Ingersoll-Rand Thermo King CRR DF MPC2000, Руководство по обслуживанию

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Mechanical Diagnosis
142
Compressor contactor
burned out Low line voltage Increase line voltage to at least 90% of
compressor motor rating
Excessive line voltage Reduce line voltage to at least 110% of
compressor motor rating
Short cycling Eliminate cause of short cycling
Unit short cycles Controller out of calibration Check controller software program
version; load new software in controller
and recheck unit performance, replace
controller
Refrigerant overcharge causing cycling on
high pressure cutout Purge system (R-134a or R-23) with
cycling compressor
Inefficient condenser operation causing
cycling on high pressure cutout Check condenser airflow, condenser
fan motor, condenser fan grille.
If R-23 compressor is cycling off, check
R-134a system operation and
refrigerant charge
Noisy unit Insufficient compressor oil Check compressor oil level on R-134a
and R-23 system. Add oil to proper
level
Loose mounting bolts Tighten mounting bolts
Oil slugging or refrigerant flooding back Add oil or refrigerant charge. Check
expansion valve adjustment.
Worn fan motor bearings Replace bearings or motor
Faulty compressor Repair or replace compressor
Condenser fan motor does
not operate Unit in Null, Heat or Defrost Check indicator lights. If unit is in Null,
Heat or Defrost, unit operation is
normal (no remedy required)
Loose line connection Tighten connections
Open motor internal thermal overload
protector Check for seized bearings or defective
thermal overload protector. Repair or
replace as necessary
Defective motor Replace motor
Detective condenser fan contactor Replace defective contactor
No condenser fan output signal from
controller Diagnose and replace condenser fan
relay, main relay board or controller
Evaporator fan motor(s)
does not operate Unit on defrost Check operating mode indicator LEDs
Loose line connection Tighten connections
Open motor internal thermal overload
protector Check for seized bearings or defective
thermal overload protector. Repair or
replace as necessary
Defective motor Replace motor
Defective low speed evaporator fan
contactor Replace defective contactor
No low speed evaporator fan output signal
from controller Diagnose and replace evaporator fan
relay, main relay board or controller
Condition Possible Cause Remedy