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24v main gas valve?

Hi All,
I have a peerless steam boiler that uses a 24v main gas valve. There is a 110 to 24v converter to feed the power to it. I recently lost power, just got it back 10 minutes ago actually, and was trying to come up with a way to run my system with the power out. Is the 24v dc? The valve says 24v 60hz 0.3A. I can't find a manufactures label on it to look it up. The 60hz made me think that it is 24vac, but I didn't really think that made much sense. Anyone have experience with these? Also, is it possible to convert that 24v valve to a millivolt valve? So that the system will run without power? There are no additional valves or other powered controls other than the Lwco (which is millivolt or 24dc), there is the high pressure cut as well, but those only cut power, not require power to operate.


  • Abracadabra
    Abracadabra Member Posts: 1,948
    gas valve is most likely 24VAC. I don't think I've ever seen 24VDC gas valves. the "110 to 24v converter" is called a transformer.
    You can most likely run the entire boiler easily using a ~$500 honda inverter which is super quiet and will run for about 8 hours on a single fill.
    JUGHNE Member Posts: 11,021
    There used to be a 24 VAC/12VDC gas valve years ago, however you need the 24 VAC for your LWCO if electronic and you might have a motorized electric flue damper.
    I would go for the generator........running outside of the house....two people died recently with one running inside the house.
  • McSwiggin
    McSwiggin Member Posts: 37
    Thank you for the reply everyone. The LWCO says it works with either 24v or millivolt systems, so I'm not worried about that. I didn't see a damper on my system. Could it be internal to the boiler? I would have thought it would have been external. Thank you again for your help. Generator sounds like it is the way to go, unfortunately. I would have preferred to be able to convert to millivolt, but it is what it is. Thanks!
    JUGHNE Member Posts: 11,021
    Conversion to millivolt requires a pro and a fair amount of parts. The generator may be less money. IMO

  • Abracadabra
    Abracadabra Member Posts: 1,948
    Does the boiler have an automatic water feeder? the LWCO 24V or millivolt is most likely the rating for the switch, not required power for it to operate.
  • Steamhead
    Steamhead Member Posts: 16,715
    With that rating, the LWCO is probably a McDonnell & Miller #67-G.
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
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