TWP/TWB200 – TWP/TWB9000
72
TROUBLESHOOTING
Dryer not operating; no lights on
  - Blown control fuse: replace fuse.
  - No power: apply correct power, verify quality of power source.
  - Controller inoperative: replace controller.
  - Control transformer defective: replace transformer.
  - Program crashes: replace SD card.
Power light on, other lights off, dryer does not operate
  - Cycle has not been initiated: press start button.
Dryer not operating; lights on, dryer does not switch
  - Control air valve is closed: open control air valve; check condition of control air lter element.
  - No air supply to dryer inlet: connect air supply.
  - Dryer in Power Saving State: Disable Dewpoint Demand to go back to a standard timing cycle.
No heat in regenerating bed
  - Regenerating tower will not blow down: dryer not sequencing or in dewpoint demand mode: see above.
  - Bad output, solenoid, or exhaust: replace part or correct issue.
Dryer cycles, no heat
  - Dryer in heatless backup mode: switch to heated mode and press start button.
  - Overtemp shutdown engaged: Check setting and press reset; if overtemp shuts down dryer again
     consult factory.
  - Thermocouple disconnected or defective: reconnect or replace.
  - Purge ow set to low: adjust purge setting to spec (TWP dryers only). 
Insufficient Heat
  - Low purge ow: adjust purge setting to spec (TWP dryers only).
  - Clogged mufer: clean, replace, or remove.
  - Moisture load too high: adjust dryer inlet air ow conditions to within spec.
  - Defective thermocouple or controller: replace.
High Outlet Dewpoint or Moisture Downstream
  - Dryer not cycling: see dryer not operating.
  - Insufcient or no heat: see above.
  - Incorrect purge rate: adjust purge setting to value specied on purge tag or manual.
  - Capacity of dryer exceeded: adjust inlet ow rate, inlet air temperature, and inlet air pressure to within
     specied operating conditions for the model.
  - Liquid water present at dryer inlet: check water level in separators, receivers, prelters, and operation of 
     associated y-strainers and auto drains. Check condition of lter elements or check differential 
     pressure gauges.
  - Desiccant worn out, contaminated, or insufcient quantity: replace desiccant or add correct amount.
  - Reduced regeneration: see Back Pressure In Regenerating Tower.
  - Leaking bypass valve: replace valve.
  - Undried air from another source mixing downstream of dryer: remedy.