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Correct pressures to run boiler at?

Hi guys,

I picked up a 3psi gauge and dialed my presuretrol to cut out at 1.5 pounds and cut in at .5 pounds. But I wonder if I can tweak the pressures to be more efficient. How do I calculate the exact pressures I should be running at?

I can measure my mains and the length of pipe plus elbows. Which one governs? The longest one? Then, what pressures would be correct?

Thanks in advance...


  • Finding the sweet spot

    Use your gauge, to see the back-pressure of venting, and add main vents until the pressure is a couple of ounces, during the venting phase.

    You probably could heat the house with 2 ounces, unless your boiler is over-sized.--NBC
  • Dsisson
    Dsisson Member Posts: 73
    How do I

    How do I use the gauge to see the back pressure of venting during the venting phase?

    All I see is that the needle sits on zero until it goes up to 1.5, then the boiler kicks off, the needle drops to .5 then the boiler kicks in again. (?)
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