8-4
Mechanical Diagnosis
CSR-20 & CSR-40, September 1999
Condition
Possible Cause
Remedy
Condenser fan motor does
Unit in Null, Heat or Defrost
Check indicator lights. If unit is in
not operate
Null, Heat or Defrost, unit operation is
normal (no remedy required)
Unit in Cool or Modulation
Check indicator lights and condenser pres-
sure in View menu of
µ
P-D controller. If
condenser coil temperature is below 35 C
(95 F) and the compressor temperature is
below 50 C (122 F), unit operation is normal
(no remedy required)
Unit on water-cooled condensing
If condenser-receiver tank has water
operation or water pressure
pressure, unit operation is normal.
switch open (option)
Otherwise check water pressure
switch circuit to controller. Correct
defective switch or wiring
Loose line connection
Tighten connections
Open motor internal thermal
Check for seized bearings or defective
overload protector
thermal overload protector. Repair or
replace as necessary
Defective motor
Replace motor
Defective high speed condenser fan
Replace defective contactor
contactor
No high speed condenser fan output
Diagnose and replace output module or
signal from controller
controller. Disconnect water supply to unit
and check water pressure switch (options)
before replacing controller
