6
FIELD SERVICE GUIDE
Problems most frequently encountered with refrigerated dry
-
ers are water downstream of the dryer and excessive pressure
drop. Most causes can be identified and remedied by following
this guide.
Closed refrigeration systems are potentially
dangerous. Work on the refrigeration system must be done
only by a competent refrigeration mechanic. Do not release
fluorocarbon refrigerants to the atmosphere. All refrigerants
must be recovered per EPA requirements. Do not smoke when
a refrigeration leak is suspected. Burning materials may decom
-
pose refrigerants, forming a toxic gas or acids that may cause
serious injury and property damage. Before dismantling any
part of the dryer or compressed air system, completely vent
the internal pressure to the atmosphere.
PROBLEM
SYMPTOM
POSSIBLE CAUSE
REMEDY
Water Downstream of
Dryer
Refrigerant compressor not
running.
Leak in refrigeration system.
Contact your local distributor.
Compressor overheated.
Turn dryer off, wait 30 minutes; turn dryer on.
(Motor thermostat self-starting)
Compressor burned out.
Contact your local distributor.
No condensate discharging from
dryer.
Failure of drain.
Dismantle and clean strainer. Repair or replace
solenoid valve.
Dryer inlet air temperature too
high.
Aftercooler malfunction.
Check aftercooler discharge temperature and
reduce to dryer design condition (120°F max)
Excessive Pressure
Drop Across Dryer
Low outlet pressure.
Dryer undersized (may also cause
water downstream of dryer)
Check airflow and dryer capacity. Reduce airflow or
resize and replace dryer.
Dryer icing up. (check at separator)
Contact your local distributor.
Color Indicator Out of
Green Zone
Indicator in red zone.
Inlet air temperature too high.
Reduce aftercooler discharge temperature to design
conditions (See Engineering Data).
Condenser fouled or clogged.
Clean or replace condenser.
Inlet air temperature too high.
Reduce aftercooler discharge temperature to design
conditions. (See Engineering Data)
High ambient temperature.
Ventilate area.
Improper adjustment of expansion
valve.
Remove cap from the expansion valve and turn the
screw until the indicator is in the green zone.
Indicator in blue zone.
Improper adjustment of expansion
valve.
Adjust the expansion valve until the indicator is in
the green zone.
Low ambient temperature.
Increase ambient temperature to design conditions.
