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pressure on boiler goes down to zero

Mark Hunt
Mark Hunt Member Posts: 4,909
filling the boiler when the boiler is cold.

Mark H

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  • john_29
    john_29 Member Posts: 6
    pressure in boiler

    had my kitchen redone over the summer and had toe kick heater put in. Also had sliding glass door put in and contractor moved part of baseboard. He left during the summer without filling zone with water. With the coming heating season coming on I filled zone with water. Pressure is at 18 lbs with boiler temperature at 180. I shut feed valve to boiler figuring that it was a closed system as once it was filled with water unless there was a leak somewhere preesure would remain at 18 psi at 180 temp. Boiler pressure goes down to almost zero but I don't see any leaks. I checked relief valve it's dry and all around boiler everthing looks good. How can I find this leak?
  • David Sutton_3
    David Sutton_3 Member Posts: 160
    you said that he drained the sysem??

    If he removed a section of base board he had to have drained the system down, you then said that you filled it, did you purge out all the air??, or just bring it up to 18lbs, if you did not purge it out and just filled it, and tryed to run the system if its pump away it will force the air out and the presure will drop, or there could auto bleaders or return vents and the air releaseing and the presure is dropping , JUst a thought ..David
  • bob young
    bob young Member Posts: 2,177
    loose ends

    ever entertain the thought of calling up the contractor that worked on the system. if he cut into system he is responsible to ensure new equipment works properly but even more important ----restore the system in working order the way it was before he tampered with it. or call a heating outfit and send the contractor the invoice. you paid for a complete job and that is what you are entitled to. nothing less.
  • Rich Jones
    Rich Jones Member Posts: 9

    Any autovents on the system?
  • jim watts
    jim watts Member Posts: 1
    Expansion Tank not pressurized?

    If you have the non bladder type expansion tank this could be the answer. when the older style pressure tank hasn't quite equalized to the system pressure and you shut off the water supply to soon thinking it has, it will slowly go back to zero pressure.Check your tank

This discussion has been closed.