GMC 1976 ZEO 6083 Maintenance Manual page 732

24D- 2 REFRIGERATOR
COMPONENT TESTING
COMPRESSOR VOLTAGE
NOTE : A standard A.C . voltmeter will read a
high A.C . compressor voltage on D.C . operat
The voltage is checked at the compressor termi-
ion. The reason being the inverter does not pro-
nals with an A.C . voltmeter (figure 1) .
duce a true sine wave on D .C . operation. The
Problem Possible Cause Correction
Insufficient cooling, 1 . Improper thermostat 1 . Turn thermostat to higher set-
compressor runs. setting. ting . A setting of "3" should be
adequate at ambient temperatures of
70° - 90°. When storing frozen
food in freezing compartment a
setting of "5" is recommended
for the above temperature
conditions .
" 2. Overpacking of cabinet. 2. Space must be left in between
food to allow for proper convective
heat transfer .
3. Insufficient heat radia- 3a. At ambient temperatures above
tion at condenser. 110°F. the condenser will not be
able to radiate enough heat to main-
tain sufficient cooling, even with
a setting of "5".
b . Dust may have collected
on condenser restricting air flow
and must be removed.
4 . Excess frost build up 4. A frost build up of over one
in freezer compartment. quarter inch should be avoided.
Defrost refrigerator .
5. Freon overcharge or 5. Can be determined by testing
undercharge. compressor amperage . In either
case the entire cooling system
must be replaced .
6. Insufficient voltage 6. Check A.C . and D.C . voltage
source . supply .
7. System "Freeze-up" or 7. Shut-off system and let it cool
clogging . Clogging is down, start-up system let it run for
indicated by a warm evap- 5 minutes, shut-off system for 5
orator plate, a condenser minutes . Restart system . If system
at room temperature, and does not function repeat cycling.
a low amp draw by the If this does not relieve the clog
compressor . replace entire system .
Refrigerator too cold, 1 . Thermostat "sticking" . 1 . Replace thermostat
compressor runs con-
stantly.
2. Thermostat sensing bulb 2. Tighten mounting screws to make
loose on evaporator plate sure bulb has good contact with "
mounting . evaporator plate.