5 - 6
Troubleshooting Guide
4.
Check for pilot gas pressure at on-stream chamber exhaust
valve’s pilot tubing connection.
If pilot pressure is present, Shutdown and Depressurize
Dryer. Disassemble, clean and inspect the Switching Valve.
Replace all worn or damaged parts as noted.
1.
Check indicator lights at solenoid block to determine whether
energized. Indicator light should be lit if the solenoid coil is
energized. If not, open control enclosure and check MEC
Board for output signal to solenoid valve.
a) If voltage is present and the indicator at the solenoid block is
not lit, Shutdown and Depressurize Dryer. Provide a
separate pilot gas source.
With the dryer controls de-energized, press the manual
override on solenoid valve to determine if functioning. If
functioning mechanically (the purge exhaust valve should
open), the solenoid valve coil is defective. Replace solenoid
valve coil.
Note: The dryer MUST be depressurized to change coils
on a solenoid.
b) If voltage is present and the purge exhaust valve doesn't
open when manual overriding the solenoid valve, the sole-
noid valve is defective. Replace solenoid valve.
c) If voltage is not present, replace MEC Board.
1.
Shutdown and Depressurize Dryer. Replace pressure sen-
sor.
4.
During Repressurization Cycle.
Purge Exhaust Switching Valve has failed to
close due to fouled or worn valve internals.
Valve Failure Alarm with excessive pressure ex-
hausting through muffler. BOTH chamber pres-
sure gauges read normal system pressure.
1.
During Depressurization Cycle.
Off-stream chamber's Purge Exhaust Valve
has failed to open due to the associated so-
lenoid valve's (A or D) failure to energize.
Valve Failure Alarm.
1.
Damaged or out of calibration pressure sen-
sor.
PROBLEM/POSSIBLE CAUSE
CHECKS AND REMEDY
