Airedale Condensing Units (CU) 3kW - 80kW - Manual (Page 24)

CUS 15 - 60 / HCU 20 – 30D
Condensing Units
Chiller & Condensing Units
Installation & Maintenance:Part No: 6259592 IM 07\14
24
Troubleshooting
REFRIGERATION
FAULT POSSIBLE CAUSE REMEDY / ACTION
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. High ambient condition or excessive re-
circulation of air around condenser coil.
Check installation against design.
Minimum speed setting incorrect. Adjust as necessary.
Incorrect pressure setting. Adjust sensor screw as necessary.
Faulty Controller. Replace controller and sensor (as they are
matched sets).
Faulty pressure sensor. Replace controller and sensor (as they are
matched sets).
Condenser fans runs only
slowly. Incorrect pressure setting. Adjust sensor screw as necessary.
Faulty 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.