domestic steam w/ millivolt control

Charles G.

I doubt if anyone is making a steam boiler w/millivolt controls today. And while it COULD be retrofitted by a COMPETENT tech. I doubt if he would nor would the manufacturer stand behind it afterwards. As far as the damper goes, gov't is requiring that of manuf. to achieve efficiency. Good news is they usually self open during power failure. Bad news is they interlock w/existing controls so as NOT to fire the boiler while closed. Can it be done? Yes. Should you consider it? Probably not. Go to Plan B.

Rich Reynolds

Domestic steam w/millivolt control

Hi there,
Maybe someone can answer a few questions for me. I currently have a 1960's era gas-fired Sears steam boiler (one pipe) equipped with a thermopile (millivolt system). The system has worked great, because when we lose power during winter storms, my heating system remains unaffected. Recently I noticed water leaking from the back of the boiler or the return leg (don't know which yet..), and I may have to replace the boiler. My neighbors have had their steam boilers replaced with much smaller Weil-McLain boilers, but they are equipped with electrically operated air dampers. My questions are:

1) Can I equip my new boiler with a millivolt system so the heat stays on when the power is out?

2) Do I have to install this electrically operated air damper? I've never needed it before. If the power goes out, will this air damper prevent the boiler from firing and lead to frozen pipes if I'm not home?

3) I neeed a recommendation for a good steam heat contractor in the Albany-Schenectady-Troy area of New York.

Thanks for any advice you can offer.

-Rich

Unknown

Any boiler purchased

today must have a dual seated gas valve (redundant) as required by code actually an ANSI standard requires it. Millivolt valves are single seated valves therefore cannot be used on modern boilers or furnaces.

If you replace the boiler then the controls on the new boiler must not be changed. In fact in some cases it may void the warranty.