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R.G., HVAC Technician
Category: HVAC
Satisfied Customers: 319
Experience:  20 yrs. experience as HVAC technician, state certified contractor.
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i have a gmpn100-4 revA, motor starts, pilotless ignition does

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i have a gmpn100-4 revA, motor starts, pilotless ignition does not glow, 2 clicks then systems shuts down. what can i do i already replaced igniter, but still doesnt come on.

R.G. : Hi, I'm R.G., sorry you're having trouble today. I will do my best to assist you in resolving your issue.
R.G. : by vaccuum hose do you mean hose from press. Switch?

from top of blower motor, and red light on circuit board is steady on

R.G. : Do you have a multi meter to test with?

a small unfancy GE2527


it has DCV, ACV, DCA, and ohms

R.G. : Okay the steady light indicates no fault, so possibly a faulty control board. Have you checked the rollout switches. I think your unit has 2 they will be near burner and have 2 wires connected and a red reset button in the middle, press reset to make sure they are not tripped

still there ?

R.G. : Yes sorry was trying to locate manual,for your unit

oh ok



R.G. : Can you locate rollout switches and make sure they are not tripped by pressing red reset.
R.G. : No problem thanks for your patience

ok am


didnt work


sorry was pressing on sensors, where are rollout switch

R.G. : Okay if any of the limits were not made we should get a fault code on board. Can you set your meter to ACV unplug the ignitor put one test lead on each wire coming to ignitor and cycle furnace to see if you are getting voltage to ignitor.
R.G. : Rollouts should be on each side of burner small disc shaped with 2 wires attached and red reset in middle.
R.G. : we need to verify if we are getting voltage to ignitor

0 volts thru meter


tried 3 times

R.G. : Okay thanks

let me guess bad circuit board

R.G. : We can go through and check each limit switch, but if board was working properly it would show a fault code if limit was the problem. Sounds like bad circuit board.

can i light furnace manually?

R.G. : No, with bad circuit bad that wouldn't be safe
R.G. : Board

ok, can i install new board myself?

R.G. : Sure, you just turn power and wires unplug off old board and plug into new one
R.G. :
R.G. : Above is link to service manual you can bookmark for future reference

thank you, XXXXX XXXXX is a B18099-13 according to old board

R.G. : You should be able to find one at any local HVAC supply, but can usually get cheaper online if you can wait for delivery

i looked online before and all places have a B18099-13S as replacement i didnt want to order if this wasnt problem they run around $200.00 and would have hated to that out window if that wasnt the problem.



R.G. :
R.G. : Look at address above they list them for $137
R.G. : You may get cheaper if you can find one on eBay
R.G. : I just found one on eBay for $58.50
R.G. : One minute and I will give you link to it

cool, where are you located if i can ask?


just curious because of time its 1211 am here

R.G. :
R.G. : Above is one for 56 and free shipping
R.G. : Alabama
R.G. : It's 1130 here
R.G. : Let me know if you need any further information and please remember to rate answer before leaving if satisfied with my service tonight. Thanks

cool, my gf from alabama, she never told me city though just the state. and will do. THANK YOU VERY MUCH.

R.G. : Your welcome, I'm in north Alabama near Huntsville

dang small world my ex platoon sgt was from huntsville

R.G. : Thanks for your service MUCH appreciated
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