Atlas Copco XAS 175 Dd Instruction Manual page 30

XA(S)175 Dd
Problem
11. Compressor capacity or
pressure below normal.
(continued)
12. Working pressure rises
during operation and
causes safety valve (SV)
to blow.
13. Excessive compressor oil
consumption. Oil mist
being discharged from
air outlet valve (s).
14. Air and oil expelled from
air filter after stopping.
15. Compressor overheating.
30
Possible faults
e. Loading valve (LV) leakage past O-ring.
f. Oil separator element (OS) clogged.
g. Air intake throttle valve (TV) remains
partially closed.
h. Safety valve (SV) leaking.
i. Bleeder valve (BV) leaking.
j. Compressor element (CE) out of order.
a. Regulating valve (RV) incorrectly set or
defective.
b. Air leaks in regulating system.
c. Speed regulator (SR) malfunctioning.
d. Air intake throttle valve (TV) does not close.
e. Bleeder valve (BV) malfunctioning.
a. Restrictor in oil scavenging (SL) line
clogged.
b. Oil separator element (OS) defective.
c. Oil level too high.
a. If mainly air: check valve (CV) defective.
b. If mainly oil: oil stop valve (OV) defective.
a. Insufficient compressor cooling.
b. Oil cooler (OCc) clogged externally.
c. Oil system clogged internally.
d. Oil level too low.
e. Cooling fan (F) defective.
f. Oil separator element (OS) clogged.
g. Oil filter (OFc) clogged.
h. Oil stop valve (OV) stuck in closed
position.
Corrective actions
e. Remove and inspect valve.
Replace damaged or worn O-rings.
f. Have element removed and inspected by
an Atlas Copco Service representative.
g. Disconnect hose between throttle valve
housing and loading valve from the latter
and connect hose to independent
compressed air line. Repeatedly admit air
and listen for sound of valve. If sound is
not evident, remove unloader valve
assembly, dismantle and inspect.
Replace parts where necessary.
h. Remove and inspect.
Replace if not airtight after reinstallation.
i. Remove and inspect.
Replace, if necessary.
j. Consult an Atlas Copco Service
representative.
a. Adjust working pressure, see section 5.1.
Dismantle and inspect parts if valve does
not respond.
b. Check hoses and their fittings.
Stop leaks; replace leaking hoses.
c. Remove, dismantle and inspect piston
ring and its O-ring.
Replace worn or defective parts.
d. See 11g.
e. Remove and inspect valve.
a. Dismount, clean and refit restrictor.
b. Replace element.
c. Check for overfilling. Release pressure
and drain oil to correct level.
a. Repair valve and replace air filter
element.
b. Repair valve and replace air filter
element.
a. Relocate compressor.
b. Clean cooler; see section 4.6.
c. Consult Atlas Copco.
d. See section 4.4.
e. Replace fan.
f. Replace oil separator.
g. Replace oil filter.
h. Remove and inspect valve.