Chapter 19 Installation and Troubleshooting of Domestic Refrigerators and Freezers
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If the lights turn on and off as expected, the refrig-
erator is being supplied with power, and the problem
is likely in the motor control circuits or the motor
itself. The troubleshooting process should begin with a
visual inspection to check for obvious problems. After
the visual inspection, the external electrical circuits
should be checked for problems. Finally, the system
should be checked for mechanical trouble that prevents
its startup. The troubleshooting process described in
the sections that follow can be applied to a refrigerator
that will not start or one that is performing poorly.
Pro Tip
Restarting a Capillary Tube System
If a refrigerator-freezer equipped with capillary tube
metering device is stopped and then started immedi-di-mmei
ately, it may fail to operate. This is not necessarily a mal-
function. The motor in this type of refrigerator provides
insuffi cient starting torque to overcome high head pres--
sure. Disconnect the refrigerator for a few minutes to
allow the high-side and low-side pressures to
Then, start the system.
19.2.2 Diagnosing Poor Performance
The first step in diagnosing a faulty system is to
visually inspect the system, looking for any obvious
problems. A very helpful device for inspecting a refrig-
erator is an inspection mirror, a small adjustable mirror
mounted on a long extension. A variety of inspection
mirrors is shown in Figure 19-4. Most inspection mir-
rors have a telescoping handle. The mirror pivots and
can be used to check such things as fan alignment,
motor condition, cleanliness of the condenser, and the
condition of the evaporator.
Caution
Inspection Mirrors
When inserting an inspection mirror into a recessed
or obstructed area, be aware that the area may contain
moving parts that are hidden from view. Always avoid
touching moving parts with an inspection mirror.
If a problem is detected during the visual inspec-
tion, determine whether that problem could result in
the symptoms you are investigating. Also, determine
whether the problem you detected during the inspec-
tion could actually be a symptom of an even larger
problem.
After the visual inspection, the next step in diag-
nosing the system is to determine the possible causes
of the symptoms. Troubleshooting charts are very
useful for determining possible causes. Figure 19-5
is a troubleshooting chart listing common troubles,
Restartin g a C apillary Tube S ystem
I f a refrigerator-freezer equipped with capillary tube
metering device i s stoppe d an d th en starte d
atel y, it ma y fail to operate. This is not necessaril y a mal-
f unction. The motor in this type o f refrigerator provides
insu ffi cient starting torque to overcome high head pres
sure. Disconnect the refrigerator f or a f ew minutes to
all ow t h e high-side an d low-side pressures to balance.balance.
Then, start the system.
Inspection Mirrors
When inserting an inspectio n mirror into a recessed
or obstructed area, b e aware that t h e area may conta in
moving parts that are hidden f rom view. Always avoid
touchin g movin g parts with an inspection mirror .
symptoms, their causes, and remedies. This chart
should be considered a general guide only. It does not
apply to all units.
Next, repair or correct the problem. If the prob-
lem could have been a possible cause of the initial
symptoms, retest the system to determine whether the
service corrected the problem. If the service you per-
formed did not correct the symptoms, continue diag-
nosing the system.
A methodical approach is needed to find the cause
of poor operation. Always remember, cooling occurs
only when the evaporator pressure is low enough
and liquid refrigerant is present in the evaporator. For
example, if an evaporator has the correct low pres-
sure but is warm, it indicates there is no liquid in the
evaporator. In another example, a drier is frosting over.
There is liquid refrigerant and also a low pressure in
the drier. The drier is installed in the liquid line and
should have high pressure. The fact that the drier is
under low pressure indicates that the drier is partially
clogged.
Figure 19-6 is a chart listing problems, possible
causes, and solutions for troubleshooting ice makers.
Whether you are troubleshooting the refrigeration
system or an auxiliary system, like an ice maker, the
Ritchie Engineering – YELLOW JACKET Products Division
Figure 19-4. An inspection mirror is often needed to see into
hard-to-reach places.