Sterling GF-150 User Manual

22

  Q. Cold air is delivered during 

heater operation.

  R. High limit tripping.

   S.  Power ventor will not run.

 

T. Power ventor turns on and off 

during operation.

  U. Power ventor will not stop.

 1. 

Refer 

to 

“Operation”.

 2. 

Refer 

to 

“Operation”.

  1. Burner orifi ces may be too large, verify 

and replace.

  2. Check for proper voltage, ensure fan 

blade is correct.

   3. Check operation of switch, did the switch 

open when unit is running or is the switch 
open during start-up.

  4. Check for 24v on line side of the high limit. 

Constant voltage should be recorded if not 
control board is suspect. Check fl ash code.

 1. 

Check all wring in the power vent circuit to 
ensure good connection, including “Neutral”.

   2.  Check for 115v between motor leads and 

check amp draw of motor. Replace if needed.

   3. Check for continuous 115v on terminal 

“CBM Blower” and neutral during call for 
heat. If not present and all checks are 
normal, replace.

  1. Check power ventor circuit per wiring 

diagram.

 2. 

Check motor voltage and amp draw to motor 
name plate, replace if motor found defective.

  3. Check for continuous 115v on terminal 

“CMB Blower” during call for heat, replace 
board if found defective.

  1. Check power ventor circuit per wiring 

diagram.

 2. 

 

Heater is in lockout mode check fl ash code 
table for problem.

  3. No fl ash codes present along with no call 

for heat, replace control board.

  1. Incorrect manifold pressure or input.
   2. Air throughput too high.

  1. Unit is over fi red.

  2. Air fl ow is low.

 3. 

Defective 

switch.

  4. Defective control board.

  1. Loose wiring or connections.

  2. Motor overload is tripped or bad motor.

   3. Bad control board.

  1. Power ventor improperly wired.

  2. Motor overload cycling or defective motor.

  3. Defective control board.

  1. Power ventor improperly wired.

  2. Main burner did not light on call for heat.

  3. Defective control board.