Symptom seen in
refrigeration system
Probable cause
Diagnosis
Remedy
• Press too high on both
low and high pressure
sides
• The low pressure piping
hot to the touch
Air entered in refrigeration
system
• Air present in
refrigeration system
• Insufficient vacuum
purging
- Check compressor oil to
see if it is see if it is dirty
or insufficient
- Evacuate air and charge
new refrigerant
8. Expansion valve improperly
Symptom seen in
refrigeration system
Probable cause
Diagnosis
Remedy
• Pressure too high on
both low and high
pressure sides
• Frost or large amount of
dew on piping on low
pressure side
Trouble in expansion valve
• Excessive refrigerant in
low pressure piping
• Expansion valve opened
too wide
- Check expansion valve
- Replace if defective
9. Defective compression compressor
Page 4 of 7
24.04.2008
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