Whirlpool Furnace Short-cycles
#1
Whirlpool Furnace Short-cycles
Hello-
I have a 17 year old Whirlpool gas furnace that is trying to start, but can not. The thermostat calls for heat, the igniter sparks, the gas comes on and ignites for a second or two, then goes out. It continuously cycles like this several times a minute. From time to time the blower will come on for a minute then turn off. I was able to get it started this morning by turning off power to the furnace for several minutes then turning it back on. It started and ran fine for one full cycle after that.
Thanks for your help.
I have a 17 year old Whirlpool gas furnace that is trying to start, but can not. The thermostat calls for heat, the igniter sparks, the gas comes on and ignites for a second or two, then goes out. It continuously cycles like this several times a minute. From time to time the blower will come on for a minute then turn off. I was able to get it started this morning by turning off power to the furnace for several minutes then turning it back on. It started and ran fine for one full cycle after that.
Thanks for your help.
#3
My unit has a combination igniter / sensor. It didn't look bad though I did clean and and the connections with steel wool. The furnace is still experiencing the same problem. It will get to the point that the burners lite and then it self extinguishes after a couple seconds or less.

#5
Short-cycle Whirlpool
My furnace is doing the same thing. If you turn up the thermostat, you'll hear the exhaust fan start. Then a click and soft "whoompf" of the flames starting. Within five seconds the flame stops and the cycle starts over. This "Click,Whoompf" cycle is waking us up at night. I'll look at the flame sensor thingy, clean and test it with an ohmeter and get back to you with my findings.
Thanks,
Mike
Thanks,
Mike
#6
Short-cycle whirlpool
Well, there is no flame sensor near the burners. Just an igniter that's connected to a module with a spark plug wire. There is a fan limit switch that turns as it heats up. It is connected to a relay that controls the main blower. Hmmmmm.
Mike
Mike
#7
Short-cycle update
Well, now I understand that the igniter is also the flame sensor. Somehow, when the flame from the pilot is running over the tip, the ignition module senses a current to ground. The advice from an HVAC guy was to make sure the tip is clean and make sure the ground wire has a good connection to the pilot/igniter. Having done that, the problem is still happening. I jumpered out the thermostat to prove that out and it still short cycled. I found the instructions for the ignition module on the web:
http://hbctechlit.honeywell.com/Defa...FTOKEN=3262216
The troubleshooting flowchart included in the .pdf file basically says "replace the module".
I'll let you know if that was the problem.
Mike
http://hbctechlit.honeywell.com/Defa...FTOKEN=3262216
The troubleshooting flowchart included in the .pdf file basically says "replace the module".
I'll let you know if that was the problem.
Mike