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Furnace help

Jsmith94Jsmith94 Member Posts: 12
edited October 2019 in Gas Heating
I’m trying to purge my system but it’s not pushing the water out. What can I do? 1960s crane furnance. 1 zone going from basement to second floor.different heating for first floor.


  • Jsmith94Jsmith94 Member Posts: 12
    My grandfather hasn’t let me get rid of the mess down here don’t mind it 🤣
  • Intplm.Intplm. Member Posts: 1,129
    Is the water on ? Your PRV is up and in the run position. Check to make sure the valve serving the prv is open all the way.

    What's the pressure reading on your boiler ?

    Your purge point is about three feet above the circulator.

    Have you done this before or is this your first time?

  • Jsmith94Jsmith94 Member Posts: 12
    edited October 2019

    This is my first time I just put on a new pressure relief valve because the old one was dripping
  • Jsmith94Jsmith94 Member Posts: 12
    Hot water leaving furnance but it doesn’t make its way back. When I try to purge a lot comes out at first then dies out to a very light stream
  • Jsmith94Jsmith94 Member Posts: 12
  • HVACNUTHVACNUT Member Posts: 3,265
    edited October 2019
    Where are you purging from?
    The 2 valves above the circulator is where you need to purge.
    Shut off the boiler.
    Shut off the valve to the expansion tank.
    Shut off the valve above the circulator.
    Connect a hose to the drain valve directly above it.
    Open the drain valve and purge the system of air. Don't fast fill. Put the lever down and let it purge for a good 10 minutes.
    Shut the drain valve.
    Drain the expansion tank. (Which is probably why the relief valve was leaking.)
    Open the valve to the expansion tank and check system pressure. 12-15 psi.
    Open the valve above the circulator.
    Crank up the heat.
    Start, cycle, and check.
    Keep an eye on the pressure until the boiler makes limit temperature. 12- 20 psi.
    Is this a monoflo system? Do the convectors have bleeders?
  • DZoroDZoro Member Posts: 1,035
    What expansion tank do you have?
  • ChrisJChrisJ Member Posts: 10,850
    Side issue but, do barometric dampers work pointing down?
    I know the answer, but that's what it looks like I see in the picture.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • HVACNUTHVACNUT Member Posts: 3,265
    > @ChrisJ said:
    > Side issue but, do barometric dampers work pointing down?
    > I know the answer, but that's what it looks like I see in the picture.

    Is this a trick question? No, a barometric damper can't work pointing down. But that's not a damper. Dont know why it was done here without a proper draft regulator. That's an old timey way of drafting gas boilers and water heaters. The bull was oval on the old tee's.
    And no Kentucky Fried Sparrows in the breach. They were able to fly free another day.
  • Jsmith94Jsmith94 Member Posts: 12
    I figured it out when I changed out my pressure relief valve.there was no shut off going out of the boiler so when I drained the water to change PRV it put a lot of air in system. I shut off the valve above the circulator and then connected hose to drain valve but hardly nothing would come out. So I tried to use the regulator for fast fill but it wasn’t after spending hours scratching my head,reading forums and draining expansion tank. Then I unscrewed the cap for regulator and pressed the pin real hard hoping for the best and I could hear the water filling fast, finally I can hear the water moving. It must of had a buildup of gunk . Then it pushed through the system and came out the faucet above the circulator. Now I got heat :smiley: thanks for the help
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