20
HB Series Desiccant Dryer Models 150-8000
ingersollrandproducts.com
12.0 TROUBLESHOOTING
A
NOTICE
The Heater High Temperature Alarm halts the Microprocessor Control
program. Prior to reinstating dryer, note the position of all valves. This
is critical in determining the possible cause of the alarm condition.
A
NOTICE
To reset the Heater High Temperature Alarm, reset the Microprocessor
Controller using the RESET button and manually reset the Heater High
Temperature safety in the control enclosure.
Check purge flow settings (Heatless Mode).
Check blower intake filter.
Check purge flow adjustment valve.
Check pressure source.
Check flow rate and cause for increased demand.
Check aftercooler, clean and service as necessary.
Check air/moisture separator and pre-filter. Replace
dryer desiccant if necessary.
Install suitable pre-filter. Replace dryer desiccant.
Check flow rate and cause for increased air demand.
Check pressure source.
Check inlet valve. Verify inlet valve is closed to purging
tower (0 PSIG tower).
Check gauge against tower gauges when in switching
sequence. Replace gauge as required.
Check power input.
Check no-loss drain valve.
Check pilot air line. Check that control air line filter is
clean. Check regulator setpoint.
Check switch. Open pressure: > 65 psig; close pressure:
< 40 psig
Check purge valve and its solenoid valve.
Check that repressurization circuit is sending control signal.
Check solenoid valve. Repair and replace if necessary.
Replace contactor.
Replace thermocouple.
Replace temperature control.
Contact Ingersoll Rand Distributor / Factory
Check voltages and current to heater and blower.
Correct problem and reset blower motor starter.
Remove and clean or replace blower filter. Reset blower
motor starter.
Replace control solenoid valve. Reset blower motor starter.
Repair or replace valve. Reset blower motor starter.
Replace check valve. Reset blower motor starter.
Verify and correct sizing of exhaust piping. Reset blower
motor starter.
Insufficient purge rate / I
Inlet air/gas pressure below design condition.
Flow rate higher than design condition.
Inlet temperature above design condition.
Entrained water entering desiccant bed.
Desiccant contaminated by oil.
Excessive flow rate.
Inlet pressure below design condition.
Air is leaking across valve.
Improper calibration
No input power
Defective no-loss drain valve
No pilot air / Low pilot air pressure
Defective pressure switch
Faulty purge valve
Purge valve does not open. Purge valve stuck
in closed position.
Contactor stuck closed.
Defective thermocouple
Defective temperature control
Valve switching failure
Improper voltage and / or current to heater and
blower
Dirty Blower Intake Filter
Purge outlet valve not open
Repressurization valve worn.
Purge flow check valve sticking.
Purge exhaust line restricted.
Elevated dew point
Excessive pressure drop in
dryer
Excessive back pressure in
regenerating tower (Above
5 PSIG).
Excessively high pressure at
the purge gauge (Blower and
Heatless Modes)
Failure to Shift
(Switching Failure)
Failure to Shift
(Dryer fails to pressurize.)
Failure to Shift (Dryer fails to
depressurize.)
Heater High Temp. Alarm
(Heater runs continuously)
Heat High Temp. Alarm
(Loss of flow across heater)
Blower and / or Heater not
working due to overload on
blower motor starter tripping.
PROBLEM
PROBABLE CAUSE
CORRECTIVE ACTION
120.26 Dryer - Operation, Installation, Maintenance Manual, and Parts
