Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.

0.5psi on the pressuretrol, Guage reading over 2

Options
Probably not right, right?

Comments

  • Paul_11
    Paul_11 Member Posts: 210
    Options
    Pressurtrols are not very accurate.
    Rarely I have never seen a pressuretrol that would turn off a boiler below 3 psi
    Since 1990, I have made steam systems quiet, comfortable, and efficient. We provide comfort while saving the planet.
    NYC RETROFIT ACCELERATOR QUALIFIED SERVICE PROVIDER

    A REAL GOOD PLUMBER, INC
    NYC LMP: 1307
    O:212-505-1837
    M:917-939-0593
  • Jamie Hall
    Jamie Hall Member Posts: 23,319
    Options
    Well, one of them isn't... question is, which one? Are the pigtails clear? What does the gauge read when the boiler is cold? Is it the 30 pound gauge?
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • Fred
    Fred Member Posts: 8,542
    Options
    It may be right. The .5PSI on the front of the Pressuretrol is the Cut-in (the amount of pressure (or below) where the Pressuretrol will allow the burner to kick on if the thermostat calls for heat or in the case the boiler pressure reaches the Cut-out Pressure, the Pressuretrol will keep the burner off until the pressure drops down to .5PSI.
    Inside your Pressuretrol, there is another white wheel on the floor of the unit that is the Differential. If that is set at 1PSI or 1.5PSI and the Pressuretrol is additive (it will say "Additive inside the unit) then the Cut-out will be 1.5PSI to 2PSI (They aren't 100% accurate but close enough) and the gauge may/should read about 2PSI. Was the boiler running an extended period of time or recovering from a set-back? It takes a while to build 2PSI of pressure if there is good venting on the Mains and the boiler is properly sized for the radiator EDR.
  • bvaughn76
    bvaughn76 Member Posts: 54
    Options
    Learning something new everyday. The pressuretrol was set for a differential of 2psi. So theoretically it was fine running at that pressure. My boiler installer was out yesterday working on the issues in my other post and we checked out the pressuretrol. I think for his sanity and to avoid me having doubts about it put a new one on. We set the differential for 1psi.

    Any logic behind how to select your differential? I assume if my system is running smooth and don't need more than 1psi of steam, setting the pressuretrol for 0.5 with a differential of 1, should keep it in that 1psi range.
  • Fred
    Fred Member Posts: 8,542
    Options
    bvaughn76 said:

    Learning something new everyday. The pressuretrol was set for a differential of 2psi. So theoretically it was fine running at that pressure. My boiler installer was out yesterday working on the issues in my other post and we checked out the pressuretrol. I think for his sanity and to avoid me having doubts about it put a new one on. We set the differential for 1psi.

    Any logic behind how to select your differential? I assume if my system is running smooth and don't need more than 1psi of steam, setting the pressuretrol for 0.5 with a differential of 1, should keep it in that 1psi range.

    The max pressure you want to run at is about 1.5PSI, hense the reason for setting the Cut-in at .5PSI and the Differential at 1PSI for a Cut-out of 1.5PSI. If you have adequate Main Vents and the boiler is properly sized for the Radiator EDR, you really will only trip the Pressuretrol Cut-out on very cold days and when trying to recover from a deep set-back. All other times the pressure should stay below that 1.5 range. (You do have an Additive Pressuretrol (Gray unit with 1 Cut-in scale on front and white differential wheel inside). The Subtractive Pressuretrol has 2 scales on the face, a "Main" and a "Differential" scale.