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CENTAC TROUBLESHOOTING GUIDE
3
CST-TP0007
1994 Ingersoll-Rand Company
Date of issue: January, 1999 Supersedes: 16-dec-94
Low System Air Pressure
Cause
Solution
1. Incorrect setpoint.
Adjust.
2. Incorrect valve calibration.
Restroke valves.
3. Bad controller.
Repair or replace.
4. Dirty inlet filter.
Replace filter elements.
5. Compressor operating unloaded.
Switch selector switch to load.
6. System demand greater than
compressor capacity.
Check for excessive air usage like open
valves, leaking fittings, etc., and correct.
Start additional compressor. Recommend
that customer purchase another Centac if
additional capacity is required.
7. Compressor block valve closed.
Open valve.
8. Incorrect controls calibration.
Adjust controls.
9. Discharge check valve sticking.
Repair or replace.
10. System air pressure sensing point in
wrong location.
Relocate control air connection
11. Excessive pressure differential across
air dryer.
Investigate and correct.
12. Too low CLH setting.
Increase setting (Do not exceed
FLA+SF).
13. Leaking bypass valve.
Investigate and correct. Replace seat;
free up sticking valve.
14. Bypass valve stays open; inlet valve
functions normally.
Lower CLL to activate bypass valve on
MP3 panel. Ensure 2TR is operating
properly on Electro-Pneumatic panel.