Chapter 19 Installation and Troubleshooting of Domestic Refrigerators and Freezers
477
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
Summary
✲ To check a refrigerator-freezer for proper
installation, begin by inspecting the unit for
damage resulting from shipping or improper
handling. Ensure that the unit is level and has
adequate ventilation.
✲ Ice makers should be attached to a cold-water
supply line and the water supply tubing should
be long enough to allow the refrigerator to be
moved for cleaning and servicing.
✲ The refrigerator should be on a separate
electrical circuit and properly grounded.
✲ If a refrigerator fails to start, check the supplied
power and then check for electrical problems.
Finally, check for mechanical problems.
✲ The troubleshooting process should begin with
a visual inspection of the system. The next
step after performing a visual inspection is
determining possible causes of the symptoms.
✲ Troubleshooting charts are useful tools for
determining possible causes of common
symptoms. Some common symptoms include
ice on the evaporator, moisture in the cabinet
insulation, unusual noises, unusual cycling
times, and failure to cool.
✲ Eliminate possible external causes for
symptoms before assuming the problem is in
an internal component. Use proper electrical
troubleshooting techniques to make sure there
are no problems with the power-in connections,
thermostats, overload protection, relays, or
capacitors.
✲ A sweating or frosted suction line indicates
that liquid refrigerant is getting into the suction
line. Excessive frosting on the capillary tube
or fi lter-drier and a warm evaporator indicate
that not enough refrigerant is reaching the
evaporator.
✲ Service valves are usually not built into
hermetic systems. However, valve adapters or
piercing valves can be installed in the system
to provide a technician with a means to connect
gauges and service equipment to the system.
✲ Excessively low low-side pressures can be
caused by a restriction in the system or a lack
of refrigerant.
✲ Ice formation in the system can cause
restriction and is an indication of excess
moisture in the refrigerant. To correct the
problem, install a new fi lter-drier to remove
the excess moisture, and then thaw the ice
blockage.
✲ Wax buildup can clog a metering device. If
the shortage of refrigerant in the evaporator is
found to be caused by wax buildup instead of
ice, replace the metering device and fi lter-drier
and replace the refrigerant oil with a high-
quality low-wax oil.
✲ Once you have diagnosed the system based
on visual inspection and analysis of system
performance, perform pinpoint tests to make
sure the suspected component is faulty before
replacing it. Internal system components that
typically cause problems are compressors,
fi lter-driers, metering devices, hot-gas defrost
bypass valves, and electric defrost resistance
heaters.
Review Questions
Answer the following questions using the information in
this chapter.
1. Which of the following statements regarding
shipping bolts is not true?
A. If the compressor is spring mounted, the
shipping bolts are usually removed after the
unit is installed.
B. If the compressor is mounted on synthetic
grommets, the shipping bolts must be
tightened after the unit is installed.
C. The purpose of shipping bolts is to secure
the compressor during shipping.
D. All of the above.
2. Refrigerators should be installed only in rooms
that are _____ or larger.
A. 50 ft2
B. 75 ft2
C. 100 ft2
D. 200 ft2
3. Why should there be several large loops in
the tubing connecting the water line to a
refrigerator’s water line fi tting?
A. To prevent condensation from forming on
the water line.
B. To ensure an adequate pressure drop in the
water supply.
C. To allow the refrigerator to be moved
without disconnecting the water connection.
D. None of the above.