized and

properly grounded? The voltage at the receptacle is between 108 volts and 132 volts

during a load on the circuit. Do you have the correct polarity? (See Chapter 6.)

the electricity. This can be done by pulling the plug from the receptacle. Or

disconnect the electricity at the fuse panel or at the circuit breaker panel. Turn off

the electricity.

evaporator cover must be removed (Figure 25-21). Remove the screws that secure

the cover in place. On some models, the evaporator fan assembly is located on the

rear wall of the interior freezer compartment.

should be tested for proper resistance, as indicated on the wiring diagram. To test the

evaporator shaded pole, fan motor, remove the wires from the motor terminals.

Next, place the probes of the ohmmeter on the motor terminals (Figure 25-22). Set

replace the motor. If the fan blade does not spin freely, replace the motor. If the fan

motor runs and it is noisy (bad bearings), replace the motor. To test the PWM (pulse

width modulation) motor, you do not use an ohmmeter. You must observe circuit

polarity; otherwise, the motor or electronic control board will short out. Set your

multimeter on DC volts. DC common is not AC common. Using the wiring diagram,

you will verify two voltage potentials: (a) Red wire to white wire—power for

internal electronic control board. (b) Yellow to white—power for the fan motor. Keep

in mind that this type of motor is a DC motor. PWM motors can be run for short

periods of time by using a 9-volt battery. Connect the white wire to the negative (–)

battery terminal only. Next, connect the red and yellow wires to the positive (+)

battery terminal. If the motor runs, disconnect the battery from the motor.

first remove the fan blade. On most models, just pull the blade off the motor shaft.

Be careful not to break the blade. On other models, the fan blade is held on the

motor shaft with screws. Remove the screws. Then remove the screws that secure

the fan assembly to the cabinet (Figure 25-23). On some models, you must remove

the fan shroud (Figure 25-24) by removing the shroud screws.

reverse the order of disassembly, and reassemble. When reinstalling the fan blades

onto the motor shaft, the fan blades should be positioned on the shaft so that onethird

of its depth (approximately 1/4 inch) protrudes through the fan orifice in the

direction of airflow. When reinstalling any shrouds, grilles, ducts, or gaskets, always

position them correctly to ensure the proper airflow through the evaporator and

within both compartments of the refrigerator/freezer. Remember to reconnect the

ground wire to the motor. Reconnect the wires to the motor terminals, and test.

On electronic models, make sure to take the refrigerator out of the service test mode

when the repair is completed.

OHMS

200

5 4 3 2 1 0

OHMS

DC

AC

DC

AC

7 10 15 20

5 4 2 3 1 0

30 50 100 200 500

250

50

10

200

40

8

150

30

6

100

20

4

50

10

2

25

5

10

25

20

4

8

20

15

3

6

15

10

8

10

2

4

10

5

1

2

5

64 2 0 2 4 6

OVERLOAD PROTECTED

VOLT-OHM MILLIAMMETER

DCAC

DC

ALL TERMINALS 10V MAX

􀀂

L P ( )

1VDC

2.5V

AMP CLAMP

10V

100V

2.5V

50mA

250V

500V

1000V

OFF

TRANSIT

L P ( )

0.5mA

5mA

AMPS

50mA

500mA

OUTPUT

150 VDC

MAX

O HMS ADJ

5A 50mA

250mV

dB

Ground wire

FIGURE 25-22

Check the evaporator

fan motor for

resistance. Also check

the motor for

grounded windings.

Rear bracket

Grommet

Fan motor

Front bracket

Fan blade

Evaporator

cover

PART VI

Condenser Fan Motor

The condenser fan motor can be either a 120 VAC single-speed or a DC single-speed fan

fan motor is located near the compressor in the machine compartment in the rear of the

refrigerator on most models. When operating, the condenser fan motor will pull air across

the condenser coil and then exhaust it past the compressor and out through the front of the

refrigerator. The condenser fan will remove the heat from the condenser coil.

The typical complaints associated with failure of the condenser fan motor are:

To handle these problems, perform the following steps:

the refrigerator/freezer is doing. Is the condenser fan motor running? Turn off the

electricity to the appliance and wait for two minutes before turning it back on. If a

fault code appears, look up the code. If the refrigerator will not power up, locate the

technical data sheet behind the control panel or cabinet for diagnostics information.

On some models you will need the actual service manual for the model you are

working on to properly diagnose the refrigerator. The service manual will assist

you in properly placing the refrigerator in the service test mode for testing the

refrigerator functions.

Shroud

screw

Fan mounting

screw

Shroud

screw

Shroud screw

Fan mounting

screw

Shroud screw

the appliance. Is the appliance installed properly? Is there any foreign object

blocking the condenser fan blade? Is there electricity to the refrigerator? Is the

electrical receptacle polarized and properly grounded? The voltage at the receptacle

is between 108 volts and 132 volts during a load on the circuit. Do you have the

correct polarity? (See Chapter 6.)

the electricity. This can be done by pulling the plug from the receptacle. Or

disconnect the electricity at the fuse panel or at the circuit breaker panel. Turn off

the electricity.

away from the wall. Remove the back panel, which is located at the bottom of the

refrigerator/freezer. This will expose the compressor, the condenser fan assembly,

and the condenser coil (Figure 25-25).

for proper resistance, as indicated on the wiring diagram. Check the fan blade for

obstructions. The blade should turn freely. Next, rotate the fan blade and check for

bad bearings. If you hear any unusual noises coming from the motor, or if the fan

blade is sluggish when spinning, replace the motor.

To test the condenser fan motor, remove the wires from the motor terminals. Next,

place the probes of the ohmmeter on the motor terminals (Figure 25-26). Set the

Compressor Compressor terminals

Vertical

bracket

Condenser

fan motor

FIGURE 25-25

Removing the rear

panel will expose the

components that need

to be serviced.

PART VI

the motor. When testing a DC condenser fan

motor, unplug the refrigerator to reset the

electronic control board. At the condenser fan

connector, check for 12 volts DC from the red

to white wire and from the pink and white

wire. If there is 12 volts DC, replace the motor.

You may also have to test the electronic

control board for a short. Use the technical

data sheet to assist you in your final

diagnosis. To test for a shorted DC condenser

fan motor, place your ohmmeter leads

between white and red or white and yellow

wires. If you read less than 1k ohm, replace

the motor.

the condenser fan motor, you must first

remove the fan blades. Unscrew the nut that

secures the blades to the motor. Remove the

blades from the motor. Then remove the

motor assembly by removing the mounting

bracket screws (Figure 25-27).

the new condenser fan motor, just reverse the

order of disassembly, and reassemble.

Remember to reconnect the ground wire to

the motor. Reconnect the wires to the motor

terminals, and test. On electronic models, make sure to take the refrigerator out of

the service test mode when the repair is completed.

Defrost Heater

Most manufacturers also use a single-calrod type, radiant heater, mounted under the evaporator

coil for maximum defrosting of the evaporator coil. Other manufacturers use defrost heaters

that are made with nickel-chromium wire, encased in a glass tube, having both tensile

strength and high resistance to current flow, and are mounted to the evaporator coil.

The typical complaints associated with failure of the defrost heater are:

>?@AB@CBD EF@ G?H?D

Multitester

meter on the ohm scale when testing for

resistance in the condenser fan motor.

To handle these problems, perform the following steps:

the refrigerator/freezer is doing. Is food spoiling? Check the temperature in the

compartments. Check for ice buildup on the evaporator cover. Turn off the electricity

to the appliance and wait for two minutes before turning it back on. If a fault code

appears, look up the code. If the refrigerator will not power up, locate the technical

data sheet behind the control panel or cabinet for diagnostics information. On some

models you will need the actual service manual for the model you are working on to

properly diagnose the refrigerator. The service manual will assist you in properly

placing the refrigerator in the service test mode for testing the refrigerator functions.

Fan blade

Washer

Motor

Nut

Condenser fan blade

Mounting bracket

Key-hole

slots

Mounting

brackets

Dividing

baffle

becoming off balance. On some models, the compressor is located within inches of the motor. Be careful!

The compressor might be hot, and you could burn yourself.

PART VI

with the appliance. Is the appliance installed properly? Is there electricity to the

refrigerator? Is the electrical receptacle polarized and properly grounded?

The voltage at the receptacle is between 108 volts and 132 volts during a load on

the circuit. Do you have the correct polarity? (See Chapter 6.)

electricity. This can be done by pulling the plug from the receptacle. Or disconnect

the electricity at the fuse panel or at the circuit breaker panel. Turn off the electricity.

must be removed (see Figure 25-21). Remove the screws that secure the cover in place.

indicated on the wiring diagram. To test the defrost heater, remove the wires from

the heater terminals. Next, place the probes of the ohmmeter on the heater terminals

reading is indicated, replace the defrost heater.

must first remove the reflector shield (Figure 25-29). Bend the clip up and lift the

shield. Do the same for the other end of the heater. Once the shield is removed, you

can lift the defrost heater from its brackets.

has glass defrost heaters in it that look

black, dark smoky-gray, or burned, the heater

is either defective or soon will be.

be careful not to break the glass. The clip must be

straight so the heater can slide out of the brackets.

Ohmmeter Defrost heater

(under metal shield)

Clip

Defrost

heater element

Reflector shield

reverse the order of disassembly, and reassemble.

Defrost Thermostat

The defrost thermostat is a bimetal switch installed on the evaporator coil, which provides

over-temperature protection during defrost. The defrost heaters will defrost the evaporator

coil within a given time. But, if the evaporator coil is totally defrosted before the time has

expired, the defrost thermostat will open up, shutting off the defrost heater to prevent the

evaporator coil area from overheating.

The typical complaints associated with failure of the defrost thermostat are:

To handle these problems, perform the

following steps:

by asking the customer to describe what the

refrigerator is doing. Is food spoiling?

Check the temperature in all compartments.

Check for ice buildup on the evaporator

cover. Turn off the electricity to the

appliance and wait for two minutes before

turning it back on. If a fault code appears,

look up the code. If the refrigerator will not

power up, locate the technical data sheet

behind the control panel or cabinet for

diagnostics information. On some models

you will need the actual service manual for

the model you are working on to properly

diagnose the refrigerator. The service

manual will assist you in properly placing

the refrigerator in the service test mode for

testing the refrigerator functions.

Defrost

heater

the shield is back in place, bend back the clip on

the bracket. When you reinstall the wires on the

terminals, use one hand to hold the end of the

heater. This will prevent the glass from cracking if

you push down too hard.

PART VI

with the appliance. Is the appliance installed properly? Is there electricity to the

refrigerator? Is the electrical receptacle polarized and properly grounded?

The voltage at the receptacle is between 108 volts and 132 volts during a load on

the circuit. Do you have the correct polarity? (See Chapter 6.)

the electricity. This can be done by pulling the plug from the receptacle. Or

disconnect the electricity at the fuse panel or at the circuit breaker panel. Turn off

the electricity.

cover must be removed (see Figure 25-21). Remove the screws that secure the cover

in place.

evaporator. To test the defrost thermostat, disconnect the wires to isolate

the thermostat from the rest of the defrost circuit. Next, place the probes of the

ohmmeter on the defrost thermostat wire leads (Figure 25-31). Set the meter scale

very cold, indicating the defrost thermostat is good. The defrost thermostat

switch contacts close when the temperature is colder than its temperature rating

(Figure 25-32). If no reading is indicated, replace the defrost thermostat.

At ambient temperature, you will read no continuity, which will indicate the

thermostat might be good.

Multitester

probes

FIGURE 25-31

Test the defrost

thermostat when it is

connected to the

evaporator coil.

remove the hold-down clamp. On some models, the defrost thermostat and clamp

are one assembly. On other models, the defrost thermostat clamps around the

evaporator tubing. As shown in Figure 25-33, remove this type of defrost thermostat

by squeezing in on the clip and lifting the thermostat up.

the order of disassembly, and reassemble. Remember to reconnect the wires to the

thermostat. When reinstalling any shrouds, grilles, ducts, or gaskets, always position

them correctly to ensure the proper airflow through the evaporator and within

both compartments of the refrigerator/

freezer. On models that have the defrost

thermostat attached to the evaporator coil,

you must reinstall the defrost thermostat

in the same location from which it was

removed. On electronic models make sure

to take the refrigerator out of the service test

mode when the repair is completed.

Compressor, Relay,

and Overload Protector

The compressor (reciprocating or rotary

type) is the heart of the vapor compression

system. It is used to circulate the refrigerant

throughout the sealed system. The relay and

overload are attached to the compressor.

The relay starts the compressor, and the

overload protects the compressor. All three

components are located in the machine

compartment in the rear of the refrigerator.

Part number

L - 45

L - 50

L - 55

L - 60

L - 70

L - 80

L - 90

Open

45

50

55

60

70

80

90

Close

25

30

35

40

50

30

35

Rating stamped

on side of thermostat

L - - -

Wire cap

sure you reinstall it in the same position from which you

removed it. Otherwise, the defrost cycle will not function

properly.

PART VI

The relay can be either a current or a PTC (positive temperature coefficient) type device.

The overload is a bimetal switch that is secured to the outer shell of the compressor.

The typical complaints associated with failure of the compressor are:

To handle these problems, perform the following steps:

the refrigerator is doing. Turn off the electricity to the appliance and wait for two

minutes before turning it back on. If a fault code appears, look up the code. If the

refrigerator will not power up, locate the technical data sheet behind the control

panel or cabinet for diagnostics information. On some models you will need the

actual service manual for the model you are working on to properly diagnose the

refrigerator. The service manual will assist you in properly placing the refrigerator

in the service test mode for testing the refrigerator functions.

the appliance. Is the appliance installed properly? Check for a voltage drop during

refrigerator startup. Is there electricity to the refrigerator? Is the electrical receptacle

polarized and properly grounded? The voltage at the receptacle is between 108 volts

and 132 volts during a load on the circuit. Do you have the correct polarity? (See

Chapter 6.)

electricity. This can be done by pulling the plug from the receptacle. Or disconnect

the electricity at the fuse panel or at the circuit breaker panel. Turn off the electricity.

and away from the wall. Remove the back panel, which is located at the bottom of

the refrigerator. This will expose the compressor, the condenser fan assembly, and

the condenser coil (see Figure 25-25). Next, remove the compressor terminal cover

(Figure 25-34) by removing the retaining clip that secures the cover. Remove the

terminal cover.

pulling it off the compressor terminals without twisting it (Figure 25-35a). Remove

the wires from the relay and label them. On the relay body is stamped the word

TOP. Hold the relay so that TOP is in the up position.

Next, place the probes of the ohmmeter on

the relay terminals marked S and M. Set

show no continuity. Then remove the

probe from the terminal marked M, and

place it on the side terminal marked L. The

reading will show no continuity. Now,

move the probe from terminal S, and place

it on the terminal marked M. The reading

will show continuity. With the probes still

attached, turn the relay upside down

(Figure 25-35b), and perform the same

tests. By turning the relay over, the switch

contacts in the relay will close. When you

retest the relay, you should get the

opposite results: You should have

continuity between terminals S and M and

between S and L; however, the meter will

not read continuity between M and L. If

the relay fails this test, replace it. The elimination method is the best way to test a

PTC (positive temperature coefficient) relay. You would first test the run capacitor,

overload, and then run the compressor with a fused test cord. If all of these

components check out okay, replace the relay.

the overload and compressor terminals. Then remove the overload protector from

the compressor by removing the retaining clip that secures the overload protector to

Clip

Terminal

cover

to the relay and overload protector.

Wire coil

S

M

Multitester

probes

Compressor Side terminal (L)

Compressor

relay

(a) (b)

compressor terminals.

PART VI

the compressor (Figure 25-36a). Next, place the probes of the ohmmeter on the

show continuity. If not, replace the overload protector.

protector. This will expose the compressor terminals. The compressor terminals are

marked C, S, and R. C indicates the common winding terminal; S indicates the start

winding terminal; and R indicates the run winding terminal. (Refer to the actual wiring

probes together, and adjust the needle setting to indicate a zero reading. Next, place the

probes of the ohmmeter on the terminals marked S and R (Figure 25-37a). The meter

reading will show continuity. Now place the meter probes on the terminals marked

C and S. The meter reading will show continuity. Finally, place the meter probes on

the terminals marked C and R. The meter reading will show continuity. The total

number of ohms measured between S and R is equal to the sum of C to S plus C to

R. The compressor should be tested for proper resistance, as indicated on the wiring

diagram.

To test the compressor for ground, place one probe on a compressor terminal, and

attach the other probe to the compressor housing or any good ground (Figure 25-37b).

this for the remaining two terminals. The meter reading will show no continuity. If

you get a continuity reading from any of these terminals to ground, the compressor

is grounded. Replace it.

To test compressors with inverter boards, three-phase AC compressors, and DC

compressors, you must consult the service manual or technical data sheet for the

model you are servicing for the correct testing procedures.

Overload protector

Multitester

probe

Overload protector Clip

(a) (b)

S M

C

the order of disassembly and reassemble. Remember to reconnect the wires to the

overload or relay. On electronic models, make sure to take the refrigerator out of

the service test mode when the repair is completed.

Diagnostic Charts

The following refrigerator diagnostic charts will help you to pinpoint the likely causes of

the particular problem associated with these appliances (Figures 25-38 and 25-39).

Refrigerator Electrical Schematics

The wiring diagrams in this chapter are examples only. You must refer to the actual wiring

diagram for the refrigerator you are servicing. Figure 25-40 depicts an actual wiring schematic

for a side-by-side refrigerator, which includes an automatic ice maker and ice and water

dispensers. On models with the rapid electrical diagnosis (R-E-D) feature, a technician can

make a quick and accurate diagnosis of electrical faults without disassembling the

through the multicircuit connector, which is located behind the front grill. Upon separating

the multicircuit connector, the parallel circuits in the wiring harness will be isolated. This

process will permit you to test all of the electrical components and the related wiring within

the main wiring harness. If an R-E-D test adapter is not available, you can still check the

circuits with an ohmmeter.

Terminal pin

C

S

M Compressor

housing

(a) (b)

PART VI

A basic understanding of the symbols used in the schematic diagram is essential (see

Figure 25-40). The numbered terminals, located in the multicircuit connector, are shown on

the schematic diagram. The component circuits on the schematic diagram are indicated by

an arrow and a number. The point of the arrow indicates a male terminal, and the tail of the

arrow indicates a female terminal. The number identifies the terminal location in the

connector (Figure 25-41).

Remember how to read a wiring schematic. Give the following examples a try.

Refrigerator not cooling

Is the refrigerator

plugged in?

Check for voltage

at wall receptacle

Are the controls

set properly?

Is the compressor

running?

Check for proper air

circulation inside and

outside of the cabinet

Check fuse or

circuit breaker

Check doors for

proper alignment

Test light

switch

Fan motor(s)

running properly?

Test compressor Test fan motor(s)

Test compressor

relay and overload

Test fan switch

Does the light

stay on when the

doors are closed?

Is the refrigerator

in the defrost cycle?

Check for food

items blocking

the door open

Replace

defrost timer

Replace light

switch

Align doors

properly

Advance the defrost

timer if refrigerator

was off for over 1 hour

Compressor runs.

Both fans are running.

Inside cabinet temperature

getting colder

Example #1

The customer explains that the food in the freezer is thawing and the food in the refrigerator

is warm. The customer states the compressor runs constantly. You made your observation

and confirmed that the food is thawing and the compressor is operating. You also noticed

frost on the evaporator cover, which indicates a defrost problem. This indicates to you the

possibility of three components malfunctioning: the defrost heaters, the defrost thermostat,

or the defrost timer. Also, there is a possibility of a broken or loose wiring connection. Set

the refrigerator in the defrost mode first. Advance the defrost timer until you hear the first

“snap” sound coming from the timer.

insert one meter probe into the number 5 male connector pin and the other meter probe into

the number 1 male connector pin (see Figure 25-41a). The ohmmeter should show the

combined resistance of the heaters. This resistance is 16 ohms. If the test is okay, continue on

to the defrost thermostat. If not, replace the heaters.

When testing the defrost thermostat, insert one meter probe into the number 1 male

connector pin and the other meter probe into the number 4 male connector pin (see

Figure 25-41b). The meter reading should indicate zero ohms. If not, replace the defrost