Bendix Commercial Vehicle Systems DRM DRYER RESERVOIR MODULE 3/07 - Manual (Page 13)

13
DRM ™ /AD-IS ® AIR DRYER TROUBLESHOOTING CHART (Continued)
SYMPTOMS CAUSE REMEDY
B. Excessive bends in
discharge line (water
collects and freezes).
C. Pressure protection
valve(s) in air dryer will
not open.
D. Refer to Symptom 4.
E. Refer to Symptom 7.
B. Discharge line should be constantly sloping from
compressor to air dryer with as few bends as
possible.
C. Replace air dryer (pressure protection valves are
not serviceable).
D. Refer to Symptom 4, Remedy A.
E. Refer to Symptom 7, Remedies A through D.
5. Can not build system
air pressure.
A. Kinked or blocked
(plugged) discharge line.
A. Check to determine if air passes through
discharge line. Check for kinks, bends,
excessive carbon deposits, or ice blockage.
6. Air dryer does not purge
or exhaust air.
A. Faulty air dryer purge
valve.
B. See Causes, B, E, and
G for Symptom #4.
A. After determining air reaches purge valve control
port by installing a T-fitting with a pressure
gauge into the governor unloader port, repair
purge valve if necessary.
B. Refer to Symptom 4, Remedies B, E, and G.
Also refer to Symptom 1, Remedy B.
7. Desiccant material
being expelled from air
dryer purge valve
exhaust (may look like
whitish liquid or paste
or small beads.)
A. Faulty dryer cartridge.
B. Excessive dryer vibration.
A. Replace AD-IS ® air dryer cartridge and/or
AD-IS ® air dryer.
B. Check reservoir mounting for looseness or
damage. Repair mounting and replace cartridge.
8. Unsatisfactory
desiccant life.
A. Excessive system
leakage.
B. Wrong vehicle application
for AD-IS ® air dryer.
C. Compressor passing
excessive oil.
A. Refer to Symptom 1, Remedy A.
C. Check for proper compressor installation; if
symptoms persist, replace compressor. Refer to
Bendix Advanced Troubleshooting Guide for Air
Brake Compressors (BW1971).
A. A slight “pinging” sound may be heard during
system build up when a single cylinder
compressor is used. If this sound is deemed
objectionable, it can be reduced substantially by
increasing the discharge line volume.
This can be accomplished by adding a 90 cubic
inch reservoir between the compressor and the
AD-IS
® air dryer.
9. “Pinging” noise
excessive during
compressor loaded
cycle.
B. Refer to Symptom 2, Remedy C.
A. Single cylinder
compressor with high
pulse cycles.