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Help bleeding system

Hello, recently my boiler has had trouble keeping up with the cold temperatures. I believe there is air in the lines. I have to admit im an electrician by trade so im not so sure about this plumbing stuff. What would be the correct steps for bleeding my system? Thanks in advance for any help.

https://imgur.com/a/wtA5QUA

Comments

  • Wellness
    Wellness Member Posts: 129
    edited February 2020
    It doesn't look like you have any shutoff valves to isolate water in your three zones. Do your radiators have any bleeders on them? The ideal setup would be to have drain cocks above each supply pump and a shufoff valve on the return and then you could force higher pressure water through each zone until the air was out, then, fill up the rest of the system.
  • STEVEusaPA
    STEVEusaPA Member Posts: 5,973
    edited February 2020
    @Wellness Did you look at both pictures?
    This is an easy purge, on a very nice 'pumping away' set up. Shut off power to the circulators and the unit (leave those isolation valves open). Close the valve marked 'Main'. Close the 3 return zone shut off valves (1, 2, 3)
    Hook a hose up to the hose bib drain, run it over to a laundry sink and stick it in a bucket (in the sink), secure with spring clamp.
    Feed and maintain about 20 psi in the boiler while you bleed.
    Open one valve on the return zone, open the drain, maintain feeding and 20 psi, watch bucket fill and overflow, keep going until all bubbles are gone.
    Quickly and simultaneously, close drain, and stop feeding (maintain pressure).
    Close the valve for that zone, repeat for the next 2, one at a time.

    When you're done, open all for ball valves (3 zone, and ball valve on return (main).
    Bleed off a little water, to drop the psi back down to 12 (or wherever you need it.
    Usually after purging the zones, I'll run the circulators for a minute. If it needs more purging, repeat the process.
    The main thing is to never let the pressure drop while purging, which you can accomplish by kinking the hose and watching the gauge.
    As you can see it's harder to explain than to just show you...

    steve
    GrallertSuperTech
  • Grallert
    Grallert Member Posts: 540

    @Wellness Did you look at both pictures?
    This is an easy purge, on a very nice 'pumping away' set up. Shut off power to the circulators and the unit (leave those isolation valves open). Close the valve marked 'Main'. Close the 3 return zone shut off valves (1, 2, 3)
    Hook a hose up to the hose bib drain, run it over to a laundry sink and stick it in a bucket (in the sink), secure with spring clamp.
    Feed and maintain about 20 psi in the boiler while you bleed.
    Open one valve on the return zone, open the drain, maintain feeding and 20 psi, watch bucket fill and overflow, keep going until all bubbles are gone.
    Quickly and simultaneously, close drain, and stop feeding (maintain pressure).
    Close the valve for that zone, repeat for the next 2, one at a time.

    When you're done, open all for ball valves (3 zone, and ball valve on return (main).
    Bleed off a little water, to drop the psi back down to 12 (or wherever you need it.
    Usually after purging the zones, I'll run the circulators for a minute. If it needs more purging, repeat the process.
    The main thing is to never let the pressure drop while purging, which you can accomplish by kinking the hose and watching the gauge.
    As you can see it's harder to explain than to just show you...

    perfectly stated
    STEVEusaPASuperTech
  • STEVEusaPA
    STEVEusaPA Member Posts: 5,973
    Even though I probably haven't read Dan's book in about 10 years, the image of 'firing each zone like a torpedo' (paraphrasing of course) sticks in my head, as good writing always should. <<---Ignore poor sentence structure when giving someone a compliment about good writing ( I mean writing well)! LOL
    steve
  • JeanoBambino
    JeanoBambino Member Posts: 2
    Steve, thanks so much for the very informative reply. I just have a few questions to make sure I don't mess this up. I read somewhere that you can crack the boiler if your running cold water into a hot boiler. Is there any risk of that with this method?

    When you say feed and maintain do you mean just monitor the gauge on the supply? Kinking the hose and slowing the draining water will bring the psi up.

    Shutting off the disconnect switch will kill power to the circ pumps and boiler. That's correct?
  • STEVEusaPA
    STEVEusaPA Member Posts: 5,973
    Yes you don’t want to put cold water into a piping hot boiler.
    You’ll need to find the fast fill lever on the water feed. Otherwise you won’t be able to get the pressure up and maintain it. You’ll only be able to get the pressure up to whatever the feed is set for, probably 12 psi.
    Yes shutting off power is easiest, or turning all thermostats down. Unless your boiler maintains temperature, then a low boiler temperature could cause the boiler to fire.
    steve