BENDIX® AD-IP® AIR DRYER TROUBLESHOOTING CHART
SYMPTOMS | CAUSE | REMEDY |
5. Constant exhaust | A. Air dryer purge valve is | A. With the compressor loaded, apply a soap solution |
of air at air dryer | leaking excessively. | on the purge valve exhaust, to test for excessive |
purge valve exhaust. |
| leakage. Refer to Technical Bulletin |
(Charge mode.) |
| Repair the purge valve as necessary. |
| B. Compressor fails to unload | B. Confirm the failure to unload by increasing & |
| (stop compressing air) and | decreasing engine RPM and noting change in the |
| the air dryer purge exhaust | rate of leakage and intensity of accompanying |
| makes “sputtering” or | leakage sound. Repair/replace compressor |
| “popping” sound. | unloaders. |
| C. Purge control line connected | C. Purge control line must be connected to unloader |
| to reservoir or exhaust port | port of governor. |
| of governor. |
|
| D. Purge valve frozen open - | D. Test the heater and thermostat as described in |
| malfunctioning heater and | Preventative Maintenance Section. |
| thermostat, wiring, blown |
|
| fuse. |
|
| E. Excessive system leakage. | E. See Symptom #1. |
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| F. Purge valve stays open - | F. Repair the purge valve and housing. |
| supply air leaks to control |
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| side. |
|
6. Can not build system | A. Inlet and outlet air | A. Connect compressor discharge to the air dryer |
air pressure. | connections reversed. | supply port. Reconnect the lines properly. |
| B. Check valve between the air | B. Test the check valve for proper operation. Repair |
| dryer and first reservoir. | or replace as necessary. |
| C. Kinked or blocked (plugged) | C. Check to determine if air passes through the |
| discharge line. | discharge line. Check for kinks, bends, excessive |
|
| carbon deposits, or ice blockage. |
| D. Excessive bends in | D. Discharge line should be constantly sloping from |
| discharge line (water collects | the compressor to the air dryer with as few bends |
| and freezes) | as possible. |
| E. Refer to Symptom 4, Causes | E. Refer to Symptom #4, Remedies E & F. |
| E & F. |
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7. Air dryer does not | A. Missing, broken, kinked, | A. Inspect control line from the governor UNL |
purge or exhaust air. | frozen, plugged or | (unloader) port to control port of air dryer. Test to |
| disconnected purge control | determine if air flows through purge control line |
| line. | when compressor unloaded. Check for undrilled |
|
| fittings. (See Symptom #4, Remedy C.) |
| B. Faulty air dryer purge valve. | B. After determining the air reaches the purge valve |
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| (Remedy A above), repair the purge valve. |
| C. See Causes, B, E, G for | C. Refer to Remedies B, E, G for Symptom #4. |
| Symptom #4. |
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