effectively complete most installations and repairs. This chapter will cover the basics

of each tool. A working knowledge of these tools is a must for the installation and

repair of appliances and air conditioners. Always follow safety precautions and

manufacturer’s recommendations and warnings when handling tools.

Before starting on any type of repairs, take the time to put together a toolkit with

a selection of good quality hand tools. A partial list of common hand tools includes:

5/16 inch. Handle sizes may vary with the blade dimension. Phillips-tip sizes also

vary; the two most common are #1 and #2.

5/16, 11/32, 3/8, and 1/2 inch.

a 4-inch size will take up to a 1/2-inch nut. A 16-inch handle will take up to a

17/8-inch nut.

Safety Precautions

Safety starts with accident prevention. Listed in this chapter are some tips to help the

technician when using hand and power tools.

Individual Safety Precautions

Injuries abound when using tools. To be protected from injuries when using hand tools and

power tools, do the following:

Safety Precautions When Handling Tools

Regardless of which tool is being used, these same rules of care and safety apply:

working end of the tool.

wires are showing. Also, use a heavy-gauge wire extension cord to ensure adequate

voltage for the tool being used.

For example, with a worn-out screwdriver, there is a greater possibility for slips,

which could make medical attention necessary.

it first, and then correct the tool’s problem.

components.

Screwdrivers

A screwdriver is a hand tool used either to attach or remove screws. The two most common

types are the flat-blade and Phillips. The flat-blade screwdriver is used on screws that have a

slot in the screw head (Figures 3-1 and Figure 3-3). The flat-blade screwdriver is available in

PART I

many sizes and shapes. Always use the largest blade size that fits snugly into the slot on the

screw head so that it will not slip off the screw. The screwdriver should never be used as a

pry bar or a chisel; it was not designed for that purpose.

A Phillips screwdriver is used to attach or remove screws that have two slots crossing at

right angles in the center of the screw head (Figures 3-2 and Figure 3-3).

When using a Phillips screwdriver, exert more pressure downward in order to keep the

tool in the slots. Always use the largest Phillips size that fits snugly into the slots, just as

with the flat-blade screwdriver.

Never use worn-out screwdrivers when working on appliances. A worn screwdriver may

damage the head of the screw. It can also damage the product on which you are working.

Nut Drivers

Many manufacturers use metal screws with a hexagonal head. A nut driver is a hand tool

similar to a screwdriver, except that the working end of the driver is hexagonal-shaped and

fits over a hexagonal nut or a hexagonal bolt head. Each size nut requires a different sized

driver

Wrenches

Wrenches are the most frequently used tool. There are many different types and sizes of

wrenches. Their purpose is to hold and turn nuts, bolts, cap screws, plugs, and various

threaded parts. Wrenches are generally available in five different types (Figure 3-5):

PART I

Socket wrenches are used to slip over bolt heads, as opposed to other wrenches listed,

which are used at right angles to the nut or bolt. This arrangement allows more leverage to

be applied to loosen or tighten the nut or bolt (Figure 3-6). Select the size and type of socket

to fit the nut with the proper drive size for the load. See Table 3-1 for the proper drive size

loading recommendations.

Always choose the correct wrench for the job. Box wrenches should be used for heavyduty

jobs and in certain close-quarter situations. Open-ended wrenches are useful for

wrench, box, open-end, adjustable, and Allen types.

Hex Size 1/4" Drive 3/8" Drive 1/2" Drive 3/4" Drive 1" Drive

1/8" to 7/32" USE DO NOT USE DO NOT USE DO NOT USE DO NOT USE

1/4" to 11/32" USE USE DO NOT USE DO NOT USE DO NOT USE

3/8" to 9/16" USE USE USE DO NOT USE DO NOT USE

19/32" to 11/16" DO NOT USE USE USE DO NOT USE DO NOT USE

3/4" to 1" DO NOT USE DO NOT USE USE USE DO NOT USE

1 1/16" to 1 1/4" DO NOT USE DO NOT USE USE USE USE

1 1/2" DO NOT USE DO NOT USE DO NOT USE USE USE

1 9/16" to 3 1/2" DO NOT USE DO NOT USE DO NOT USE DO NOT USE USE

PART I

medium-duty work or situations where it is impossible to fit a socket or box wrench on a

nut, bolt, or fitting from the top. Adjustable wrenches help with light-duty jobs, work well

with odd-sized nuts and bolts, and are useful where a regular open-end wrench could be

used. It is adjustable to fit any size object within its maximum opening. Allen wrenches are

used for adjusting and removing fan blades or other components that are held in place by

Allen set screws. The Allen wrench has a six-pointed flat face on either end.

Hammers

A hammer is a hitting tool. There are many sizes and styles of hammers available (Figure 3-7).

The most common type used in appliance repairs is the claw hammer. The claw hammer

can also be used for prying objects.

Prying Tools

Prying tools are available in many sizes and shapes. The most common are the crowbar,

ripping bar, and the claw hammer. The claw hammer is basically used for light-duty work:

removing nails and prying small objects. The ripping bar is used for medium-grade work,

and the crowbar is used for heavier work.

Pliers

Pliers are one of the most frequently used tools. A pliers is a tool for holding or cutting,

depending on the type. Generally, they are not made to tighten or unscrew heavy nuts and

bolts. They are available in many sizes and shapes (Figure 3-8). Choose a pliers that fills a

particular need, being careful that it is the proper pliers for the job. Some of the most

common types of pliers include:

two different positions. Do not use them on nuts, bolts, or fittings. They can easily slip and

injure both the technician and the device.

(Figure 3-8i). They would be preferred over slip-joint pliers when working on a larger

object. The jaws of slip-joint adjustable pliers can be moved into many different positions.

hand vise, and pliers. The lever holds the jaws in one position, allowing the vise to hold up

to one ton of pressure.

Other uses include in confined areas, to form

wire loops, and to grip tiny pieces firmly. (The long nose is particularly useful for this latter

task.) They are also available with side cutters.

Cutting Tools

Many different types of tools are used for cutting. The key is to know which tool to use in

each situation. Chisels are used for cutting metal and wood. They are made of high-carbon

steel, which makes them hard enough to carve through metal (Figure 3-9). These should be

used when removing rusted bolts and nuts.

Hacksaws are used for cutting metal (Figure 3-10). The hacksaw consists of a handle,

frame, and a blade. The frame is adjustable, so it can accept any length of blade. The blades

are available with different numbers of teeth per inch.

A file is also a cutting tool. It is used to remove excess material from objects. Files come

in a variety of sizes and shapes (Figure 3-11).

Drill bits are also cutting tools. They are designed for cutting holes in metal, wood, and

concrete

Tang

Heel

Face Tip

Edge

Length

Round

Slim

Bastard tapered

Half

round

Cross section

Coarse Bastard Second-cut Smooth

Single-cut

Double-cut

A general-purpose

twist drill set will

handle most of the

technician’s needs.

The wood bit and

masonry drill bit are

used in installation

work.

PART I

Power Tools

Power tools do the same job as hand tools. However, they do the job faster. The most

common power tools can be either electric or battery-powered (Figure 3-13).

When using power tools, there are some safety precautions that must be followed to

prevent accidental injury. Always read the use and care manual that comes with each power tool.

Specialty Tools

These tools are specifically designed for a particular use and are used for in-depth servicing

of the appliance. For example, special tools are used for the installation and removal of

special screws and nuts (Figure 3-14); they are required to remove the bearings in washing

machines; and they are also used for adjusting switch contacts. Figure 3-15 illustrates some

of the many types of specialty tools. Other specialty tools and their uses will be discussed in

later chapters of this book.

Test Meters

Test instruments are important tools used in assisting with the diagnosis of the various

problems that arise with appliances. Varieties of test meters (Figure 3-16) include the

following:

voltage of the appliance or air conditioner. This type of meter moves a needle along

a scale. It is also the most important test meter to have in the tool box.

This type of meter is similar in operation to the analog meter.

current of the circuit without interrupting the electrical current.

appliance.

of the appliance.