DIY Home Improvement Forum banner

Pilot light wont stay lit...Circuit problems?

1549 Views 3 Replies 4 Participants Last post by  oncall
Hello everyone,

I am working on a ventless gas stove in my living room. We have had it for about a decade now and it works great! Well worked great.

Last year it stopped working because the pilot light assembly wouldn't stay lit. I replaced the thermocouple and the pilot assembly (I had no choice)

It fired right up and ran fine for another year. It has ran for about a month so far this winter but the pilot light has gone out on me twice. It was pretty stubborn to get lit again but I always managed to light it. This time, she's not coming back on. Here are a few more specifics

To light
_Press and hold, If you hold all the way down the electronic sparker lights the pilot. This unit works fine and consistently sparks over and over.

You have to hold the button down for a minute until the thermocouple warms up then you let go of the button and the pilot light should stay lit. Mine does not. I assume it's the thermocouple acting up again. I grabbed my DMM and measured the voltage difference between the two unplugged thermocouple wires (I unplugged them to measure) It starts at 0 and raises consistently to .5~.6 volts in about a minute. I don't have a wiring diagram but this seems to me like this thermocouple is working.

I don't know what I should check next. The pilot if very strong when you hold the button down to light it manually so I don't think we have a problem with the gas lines or anything like that. The electronic system isn't sensing the thermocouple right and it's shutting off the valve once I let go of the button for the pilot. The connections are all very very clean so corrosion is a non issue. I'm almost stumped.

It's a Monnesen stove, like this model.,r:10,s:0,i:118

Thanks for the help! Sorry for such a detailed description I don't think I could accurately describe the issue without being so descriptive.
1 - 1 of 4 Posts
If the stove is the same as the one in the link ...then you have a milivolt powerpile, not a thermocouple. When you said you measured the voltage from the two wires that confirmed it. Anyway, I assume you got the .5 - .6 v with the pilot lit. powerpiles generaly put out ~750 Milivolts (.75 volts). The gas valves idealy like that amount but have been known to operate on as little as 300Mv. yours should operate at 500-600 with no problem. At this time I would suspect a faulty gas valve. Do you have a schematic for this unit you could post? When you said this "The electronic system isn't sensing the thermocouple right and it's shutting off the valve once I let go of the button for the pilot" it has me wondering. Normaly the powerpile is hooked up directly to the gas valve. One wire to the TP terminal and the other to the TP/TH terminal which then routs power thru the other safety devices and the thermostat (if equipped) and back th the TH terminal
1 - 1 of 4 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.