Meritor Wabco System Saver 1000, Руководство по обслуживанию, Страница: 15 / 44

Section 2
Troubleshooting & Testing
MM-34
Revised 11-02 Page 11
No regeneration
cycle. No airflow
from purge valve
after initial purge
blast (dryer
decompression). Air dryer not connected to supply
tank or connections reversed at
dryer.
Regeneration valve not working.
One-way check valve installed in
supply tank.
Alcohol evaporator installed
between dryer and supply tank.
Blocked line/pinched line from
purge tank.
Yes
Yes
Yes
Yes
No
No
No
No
No
Yes
Verify proper dryer installation per
system diagram.
Replace regeneration valve.
Remove one-way check valve.
Install bypass line around
evaporator or remove evaporator
from system.
Clear/repair line.
Air dryer does not
purge when
compressor
unloads (no blast
of air from purge
valve). Air line between governor and air
dryer port 4 kinked or plugged.
Purge valve stuck closed.
Air governor not working
properly.
Cut-out pressure never achieved
by air compressor.
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Repair air line.
Replace purge valve.
Inspect air governor. Repair/replace
per manufacturer’s instructions.
Check for air leaks in system and
repair as needed. If no leaks in
system, check compressor output.
Repair/replace per manufacturer’s
instructions.
Air dryer purges
too often, perhaps
as frequently as
every 15 seconds,
accompanied by
excessive cycling
of the compressor. Leak in line between governor
and dryer port 4.
Leak in line between supply tank
and governor.
Excessive air system leaks.
Excessive air system demands.
Outlet check valve not seating.
Regeneration valve not shutting
off properly.
Air governor has less than 16 psi
range.
Leaking air compressor
unloader(s).
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
Yes
Yes
Yes
Yes
No
Yes
Yes
Repair air line.
Repair air line.
Repair leaks.
Increase air system capacity or
reduce air demand.
Inspect and replace outlet check
valve as needed.
Replace regeneration valve.
Replace air governor.
Inspect compressor. Repair/replace
per manufacturer’s instructions.
Air flows out of
purge valve entire
time compressor
is unloaded. Turbo cut-off valve not sealing.
NOTE: With U Series air dryers
the compressor unloads through
the dryer, so a steady flow of air
is normal.
Yes No Replace turbo cut-off valve.
Rapid “spitting” of
air from purge
valve in small
amounts.
Frequency varies
with engine speed. Holset E-type compressor used,
but no Econ valve installed.
Compressor not completely
unloading when cut-out pressure
is reached.
Yes
Yes
Yes
Yes
Install Econ valve to provide
make-up air to compressor.
Inspect compressor. Repair/replace
per manufacturer’s instructions.
Air leak at turbo
cut-off valve vent.
Hole burned in
piston. Temperature of air coming into
dryer is too high — not enough
cooling takes place before dryer
inlet. Yes Yes Move dryer farther from
compressor. Add additional
compressor discharge line before
air dryer. Add cooling coil or heat
exchanger before air dryer.
NOTE: Inlet air temperature must
not exceed 175°F (80°C).
Condition Possible Cause
Conditions May Occur In:
Solution
Regeneration
Style Air
Dryers Dedicated
Purge Tank
Air Dryers