Craftsman 921.152150 Owner's Manual

Owner’s Manual

®

AIR COMPRESSOR
4-gallon
¾ HP
Oil-Free, Belt Drive
Universal Motor and Pump

Model No. 921.152150

CAUTION:
Before using this product,
read this manual and follow
all its Safety Rules and
Operating Instructions.

Sears, Roebuck and Co., Hoffman Estates, IL 60179 U.S.A.

www.sears.com

03/31/2008
Part No. E152150

• Safety Instructions

• Installation & Operation

• Maintenance & Storage

• Troubleshooting Guide

• Parts List

• Español, p. 10

Table of Contents

Page

Warranty..............................................................

Safety Symbols .......................................................... 1

Important Safety Instructions & Guidelines ..................................... 1

Specifications ............................................................ 2

Glossary ................................................................ 2

Duty Cycle .............................................................. 2

Parts & Features ......................................................... 3

Installation & Assembly .................................................... 4

Operating Procedures ..................................................... 5

See Below

Maintenance............................................................. 6

Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Troubleshooting Guide ..................................................... 7

Exploded View ........................................................... 8

Parts List ............................................................... 9

Español . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

ONE YEAR FULL WARRANTY ON CRAFTSMAN AIR COMPRESSOR

If this Craftsman Air Compressor fails due to manufacturer’s defects in material or workmanship
within one year of the date of purchase, RETURN IT TO THE NEAREST SEARS STORE OR
SERVICE CENTER IN THE UNITED STATES and it will be replaced or repaired (at our option),
free of charge.
If this Air Compressor is used for commercial or rental purposes, this warranty applies for only 90
days from the date of purchase. This warranty gives you specific legal rights and you may also
have other rights which vary from state to state.

Sears, Roebuck and Co., Hoffman Estates, IL 60179

Safety Symbols

The information listed below should be read and understood by the operator. This information is given to protect the
user while operating and storing the air compressor. We utilize the symbols below to allow the reader to recognize important
information about their safety.

DANGER

Indicates an imminently hazardous situation which, if not
avoided, will result in death or serious injury.

WARNING

Indicates a potentially hazardous situation which, if not
avoided, could result in death or serious injury

Indicates a potentially hazardous situation which, if not
avoided, may result in minor or moderate injury.

When used without the safety alert symbol indicates a
potentially hazardous situation which, if not avoided, may
result in property damage.

CAUTION

CAUTION

Important Safety Instructions and Guidelines

• Save all instructions

WARNING

Improper operation or maintenance of this product could result in serious injury and/or property damage. Read and
understand all of the warnings and safety instructions provided before using this equipment.

The air compressor should be operated on a dedicated 15 amp circuit. If the circuit does
not have 15 free amps available, a larger circuit must be used. Always use more air

CAUTION

hose before utilizing extension cords. All extension cords used must be 12 gauge with a
maximum length of 25 ft. The circuit fuse type must be a time delay. Low voltage could
cause damage to the motor.

WARNING: This product contains one or more chemicals known to the State of
California to cause cancer and birth defects or other reproductive harm.
Wash hands after handling.

Risk of Moving Parts

Risk of Burns

Risk of Falling

Risk from Flying Objects

If the air compressor is in operation, all guards and covers should be attached or
installed correctly. If any guard or cover has been damaged, do not operate the
equipment until the proper personnel has correctly repaired the equipment. The power
cord should be free of any moving parts, twisting and/or crimping while in use and while
in storage.

There are surfaces on your air compressor that while in operation and thereafter can
cause serious burns if touched. The equipment should be allowed time to cool before
any maintenance is attempted. Items such as the compressor pump and the outlet tube
are normally hot during and after operation.

Operation of the air compressor should always be in a position that is stable. Never use
the air compressor on a rooftop or elevated position that could allow the unit to fall or
be tipped over. Use additional air hose for elevated jobs.

Always wear ANSI Z87.1 approved safety glasses with side shields when the air
compressor is in use. Turn off the air compressor and drain the air tank before
performing any type of maintenance or disassembly of the hoses or fittings. Never point
any nozzle or sprayer toward any part of the body or at other people or animals.

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Important Safety Instructions & Guidelines

Risk of Breathing

Risk of

Electrical Shock

Risk of

Explosion or Fire

Risk of Bursting

Avoid using the air compressor in confined areas. Always have adequate space
(12 inches) on all sides of the air compressor. Also keep children, pets, and others out of
the area of operation. This air compressor does not provide breathable air for anyone or
any auxiliary breathing device. Spraying material will always need to be in another area
away from the air compressor to not allow intake air to damage the air compressor filter.

Never utilize the air compressor in the rain or wet conditions. Any electrical issues or
repairs should be performed by authorized personnel such as an electrician and should
comply with all national and local electrical codes. The air compressor should also have
the proper three prong grounding plug, correct voltage, and adequate fuse protection.

Never operate the compressor near combustible materials, gasoline or solvent vapors.
If spraying flammable materials, locate the air compressor at least 20 feet away from the
spray area. Never operate the air compressor indoors or in a confined area.

Always drain the air compressor tank daily or after each use. If the tank develops a leak,
then replace the air compressor. Never use the air compressor after a leak has been
found or try to make any modifications to the tank. Never modify the air compressor’s
factory settings which control the tank pressure or any other function.

Specifications

Pump ...........................Oil-Free Belt Drive

Motor ............................¾ HP (Universal)

Bore ...................................... 1.97˝

Stroke ..................................... 0.98˝

Voltage Single Phase ......................120 VAC

Minimum Circuit Requirement ...............8.0 Amps

Air Tank Capacity .........................4 Gallons

Cut-in Pressure ............................95 PSI

Cut-out Pressure ..........................125 PSI

SCFM @ 90 PSI...............................1.7

Glossary

CFM: Cubic feet per minute.
SCFM: Standard cubic feet per minute; a unit of measure

for air delivery.
PSIG: Pounds per square inch gauge; a unit of measure
for pressure.

ASME: American Society of Mechanical Engineers.
California Code: Unit may comply with California Code

462 (l) (2)/ (M) (2).

Cut-In Pressure: The air compressor will automatically
start to refill the tank when the pressure drops
below the prescribed minimum.
Cut-Out Pressure: The point at which the motor stops
when the tank has reached maximum air
pressure.
Code Certification: Products that bear one or more of
the following marks: UL, ULc, ETL, CSA, have
been evaluated by OSHA-certified independent
safety laboratories and meet the applicable
Underwriters Laboratories Standards for Safety.

Duty Cycle

This is a 50% duty cycle air compressor. Do not run the air compressor more than 30 minutes of one hour. Doing so
could damage the air compressor.

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Parts & Features

See figures below for reference.

Regulator Gauge

Indicates the outgoing air pressure to the tool and is
controlled by the regulator.

Tank Pressure Gauge

Indicates the reserve air pressure in the tank.

Quick Connect

Offers a quick release feature for attaching and
removing the air hose.

ON/OFF Switch

Tank Safety Valve

Used to allow excess tank pressure to escape into
the atmosphere. This valve should only open when
the tank pressure is above the maximum rated
pressure.

Regulator

The air pressure coming from the air tank is controlled
by the regulator. To increase the pressure turn the
knob clockwise and to decrease the pressure turn the
knob counterclockwise.

Tank Drain Valve

Used to drain condensation from the air tank.
Located at bottom of tank.

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Installation & Assembly

WARNING WARNING

Improper installation of the grounding plug will result in a
The air compressor should be turned off, unplugged from
the power source, the air bled from the tank and the unit
allowed time to cool before any maintenance is performed.
Personal injuries could occur from moving parts, electrical
sources, compressed air or hot surfaces. The quick connect
assembly must be attached before use. Failure to assemble
correctly could result in leaks and possible injury. If unsure
of assembly instructions or you experience difficulty in the
assembly please call your local service department for
further information.

Getting Started - Location of the Air Compressor

The air compressor should always be located in a clean,
dry and well ventilated environment. The unit should have
at minimum, 12 inches of space on each side. The air filter
intake should be free of any debris or obstructions.
Check the air filter on a daily basis to make sure it is clean
and in working order.

risk of electric shock. If repair or replacement of the cord

or plug is necessary, do not connect the grounding wire to

either flat blade terminal. The wire with insulation having an

outer surface that is green with or without yellow stripes is

the grounding wire. Check with a qualified electrician or

serviceman if the grounding instructions are not completely

understood, or if in doubt as to whether the product is

properly grounded. Do not modify the plug provided.

If it will not fit the outlet, have the proper outlet installed

by a qualified electrician.

This product is for use on a circuit having a nominal rating

of 120 volts and is factory-equipped with a specific electric

cord and plug to permit connection to a proper electric

circuit. Make sure the product is connected to an outlet

having the same configuration as the plug. An adapter

should not be used with this product. If the product must

be reconnected for use on a different type of electric circuit,

qualified service personnel should make the reconnection.

Grounding Instructions

This product should be grounded. In the event of an electrical
short circuit, grounding reduces the risk of electric shock by
providing an escape wire for the electric current.
This product is equipped with a cord having a grounding
wire with an appropriate grounding plug. (See the figure at
top right corner.) The plug must be plugged into an outlet
that is properly installed and grounded in accordance with
all local codes and ordinances. Check with a qualified
electrician or service personnel if these instructions are not
completely understood or if in doubt as to whether the tool
is properly grounded.

Extension Cords

Use only a 3-wire extension cord that has a 3-blade

grounding plug and a 3-slot receptacle that will accept the

plug on the product. Make sure your extension cord is in

good condition. When using an extension cord, be sure to

use one heavy enough to carry the current your product will

draw. Cords must not exceed 25 feet and No. 12 AWG size

must be used. An undersized cord will cause a drop in line

voltage resulting in loss of power and overheating.

Break In Procedures

No break in procedure is required by the user.

This product is factory tested to ensure proper operation and

performance.

Plug

Grounded

Outlet

Grounding Pin

4

Operating Procedures

Daily Start-Up Procedures

1. Set the Auto-On/Off lever to the Off position.

2. I

nspect the air compressor, air hose, and any
accessories/tools being used for damage or obstruction.
If any of these mentioned items are in need of repair/
replacement, contact your local authorized dealer before
use.

3. Close the drain valve.

4. Connect the air hose to the quick connect socket on
the regulator assembly by inserting the quick connect
plug on the air hose into the quick connect socket. The
quick connect socket collar will snap forward and lock
the plug into place providing an air tight seal between
the socket and plug. To release the air hose push the
collar back on the quick connect socket.

5. Plug the power cord into the proper receptacle.

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6. Turn the Auto-On/Off lever to the On-Auto position and
the compressor will start and build air pressure in the
tank to cut-out pressure and then shut off automatically.

7. Adjust the regulator to a PSI setting that is needed for
your application and be sure it is within the safety
standards required to perform the task. If using a
pneumatic tool, the manufacturer should have
recommendations in the manual for that particular
tool on operating PSI settings.

8. The air compressor is now ready for use. The following
inflation and cleaning accessories packaged with this
unit should only be operated at maximum pressure
of 90PSI: blow gun, rubber-tapered nozzle, inflation
needles, adapter, and blow gun adapter.

4

1

5

Daily Shut-Down Procedures

1. Set the On/Off lever to the Off position.

2. Unplug the power cord from the receptacle.

3. Set the outlet pressure to zero on the regulator.

4. Remove any air tools or accessories.

5. Open the drain valve allowing air to bleed from the
tank. After all of the air has bled from the tank, close
the drain valve to prevent debris buildup in the valve.

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3

CAUTION

When draining the tank, always use ear and eye protection.
Drain the tank in a suitable location; condensation will be
present in most cases of draining.

WARNING

Water that remains in the tank during storage will corrode
and weaken the air tank which could cause the tank to
rupture. To avoid serious injury, be sure to drain the tank
after each use or daily.

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