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IT Cooling
LogiCool InRak™
85
InRak™ Technical Manual 7462807 V1.11.0_04_2016
Troubleshooting
FAULT
POSSIBLE CAUSE
REMEDY / ACTION
Suction pressure too low.
Low evaporator airflow.
Depending on model:
Check fan motor speed set point or
Check fan motors, belts and drives
Flash gas (bubbles in sight glass) at expansion valve.
Investigate for refrigerant leaks,
repair and re-charge system.
Clogged filter drier (pressure /
temperature drop across it).
Replace.
Obstruction in expansion valve.
Inspect, clean or replace.
Condenser fan not operating - power on.
Motor / fan assembly jammed.
Isolate unit and check free rotation of
motor / fan assembly. If faulty - replace.
Fault at motor terminal box supply terminals.
Isolate and check electrical
connections are secure.
Motor internal overheat protector tripped.
Carry out continuity check at terminals
“TK” in motor terminal box. If tripped and
motor hot - check bearings. If tripped
and motor cold - replace motor.
Power supply failure.
Check power supply at circuit breaker.
Wiring to motor.
Check voltage at motor terminals.
Faulty motor windings / capacitor.
Motor humming would indicate
fault in motor or capacitor.
Minimum speed set too low.
Adjust head pressure controller to suit.
Faulty pressure sensor.
Check electrical connections are secure at
controller and pressure sensor. Replace
controller and sensor (as they are matched sets).
Faulty Controller.
Link wires “line” and “load” to bypass controller.
If motor runs full speed - replace unit.
Condenser fan runs too fast.
Condenser fans runs only slowly.
High ambient condition or excessive re-
circulation of air around condenser coil.
Check installation against design.
Minimum set speed setting incorrect.
Adjust as necessary.
Incorrect pressure setting.
Adjust sensor screw as necessary.
Faulty Fan Speed Controller.
Replace controller and sensor (as
they are matched sets).
Faulty pressure sensor.
Replace controller and sensor (as
they are matched sets).
Motor wired incorrectly.
Check against wiring diagram
- correct as required.
Motor / capacitor faulty.
Replace.