[SOLVED] gas fireplace won't start-up - pilot is lit

[funkdys]

Hello all -

first post on this forum, so please excuse any newbie errors...

I have a gas fireplace at home that I haven't used in a couple of years. I had turned the pilot off after I used it last. I tried to start it back up yesterday, and the pilot started right up. I have a wall switch that controls the gas flow and turns the fireplace on. When I try to flip the switch to turn the fireplace on, it does nothing 9 times out of 10. Occassionally the flames will come and stay lit for a couple of minutes before going out again, and then nothing. I don't smell any gas when the fireplace switch is on but the flame isn't present. Not sure where to look to try and debug this issue... any helpful pointers would be greatly appreciated!

Merry Christmas!

[BobK207]

Funny thing......I just went through a very similar process with our gas log set today.

I tried to light the pilot & it would light but not stay lit

So.... I turned off everything.....the electrical switch on the log set (my set doens't have a wall switch), the manual valve on the log set to "off" postion and the recessed gas c*ck on the side of the fireplace.

I did the start up process....open gas c*ck, turn manual valve to "pilot" & depress, light pilot and hold knob in for ~2 minutes, turn manual valve to "on".

Pliot stayed lit......flipped electrical switch to "on" and the log set fired up & has stayed burning for a few hours so far.

I have no idea why the pilot wouldn't stay lit but turning everything off seems to have fixed it. ????

Give the "total shutdown and wait a few minutes before a re-start" a try.

cheers Bob

[ransley]

Does it have a thermocouple on the pilot a maybe 2" round metal piece with a wire on it going to a gas valve, that might be bad I used a propane torch to heat one up once, its probably a standard item even some place like Sears might have for cheap. But I am guessing and dont know if what I recomend is safe.

[Tom Lachance]

First of all, need to know what kind of "fireplace" it is:

1. Direct vent or natural vent
2. Free standing, zero clearance or masonry insert
3. Vented or unvented gas log.
4. ODS or thermocouple/thermopile The above combinations can be used in a number of ways.

Thermocouple/thermopile assemblies have 2 separate circuits powered by the their respective devices. Thermocouple = 20 millivolts (+/-) Thermopile = 750 millivolts (+/-) If the pilot lights and stays lit, the problem isn't with the pilot circuit. If the main burner doesn't light, the problem is in the main burner circuit. Some units have more than 1 switch controlling them. The supplied switches on the units are notoriously unreliable. The gas valve generally has connections for the main burner labeled TH, TP, and TH/TP. The main burner is operated by a switch that makes a circuit between the TH and TH/TP connections. Is there a remote installed on the fireplace? If so, there is usually a switch on it labeled on/remote/ off. If you move the switch to on and the main burner lights, check the batteries in both the remote and the receiver. If it doesn't light, check the other switches/controls connected to the above connections.

The above procedure assumes the control valve is in the "ON" position and not in "PILOT".

[Chris]

These gas log sets have to be cleaned every so often. Dust gets in the pilot hole and the symptoms you describe happen.

I had two phone calls this week from people with gas fire places and heaters and both had the same problem. DIRT!!!

Chris

[funkdys]

Happy new year to all!

I checked the fireplace and couldn't figure out the make - the card that came with it says XDVR-38RMN, but I couldn't find anything based on that description in my Google search. I did see a circuit diagram that mentions Thermopile. It's a masonry insert.

The pilot does light easily and stays lit, so as you suggested, that's not where the issue is. I did clean everything out and then tried to get the fireplace going again to no avail... There is NO remote with the fireplace - just the wall switch. I checked all the circuit breakers and saw no issue there. When I flip the wall switch, nothing happens. I don't smell gas when I flip the switch... Would a bad thermopile result in these symptoms?

Appreciate any additional pointers you may be able to offer.

Thanks!

[Tom Lachance]

If the pilot is lit, make sure the gas valve control is in the "ON" position. Check around the gas valve area for an "off/on" rocker switch. If found, place it in the ON position. If the burner lights, the problem is in the wiring to the wall switch. There wouldn't be any issue with circuit breakers. The wall switch connects only to the gas valve. If you have a VOM or a continuity tester, disconnect the wires

[John Galbreath Jr.]

Go to the gas valve, look for three terminals. One will be marked TH, one TH-TP, and one TP. When the TH and the TH-TP are connected, the fire lights if the gas valve is in the on position and you have a pilot. There is no power here, so you can jump with a paper clip. But when you do *** THE FIRE WILL COME ON ***, so be careful and be prepared. If it does light, then the problem is in your wiring to the wall switch. If is does not come on, the problem is in the gas valve. The wiring is the likely culprit.

Happy new year to all!

I checked the fireplace and couldn't figure out the make - the card that came with it says XDVR-38RMN, but I couldn't find anything based on that description in my Google search. I did see a circuit diagram that mentions Thermopile. It's a masonry insert.

The pilot does light easily and stays lit, so as you suggested, that's not where the issue is. I did clean everything out and then tried to get the fireplace going again to no avail... There is NO remote with the fireplace - just the wall switch. I checked all the circuit breakers and saw no issue there. When I flip the wall switch, nothing happens. I don't smell gas when I flip the switch... Would a bad thermopile result in these symptoms?

Appreciate any additional pointers you may be able to offer.

Thanks!

[BobinDurham]

I had the EXACT same problem. What appeared to be a good pilot was giving me

540 millivolts at the terminals, but when I turned the valve from pilot to on, the fireplace would not come on. A last ditch effort was to get a new can of air, with the little straw that lets you direct the air. I place the straw right into the two little holes on both sides of the pilot, and blew them out.Next I blew out all of the holesin the burner, just in case there was a spider nest. Lastly, I cleaned my tp terminals. The resulting pilot light now looks more like an F-14 in zone 5 afterburner, shooting straight out, not out and up, and I could hear little crackles like whatever had been blocking it were burning up now. And when I turned the knob to on, I could hear the gas valve open. So it works for another year!

[hrhofmann]

The pilot light flame must hit the thermocouple correctly, or the voltage t he thermocouple generates may not be enough to operate the main gas valve, while it is enough to keep the pilot light lit. Try adjusting the pilot li ght so that it more directly hits the thermocouple, check for clogged holes in the gas supply for the pilot as the previous poster found to be his pro blem.

[Tony Hwang]

Hi, Main valve is controlled by 24V control voltage, not by thermocouple. thermocouple's job is to keep the pilot on.

[BobinDurham]

Maybe a thermocouple's....but a thermopile generates the energy to open the gas valve. Once you turn the valve to pilot and ignite it, the pilot is on. If the pilot blows out for some reason, the thermopile senses the loss of heat and shuts the pilot valve down. Which is why if you turn the pilot on, push the knob in and ignite it....and you don't let the thermopile heat up enough? The pilot goes out.

[greg]

Thanks for the advice. The paperclip trick worked for me, so I know its not the gas valve. I then disconnected the wall switch and connected the wires, it did not light.

So I assume from this the problem is the wiring between the switch and the unit? That is a major bummer if true as all of this wiring is in the walls and seems to be nailed to the studs as I can't pull it loose.

Open to any suggestions.

[greg]

Paperclip test worked.

Put a meter between the two screws that were successful in the paperclip test and reading was 260.

Any advice is appreciated from here. I tried to just manually connect the two wires that were at the wall switch and that did not work.

[Tony Hwang]

Hi, If the FP has removable sealed glass front, there is a interlock switch. Just like gas furnace has cover interlock switch. Checked that switch?

[Tony Hwang]

Hi,

260 what? Volt DC, AC? Or Ohm reading?

[Stormin Mormon]

I worked on a natural gas fireplace, last year. The HO kept insisting that I had to change the batteries. This made no sense to me. I finally found a plastic box under the FP which had four AA cell. Change the batteries, and it came back to life.

[Terry Coombs]

Probably millivolts , since the OP mentioned a thermopile . I have a customer down in Memphis that is having the same type of problem with a floor furnace , but intermittent . He has whole-house forced air too so he's not cold , but he leaves a crawl space door open a little so his cat can shelter there . He worries about his pipes ...

[greg]

no sealed glass front on this one. Its a normal box with a flu that I open/close.

[greg]

millivolts. It was 220 this morning. Tested the TP terminals. From what I am gathering this means I need a new thermopile?