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CRR-20 & CRR-40, September 1999
Diagnosis
Refrigeration Diagnosis
8-5
Condition
Possible Cause
Remedy
Unit operating in a vacuum
Shortage of refrigerant
Repair leak and recharge
(unit not cooling)
Compressor motor contacts frozen
Clean points or replace contactor
NOTE: When the unit is in
Modulation Cool or the
Compressor inefficient
Check valves and pistons
return air temperature is
below -18 C (0 F), the
Defective liquid line solenoid valve
Repair or replace liquid line solenoid valve
suction pressure will be
less than 0 kPa, 0 bar,
Partial obstruction in low side or
Locate obstruction and repair
0 psig during normal
dehydrator
operation
Iced or plugged evaporator coil
Defrost or clean evaporator coil
Expansion valve partially closed by
Clean or replace expansion valve
ice, dirt or wax
Expansion valve power element lost
Replace expansion valve
its charge
Defective container insulation
Correct or replace container insulation
Poor fitting container doors
Repair or replace doors
Partial obstruction in high side
Locate obstruction and repair
Service gauge out of calibration
Replace service gauge
Evaporator pressure regulator (KVQ)
Repair or replace valve
valve stuck closed or defective
Controller out of calibration or
Recalibrate or replace controller
defective
(see Diagnosis Manual for Thermoguard
µ
P-D Microprocessor Controller, TK 41230)
Expansion valve feeler bulb
Correct feeler bulb installation
improperly mounted, poorly insulated
or making poor contact
Refrigeration Diagnosis
Содержание CRR-20
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