Trane AquaStream CGWN 205 Installation Operation & Maintenance page 59

F) Compressor noisy
Compressor knocks.
Suction duct abnormally cold.
G) Insufficient cooling capacity
Thermostatic expansion valve "whistles".
Excess pressure drops through filter drier
Excessive superheat.
Insufficient water flow.
H) Discharge pressure too high
Condenser abnormally hot.
Chilled water leaving temperature too high.
Condenser air output too hot.
I) Suction pressure too high
Compressor operates continuously.
Suction duct abnormally cold.
Refrigerant flows back to compressor.
J) Suction pressure too low
Excessive pressure drop through filter drier.
Refrigerant does not flow through thermostatic expansion
valve.
Loss of power.
Superheat too low.
K) Insufficient cooling capacity
Low pressure drops through evaporator
CG-SVX06D-E4
Maintenance
Components broken in compressor.
a) Uneven liquid flow.
b) Expansion valve locked in open position.
Not enough refrigerant.
Drier filter clogged.
Superheat not properly adjusted.
Chilled water pipes obstructed.
Presence of uncondensable liquids in system, or excess
refrigerant.
Overload on cooling system.
Reduced air flow. Air intake temperature higher than
specified for unit
Excess cooling demand on evaporator
a) Expansion valve too far open.
b) Expansion valve locked in open position.
Filter drier clogged.
Expansion valve bulb has lost its refrigerant.
Expansion valve obstructed.
Excessive pressure drops through evaporator.
Low water flow rate.
Change compressor.
a) Check superheat setting and fixing of expansion valve
bulb.
b) Repair or replace.
Check refrigerant circuit tightness and add refrigerant.
Replace.
Check adjustment of superheat and adjust thermostatic
expansion valve.
Clean pipes and strainer.
Purge uncondensable fluids and drain off excess refrigerant.
Reduce load on system.
Reduce water flow if necessary.
Clean or replace air filters. Clean coil. Check operation of
fan motors.
Check system.
a) Check for superheat and check that expansion valve bulb
is secure.
b) Replace.
Replace the filter drier.
Replace the bulb.
Replace.
Check adjustment of superheat and adjust thermostatic
expansion valve.
Check water flow rate. Check state of strainer, check for
obstruction in chilled water pipes.
Check pressure switch contact in water.
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