Help troubleshoot my furnace

[aunt betty]

It's not getting voltage to the solenoid that opens the gas valve.
That wire burnt off.

I think it's a bad limit switch. This little project is kicking my ass. Plz try and help.

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[aunt betty]

The wire in my hand burned itself loose. I suspect the solenoid went bad from being on too long.
Either that of the limit switch. It's not getting any voltage at all to the blue wires.
I suspect it's 24 Volts dc when it's working right but I'm getting nothing.
Put a new thermostat in...still nothing.

Have reconnected the loose wire and it's not the problem.
Limit switch?

The limit switch is under that panel with the white tape that says caution. There's also a anticipation circuit in there. At least that is what I think it is.

[aunt betty]

Damn. This just got goofy on me. My hvac friend said go check voltage at the thermostat. Spose to be 24 volts AC and I got 11.8. Nothing at the valve. Have a feeling mice are involved in this issue. My silly mom left bowls of nuts all over the place for decoration that got covered up and forgotten. Mice found them. Fuck.

[aunt betty]

That 11.8 reading was milivolts. Doh. Digital meter messes with me sometimes.
No voltage at the thermostat. However I'm finding 24 volts at the transformer and can't find 120 volts anywhere. Something is back-feeding or something. In over my head here.

There has to be 120 feeding the transformer that's making the 24 volts but I can't find it. There are only three wire nuts with little bundles of wires.
Something is burnt up in there.

Tomorrow I got a real HVAC tech coming. I didn't want to use up one of my "favors owed" but it's gonna take that.
Plus I'm leading the poor guy into a hoarded up trash mess. Tried to avoid that. It's embarrasing.
Cross fingers and hope it's something ez and cheap. lol

[aunt betty]

It's done.
The problems.
1. no power. There was a hidden fuse box. Was tracing wires once I found that I had no power. A fuse blew. I feel sorta dumb about that. Digital meter tricked me. Was reading milivolts and my eyes are weak. I should know better.
2. duct work missing? How the hell do you lose an elbow? Hoarded up house eats things but a 7" elbow?

I never should have messed with the thermostat but my hvac guy said you start by checking there.
Taking the old one apart basically broke it so I have to replace that.

Sometimes you have to break stuff to fix it. Aunt Betty

[Deltaman]

Glad it turned out to be a fairly easy fix AB

[aunt betty]

Glad it turned out to be a fairly easy fix AB

If I'd known what I was doing it'd have taken 15 minutes.
Next I found that where the exhaust pipe meets the chimney ...the mortar fell out.
Dealing with a 100-year-old house here.

Next project is "turn the water on". That's going to be an adventure.