sfarkas1
Feb 23, 2013, 01:53 PM
Had the code 33. It started right after I replaced the hot surface ignitor. While I was doing that I replaced the filter. The HSI replacement was of primary concern as obviously no heat. Beign so releieved about actually getting heat, I really wasn't paying too much attention to actual cycles of the furnace (gas over hot ignitor, fire,blower,evetually flame-off, blower continues to run and cools the furnace, then shuts down).
About a week after replcaing the HSI, thought I heard an odd cycle in the furnace. Tried to replciate the problem but couldn't. Anyway, one very early morning, having a coffee int eh very quiet house, I was able to catch the problem. Here it is:
Thermostat calls for heat
Gas starts and HSI starts, flame commences to heat furnace, then 30 seconds later, fan starts to distribute through the house. After a while, the thermostat seemingly tells furnace, OK, I've had enough and signals furnace to stop gas flow.
Here is the problem: occasionally, the fan shuts down almost immediately after gas flame turns off. This reults, about 45 seconds later, the re-issue of gas and HSI and the cycle starts all over again. This is the only time I 'caught' this code 33. In this 2nd cycle, the furnace ran a normal cycle with the flame shutting off and the fan continuing to blow for at least 90 secodns if not 2 minutes to 'cool' the furnace. At the end of the day, after running these 2 cycles, the home is at least 3 to 4 degree's C warmer than the thermostat setting.
I have pushed the re-set on the flame rollover switch and tried it a few times but cannot replicate the problem manually. This problem continues to be an occasional occurrence.
Is it possible that the thermostat may be a contributing element to the problem.
About a week after replcaing the HSI, thought I heard an odd cycle in the furnace. Tried to replciate the problem but couldn't. Anyway, one very early morning, having a coffee int eh very quiet house, I was able to catch the problem. Here it is:
Thermostat calls for heat
Gas starts and HSI starts, flame commences to heat furnace, then 30 seconds later, fan starts to distribute through the house. After a while, the thermostat seemingly tells furnace, OK, I've had enough and signals furnace to stop gas flow.
Here is the problem: occasionally, the fan shuts down almost immediately after gas flame turns off. This reults, about 45 seconds later, the re-issue of gas and HSI and the cycle starts all over again. This is the only time I 'caught' this code 33. In this 2nd cycle, the furnace ran a normal cycle with the flame shutting off and the fan continuing to blow for at least 90 secodns if not 2 minutes to 'cool' the furnace. At the end of the day, after running these 2 cycles, the home is at least 3 to 4 degree's C warmer than the thermostat setting.
I have pushed the re-set on the flame rollover switch and tried it a few times but cannot replicate the problem manually. This problem continues to be an occasional occurrence.
Is it possible that the thermostat may be a contributing element to the problem.