Thermopile Ignition System Replacement, Please ?

Old 09-26-21, 06:02 AM
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Thermopile Ignition System Replacement, Please ?


Great Forums here, and folks. Am in my mid 80's now (wow), so please put up with me a bit.

Would be most appreciative for some very specific suggestions, and opinions, regarding the following:

Live in a typical Colonial in New England that has a natural gas, forced hot water, heating system.

About 35 years old, but would love to get one more season out of it.

It has a Thermopile ignition system for the furnace, which apparently nobody offers anymore. Have really beaten the bushes over this, but it seems that nobody mfg’s that style these days. All the “big name” installers in the area don’t even know what I’m talking about. Great system for when power is lost; simply run it as a gravity system.

If you know of a good furnace manufacturer that still offers it, (natural gas, forced hot water) please do
let me know here ?

Anyway, my guess is, and it is only a guess, that if it has “problems” over the winter it would very likely be the thermopile assembly. Since none of the installers even know anymore what this is, I thought it might be wise to simply buy an assembly in case it is needed, give it to the installer folks if needed, and have them install it. Should be very simple to do, I would imagine.

Sure can’t expect them to find the proper replacement, quickly, in the dead of winter, especially seeing their un-familiarity with thermopiles. So I thought buying one now might be good insurance.

The present furnace is a Hydrotherm Model HC-145:

Input 145,000 Btu/Hr

Output 116,000

Rating 100,900

a. Could some of you folks who are familiar with this kinda "stuff" please suggest specifically what thermopile
unit to purchase, and from where ?

(is it even possible after all these years, to know what Thermopile Model would be correct for such an
old furnace ?)

b. Should I also purchase a gas valve assembly, or any installer outfit would likely have this component ?
If so, which, please ?

Much thanks, really appreciate the help,


Old 09-26-21, 11:44 AM
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No one stocks millivolt valves.
If you want to get spare parts just get a replacement thermopile.

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