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pressuretrol setting question

berm Member Posts: 14
How should a Honeywell PA404A1025 be set?Currently the cut in is all the way down at 0.5 and the dial on the inside is set at 1(the lowest setting).

In the early morning the boiler seems to run up to almost 5PSI and then shuts off and turns back on when the pressure gauge falls to 3PSI. This doesn't make sense to me. Once the system is warmed up the pressure gauge doesn't seem to move at all.

I was thinking of having the pressuretrol replaced with a better model. Any suggestions?


  • BobC
    BobC Member Posts: 5,479
    edited February 2012
    Maybe the gauge

    Those settings are correct for just about any residential steam system. Pressuretrols are not known for their accuracy but it might be the pressure gauge that is telling tall tales.

    As long as the pressuretrol is shutting the system down everything should be safe. The only way to know for sure would be to put a known good pressure gauge on the boiler and see what that reads. rather than replace the existing gauge I would install an auxiliary low pressure gauge so I could see exactly what pressure I was operating at.

    Do you notice a lot of extra hissing from the radiator air vents on the radiators as the pressure gets up there? Are the main air vents on the steam mains working? If the system is really getting up to 5 PSI check the pigtail on the pressuretrol just to make sure it's clear, anything above 2PSI is too high.

    Smith G8-3 with EZ Gas @ 90,000 BTU, Single pipe steam
    Vaporstat with a 12oz cut-out and 4oz cut-in
    3PSI gauge
  • berm
    berm Member Posts: 14

    Thanks for the prompt reply. I removed the pressuretrol to check the pigtail. It is clear. I only get the extra pressure in the morning on a cold start. When the pressure goes up the radiators do make extra hissing noise. The mains are well vented. I have 3 Gorton #1's on antler setup. I still don't understand why it shuts off at 5PSI and comes back on at 3PSI. I thought maybe the pressuretrol was faulty and that's why I am considering replacing it. It seems to be the most basic model so I thought I'd replace it with something better. Not sure what model to choose though. Honeywell has a wide variety. Some people on this forum loke vaporstats others don't. My plumber is not a fan of the vaporstat. He thinks they are too sensitive. I'm open to suggestions...
  • Jamie Hall
    Jamie Hall Member Posts: 23,428
    Either the pressure gauge or the pressuretrol

    is telling lies.  It would be a good idea to find out which.

    As to the vapourstat question -- if you have conventional two pipe or have one pipe, a pressuretrol set as low as it will go -- as you have it (assuming yours is working properly) -- is just fine.  However, if you have any one of the vapour steam systems, it is not sensitive enough to properly control the maximum pressure, and you should use a vapourstat.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • berm
    berm Member Posts: 14
    type of system

    It is a one pipe steam system.
  • berm
    berm Member Posts: 14

    I believe the problem may have been with my pressuretrol.

    I had my 404A replaced with a 404F.

    The boiler now shuts off at 2PSI and turns back on at 0.25PSI.

    I also had a second pressure gauge installed (0-5PSI) in addition to the 0-30PSI gauge.

    This makes reading the lower pressure a lot easier.

    I'll keep an eye on it.
This discussion has been closed.