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radiant heat?

hey brad it is conventional boiler cga7 so wire w/ boiler aqustat or w/ secondary aquastat


  • radiant heat?

    The primary pump in the primary loop how does it get wired when does it turn on
  • Brad White_25
    Brad White_25 Member Posts: 21
    Depends on a couple of things

    If a condensing boiler and hence tolerant of colder temperatures, I tend to favor constant circulation based on outside air temperature (65F and below the circulator runs).

    The other way is in parallel with boiler firing, the argument being that there is no point in circulating what is not being heated. Personally I favor constant for simplicity, full purging/use of boiler heat and freeze protection (except in power outages of course).

    In cast iron/conventional, the circulator would start based on boiler temperature but with a bypass valve to the return to avoid shock and condensation.

    There are other philosphies I am sure.

    Secondary strategies also abound. Again, there I favor constant circulation also, with injection or valve control.
  • radiant heat?

    wire w/ boiler aquastat or secondary aqustat
  • Brad White_25
    Brad White_25 Member Posts: 21
    Boiler aquastat

    in that you are trying to protect the boiler.
    Do you have return water protection (mixing valve or bypass valve to elevate HWR temperature)?

    Old school method said to start the pump only after the boiler reached 130 to 150 F. Trouble could occur with that first slug of cold water to a hot boiler, so tempering the HWR was developed.
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