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Boiler won't fire unless......

Portgas Member Posts: 8
I have a 35 year old Utica PEG-187S steam boiler running on a millivolt system. The gas control consists of a Honeywell

VS820 with powerpile.

My boiler will not fire up unless I momentarily short the two wires going to the TH terminals on the gas control.

Once the boiler runs, it turns off on its own when the programmed temperature setting is reached.

The pilot light works. I checked all the wiring and the low water cutoff switch.

It was suggested in the Steam Forum that the problem may be with the powerpile and that I post it here.

Can this be confirmed or can anyone suggest what may be causing this problem?


  • Ironman
    Ironman Member Posts: 7,106
    edited January 2013

    It could very well be the powerpile generator. We don't recommend that DIY's attempt repairs on gas trains. It requires proper training and equipment.

    I'd recommend that you try the "Find a Contractor" tab above and see if you can find someone in your area that is competent on millivolt systems.

    If you can't locate someone, post back here and ask for us to recommend someone in your area.

    One thing that you can try: on your T'stat, temporarily jumper the "R" or "Rh" terminal to the "W" terminal. If that causes the boiler to fire when it wouldn't before, then you could try replacing the T'stat. Make sure you use one that is millivolt compatible. But, you may still need a new PowerPile generator. Its output has to be checked with a DMM.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
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