[benidle]

I have a comfortmaker (4-5 years old) GNE075B12A2 with a honeywell sv9501m2056 that won't stay lit or turn on. The pilot will come on for one to two minutes and then it shuts off. it begins with a strong flame that dulls to a low blue flame before growing again and then extinguishing. While the blower works, the fan will not come on unless set to on at the thermostat. From reading here i am thinking its a malfunctioning sensor detecting an overheat in the heat box but...??? the field twinning connection wouldnt need to be reset, would it? its now at off on on (but i am understanding that only has to do with linking two furnaces? I am still hoping to find the magic switch that will restore heat.) There is no warm air and the fan doesnt run on auto, and only a weak draft comes through the vents from the blower. the ac worked all summer but no heat. i recently changed the filter. any suggestions would be greatly appreciated, if for nothing else, increasing my understanding of things that make my life somewhat comfortable.

 

[HVAC Doc]

That model of Honeywell gas valve is notorious for trouble. The first generation Smart valves would cause intermitant lock outs and sense no flame even with a new ignitor/sensor assembly installed. It is not just Comfortmaker who used these and had troubles either. The twinning kit shouldn't be an issue unless of course you have 2 furnaces twinned together. Get a tech out to check out the valve and make sure all your safeties/controls are working properly. Also, some models of Comfortmakers had a 5yr. parts warranty, is yours one of them? If it is, you would at least only pay for labor and not the parts themselves.

 

[benidle]

thanks you

thank you for the heads up on the warranty. No magic switch to switch though, eh? Should the tech try the ignitor first, or just cut to the chase and replace the gas valve? Or will they have ways of testing it out. once again, thank you for the prompt and helpful reply.

 

[HVAC Doc]

No magic switch sorry. Yes the tech can test the main control and the gas valve both and determine where the fault is. Most likely, it is the valve with their history but there are always those exceptions to the rule.

 

[benidle]

it was the gas valve!!!!!

Thanks again. the tech just left. after replacing the thermocoupler and the senseor they waited for an overnight delivery and replaced the faulty gas valve. anyway, thanks again for the informative reply, that made me realize the problem was beyond my skill or knowledge level to fix.