Trane RAUL 190, Manual

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18 RAU-SVX01G-GB
Troubleshooting guide
These are simple diagnostic hints. If there is a breakdown, the Trane Service offi ce should be contacted for
confi rmation and assistance.
Problems symptoms Problem cause Action recommended
A) The compressor does not start up
Compressor terminals are live but motor
does not start
Motor burned out. Replace compressor
Contactor motor not operational. Coil burned out or broken contacts. Repair or replace.
No current ahead of motor contactor. a) Power cut.
b) Main power supply switched o
ff .
Check fuses and connection.
See why system tripped.
If system is operational, switch on main
power supply.
Current ahead of fuse, but not on contactor
side.
Fuse blown. Check motor insulation. Replace fuse.
Low voltage reading on voltmeter. Voltage too low. Contact power Supply Utility.
Starter coil not excited. Regulation circuit open. Locate regulation device which has tripped
out and see why. See instructions concerning
this device.
Replace compressor.
Compressor does not run.
Compressor motor ”groans”.
High pressure switch tripped to contacts
open on high pressure.
Discharge pressure too high.
Compressor sticking
(damaged or sticking components).
Discharge pressure too high See instructions for “discharge pressure
high”.
B) Compressor stops
High pressure switch tripped.
Over current thermal relay tripped. Discharge pressure too high. See instructions for “discharge pressure
high”.
a) Voltage too low.
b) Cooling demand too high, or condensing
temperature too high.
a) Contact Power Supply Utility.
b) See instruction “discharge pressure too
high”.
Motor temperature thermostat tripped.
Anti-freeze security tripped. Not enough cooling fl uid. Repair leak. Add refrigerant.
C) Compressor stops just after its start
Suction pressure too low.
Filter drier iced up. Filter drier clogged. Replace fi lter drier.
D) The compressor keeps running
without stopping
Temperature too high in areas requiring air-
conditioning.
Excess load on cooling system. Check thermal insulation and air-tightness of
areas requiring air-conditioning.
E) Loss of oil in compressor
Oil level too low in indicator. Not enough oil. Contact Trane o ffi ce before to order oil
Gradual fall in oil level.
Suction line too cold.
Compressor noisy Filter drier clogged.
Liquid
fl ows back to compressor.
Replace fi lter drier.
Adjust superheat and check bulb fi xing of the
expansion valve.
F) Compressor noisy
Compressor knocks. Components broken in compressor. Change compressor.
Suction line abnormally cold. a) Uneven liquid fl ow.
b) Expansion valve locked in open position.
a) Check superheat setting and fi xing of
expansion valve bulb.
b) Repair or replace.