Low gas pressure at Fireplace

[JStash]

I’m a bit stumped. I have a gas fireplace, it’s probably 10-15 years old. I’ve used it the last 3 winters with no issue. Hold on the pilot, light it with the sparker, wait a minute. Pilot stays on, turn on the switch and it fires up.

This year I couldn’t get it going. Long story short I’ll light the pilot, but it won’t stay lit. The pilot slowly dwindles and goes out within 5 second of lighting it and holding in the pilot. At this point, I can’t light it again for an hour or so, but the issue repeats. I pulled off the glass to confirm the pressure actually dwindles down to nothing while the pilot is held in.

So it’s like I have low pressure/blockage, but had no issues last year. All my other gas appliances are running just fine.

Do gas fireplace valves fail in this fashion? Or is the issue upstream of the appliance?

I’m having a hard time getting someone to come look at it, which is why I’m posting on here.

Thanks

 

[DAKSY]

You need to tell us the manufacturer & model number of the unit, but I bet the thermocouple is failing & needs replacing.

 

[JStash]

You need to tell us the manufacturer & model number of the unit, but I bet the thermocouple is failing & needs replacing.

Montigo C34-DV

Would the thermo couple effect gas going through the pilot while I'm holding the pilot in? I thought it was just for when you release the pilot, the heat on the thermo couple keeps the gas flowing?

 

[DAKSY]

I probably should have read your post a little better. I missed the gas pressure drop. Have you used a manometer to check the actual pressure? If you have good pressure at the valve, you may have some debris in the pilot tube. Try pulling the pilot tube from the valve & blowing air thru it from the pilot orifice end.

 

[JStash]

I probably should have read your post a little better. I missed the gas pressure drop. Have you used a manometer to check the actual pressure? If you have good pressure at the valve, you may have some debris in the pilot tube. Try pulling the pilot tube from the valve & blowing air thru it from the pilot orifice end.

I've not used a manometer. That'll probably be my next step. I actually just realized I have a second pipe coming directly off the gas meter outside my house, which has it's own regulator. Gunna valve it off and see if I can still replicate the issue. If that completely stops the flow of gas, maybe this other regulator is the issue. Due to the layout of my house, it actually would make sense this other separately regulated pipe might go to the fireplace.

As for the pilot valve, I heated the thermo couple with a torch and tried turning my fireplace gas valve to "On" to see weather it's an issue with the pilot. I heard it click - I think, but no change, still no gas.

 

[Millbilly]

I would start with taking apart and cleaning the pilot assembly.