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What is a 24V Thermostat

h12721aa Member Posts: 17
I am setting up a Burnham Boiler MPO-IQ 84000. On the  electrical hook Print , it says 24v thermostat by

others . I understand this to be the existing thermostat in the Rooms. The

question is, will the old 24 V transformer from the old boiler still be used ?

What is a 24V Thermostat? Should it deliver 24V or is it

rated for 24V?



  • Ironman
    Ironman Member Posts: 7,336
    24v stat...

    That means it operates on 24v system. The stat doesn't produce any power, the transformer does that.

    There are numerous ways the system can be wired depending upon the components used and the control setup.

    Given the nature of your question, it's obvious you're attempting something well beyond your knowledge and expertise. Please, call a pro who knows control work before you fry something expensive or cause a fire or safety issue. This is NOT something that someone will be able to talk you through.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • h12721aa
    h12721aa Member Posts: 17
    edited September 2014

    The old boiler had an external 24V Transformer.

    Will this on require the same set-up?

    Will 24V to be put in to the 

    T T terminal by external transformer, or do they  needs to be closed by the thermostat switch

    and no external transformer is used?

  • icesailor
    icesailor Member Posts: 7,265
    Low Information:

    If you have to ask that question because you do not know the answer, you need professional help.

    Like Ironman said.

    You might cause injury to yourself and others. Hire a pro.

    Would you ask a Gynecologist for an opinion about your prostate? 
  • Paul48
    Paul48 Member Posts: 4,469

                As a DIYer, these things should have been sorted out before the boiler came in the house. You needed to read,and understand every aspect of the I&O manual for that particular boiler.Your questions should have started here, months ago.Even with proper guidance from the pros here, you cannot properly set up the burner for that boiler. You would still have to have a pro come in with a digital combustion analyzer to set it up.

               This is not on the same level as pulling an engine out of a car, using a rope over a tree branch. Treat it as though it requires schooling, apprenticeship, and years of experience, because the alternative is, you can kill people.