Heatilator GNBC33EE

I fpund a manual here https://www.manualslib.com/manual/912944/Heatilator-Gnbc30.html?page=11#manual

So it is a B-vent type fireplace with a milivolt type gas valve. According to page 11 of the manual, it has a high limit safety switch which would shut down the fireplace if it exceeds the maximum allowed temperature limit or if the limit switch is defective.

The pilot has 2 safety devices, a thermocouple to hold the pilot on once the thermocouple Has warmed up and the thermopile which holds the valve open for the main burner. In addition, you also have a switch to turn on/off the main burner. Any of these systems could develop a fault.

So can you confirm that your fireplace is vertically vented, and what height ? Does that vent run in a chase on the outside of the house (on an exterior wall) ? What fuel are you using ? NG or LP ? Could you take a picture of the pilot flame ?

staceylavonne said:

Hello all!

I have a Heatilator GNBC33E gas fireplace, installed in 2001. It starts up and runs for a few minutes and shuts off. Sometimes it starts back up, sometimes it's off until I flip the switch off and back on. I'm not sure what to do, I've seen several different solutions to the problem, but I have no idea where to even start. Any and all advice is welcome!

Thanks in advance!

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So the pilot burner is staying lit ----it's the main burner which is cycling on/off or not lighting reliably, is that right?

A likely source of a problem is a dirty pilot burner which is not keeping the pilot generator/thermopile hot enough to reliably generate enough electricity to open and hold open the main burner gas valve.

Describe the appearance of the pilot burner flame in detail. It should look like a small blowtorch, with a sharp blue flame that engulfs both the pilot generator thermocouple and has enough flame to light the main burner reliably when the gas turns on.

It should not have yellow tips, be a soft flame like a candle flame or fail to engulf the pilot generator and the thermocouple.

KeithO said:

I fpund a manual here https://www.manualslib.com/manual/912944/Heatilator-Gnbc30.html?page=11#manual

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Thank you for finding the manual on the fireplace, Keith. I usually find that's a big help in understanding what kind of equipment we are looking at and often what unusual problems may be occurring.