62-61753-21
10.4.9 Control System Malfunction
Microprocessor controller malfunction
10.4.10 No Evaporator Air Flow Or Restricted Air Flow
No or partial evaporator
air flow
Check return air bulkhead and air chute. Ensure return air
is not restricted and chute is in good condition
Clean, repair or
replace.
Check coil for even air flow with no "dead" spots. Clean.
Frost on coil. To check defrost, run unit in cooling and
place in manual defrost.
Defrost air switch (DAS) defective or out of calibration
Evaporator blower loose or defective
Evaporator blower rotating backwards
10.4.11 Electronic Expansion Valve Malfunction
Incorrect software and/or controller Configuration
Excessive frost on evaporator coil. Manually defrost.
Suction service valve partially closed
Filter drier partially plugged
No evaporator air flow or restricted air flow
Evaporator fans rotating backwards
Loose or insufficiently clamped suction temperature sen-
sor
Failed suction pressure transducer
Electronic expansion valve malfunction
High suction pressure with low
superheat
improperly seated power head
Ensure power
head is locked in
place
Failed suction pressure transducer
Foreign material in valve
Electronic expansion valve malfunction
Liquid slugging in compressor
Failed suction pressure transducer
Electronic expansion valve malfunction