Furnace quit on Monday evening. I took my time to investigate because there are lots of other things going on. It is an old Ducane horizontal furnace in the attic with a Honeywell controller (ST912GC, maybe) Fan Timer and SV95D1 Smartvalve,

After a call for heat, the combustion blower spins up and the furnace apparently ignites normally, but the circulating blower never engages. After a relatively short time, everything shuts off and I get no AC step-down volts at the terminal strip. After quite a long time, apparently it resets and can co through it again. The blower motor spins freely. The safety switch on the blower access door seems to be working, opens and closes.

Where do I go from here, check the motor capacitor, trouble-shoot the control board? I don't have a meter with a capacitor check, but I suppose I could buy one. Is there anything that I am overlooking that is easy to check?

That is the end of the furnace problem description. Thanks for reading. What follows is why I am not panicked to fix it.

Thanks for looking

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Don't send too much sympathy my way. Yes, It is cold in S. Louisiana, but I have mini-split heat pumps. I think I was a little below the design temp Monday evening and it got a little chilly in the house with the compressors spinning very fast indeed. At the time of installation, gas was relatively expensive, but price dropped very quickly after the first half winter with them so we went back to using the furnace and ducts for heat for the most part. Part of that is cost and part comfort and convenience. At the time, the controls for the Mitsu mini splits could not do a set-back, only on-off. I like to sleep cool, but have it warm when my feet hit the floor so that does not work.

Ironically, I was thinking that it might be time to recalculate cost to heat with the heat pumps vs. furnace :-) No matter how that looks, I'd probably fix the furnace if it does not cost much. I can get power to it and run it with a portable genset rather than run all the heat pumps and there is still the (lack of) set-back thing.

Again, thanks