Main burner won't light

[demulsion]

A friend of mine is having trouble with their Wolf GDI-30N insert, and asked me to help since I am more mechanically inclined.

The pilot stays lit, and has a proper flame pattern, but the main burner will no longer light at all (they said it used to light after 10-20 seconds).

I've cleaned the thermopile, and get a reading of 730 volts.
I tested the main valve, and am getting 2.3ohms.
Both of those readings are within spec.

There is no wall switch.

Could the on/off/adjustment dial on the main control valve be bad, and can they be replaced separately from the whole valve? Any thoughts or advice would be appreciated.

 

[pageyjim]

Clean thermopile and thermopile connections and make sure they are snug. Is there a thermostat? Is there a limit switch that is tripped? That reading of 750MV DC was with the valve OFF I assume. What does it read with the valve set to on? I imagine it has a limit switch of some kind check that. If it has a thermostat jump the wires at the thermostat to test the thermostat. If it has a thermostat follow the wires to the valve and jump it there to test those wires. If there is no thermostat put a jumper where one would be attached to the gas valve. Lightly tap the gas valve with a screwdriver to see if the valve is sticking.

 

[McGoo_365]

Are you getting gas to the burner? If not take the logs and the burner out and make sure you don't have a blockage in the air shutter. I often find bugs in the air shutters on Napoleon products as they sit vertically in both models. I found one I needed to use a screwdriver to take the dead bugs out. Also take a deep socket ratchet and take out the main gas valve orfice while you have it apart. Hold it up to the light and make sure it's clear.

Sent from my SM-G930W8 using Tapatalk

 

[demulsion]

The 730mv reading was after cleaning the Thermopile. And I'm not certain, but I believe that was with the valve on as well.
There is a thermostat, so I can try jumping those wires.
McGoo_365 how would you recommend testing if I'm getting gas to the main burner? In my mind if there's gas there, the pilot should ignite it. So either the main valve isn't getting the signal to send gas, or the gas isn't making all the way there. And I'm here trying to learn how to determine which it is.

 

[DAKSY]

If you are getting 730mV after the burner is on, then there is an issue.
The mV should drop by about 200mV when the switch is thrown.
You will hear a "click" from the valve when the electromagnets open to
allow the gas to flow.
Turn the pilot down to about 550mV & see what happens.

 

[demulsion]

Okay, gas line is all clear. I put a jumper wire on the TH terminals on the valve, and the gas valve clicked and we had a fire again.

My local fireplace shops tell me they don't carry parts for a Wolf. Also, since the only control for the fireplace was behind the panel at the bottom of the unit, I'm thinking about getting a universal remote control thermostat. Are there any issues I should be aware of before going that route?

 

[pageyjim]

Actually you may not know if it is the thermostat yet. To test the thermostat jump it at the thermostat. If it doesn't light it may be the wiring or a limit switch etc..