FAULT
CAUSE
REMEDY
F All cylinders out of
action while compressor
is operating
1. Control pressure for valve lifting mechanism
too low
1. See K
G Too high oil
consumption
1. Type of oil not according to lubrication oil
table 3.1 (too thin oil)
1. Consult installation engineer
2. Compressor operates onloaded too
frequently
2. Consult installation engineer
3. No return from oil separator
3. Check the operation of float valve
in oil separator
4. O-rings around control piston of valve lifting
mechanism worn or defective
4. Replace O-rings
5. Non-return valve at the bottom of suction
chamber in cylinder defective
5. Replace valve*
6. Worn out oil scraper rings
6. Replace rings*
7. Loss of oil due to leakage
7. Repair
H Too high oil pressure
during normal
operation at working
temperature
1. Lubricating oil pressure regulator not
adjusted properly or defective
1. Re-adjust or repair
2. Defective oil pressure and/or suction
pressure gauge
2. Repair or replace
J Too low oil pressure
1. Tool little amount of oil in crankcase
1. Top up oil
2. Oil suction and/or discharge filter is dirty
2. Clean or renew
3. Lubricating oil pressure regulator not
adjusted properly or defective
3. Re-adjust or repair
4. Liquid refrigerant in crankcase
4. See E
5. Defective oil pressure and/or suction
pressure gauge
5. Repair or replace
6. Too large bearing clearance
6. Renew bearings*
K Too low or no control
pressure
1. Hydraulic time delay valve in oil pump is
jammed
1. Dismantle and repair oil pump*
2. Relief valve in oil pump leaks
2. Disassemble and repair valve
The operation marked with an * in the column "Remedy" should be carried out by the installation engineer
Refrigeration Division
Grasso
10. FAULT FINDING TABLE
Page 10.2
Refrigeration Compressors Series RC9
v002.97.10.en
