TROUBLE SHOOTING CHART
SYMPTOM
CAUSES
CHECK & CORRECTIVE MEASURE
Loss of oil pressure.
1. Loss of oil from compressor due to:
(a) Oil trapping in system.
(b) Compressor short cycling.
(c) Insufficient oil in system.
(d) Operation at excessively low
suction pressure.
2. Excessive liquid refrigerant returning
to compressor.
3. Malfunctioning oil pump.
4. Restriction in oil pump inlet screen.
1. (a) Correct the system piping.
(b) Trace out the wiring/defective controls/
components, etc. and correct it.
(c) Add oil.
(d) Check the superheat of expansion
valve and other possible causes
like clogged filter, low CFM, iced
evaporator etc. and correct it.
2. Check the system for correct super
heat and other possible causes like
clogged filter, low CFM, iced evapo-
rator, etc. and correct it.
3. Repair or replace it.
4.Clean/replace it (oil change recommended).
Unit noisy.
1. Loose parts or mountings.
2. Tubing rattle.
3. Bent fan blade causing vibration.
4. Fan motor bearings worn.
1. Find and tighten.
2. Tighten the pipe support.
3. Replace blade.
4. Replace motor.
Space temperature too high.
1. Control setting too high.
2. Expansion valve too small.
3. Cooling coils too small.
4. Inadequate air circulation.
1. Reset control.
2. Use larger valve.
3. Add surface or replace.
4. Improve air movement.
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