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Air in Boiler pipes.

Burgh60 Member Posts: 4
Boiler was running fine. It was off and I turned it back on Friday night. I noticed Saturday morning it was a little chilly. I check and some of the radiators were not hot. I tried bleeding my base board heating pipes and no water is coming out. So I tried hooking a hose up to the valves on the return sideto bleed the air. I belive when I opened the valves on the return side the water came out but it did not repressurize. When I open any of the three valves on the return suide to run water outside they run and then just stop no water. Boiler pump is running fine.Can you hook a water line up to the Boiler main drain valve to force water into the system and push the air out of the valves by opening the valves on the return side one at a time. Thats why I drained outside to purge air but water ended up not running after awhile. Upstairs radiators were hot but after draining it appears their is no water pressure up stairs.

Thanks for your input in adavnce.


    JUGHNE Member Posts: 10,791
    There should be a pressure gauge on the boiler, what is the PSI show?

    There is most likely a cold water fill valve connected to the boiler.
    There would be a water stop valve and then a pressure reducing valve.
    Is the water stop open?

    Pictures are needed.
  • Burgh60
    Burgh60 Member Posts: 4
    Here are some pictures .

  • Burgh60
    Burgh60 Member Posts: 4
    The water feed to the PRV is on. I attempted to check the screen on the PRV but water kept dripping out so I didn't check it as the shutoff valve me not have closed when I shut it off. Also the picture where the hose is connected are 3 retun pipes. If I open to drain air out it will drain water then all of the sudden nothing is coming out. I checked all Rads downstairs and water comes out. The Rads upstairs no water comes out which makes me belive there is no pressure or water up stairs.
    JUGHNE Member Posts: 10,791
    If your pressure gauge is correct at 20 PSI, that should lift water up almost 50'.

    Does the pressure gauge ever move? It may be stuck.
    You can get a pressure gauge with a garden hose adaptor and put it on any hose fitting of the piping to see what you actually have.
    The boiler drain would be best but that valve may not operate very well.

    Your PRV may be stuck and not feeding also.

    Do not run the boiler or pump until you are sure you have water in the system.
    The temp shows about 200 degrees....do not add cold water to that until it cools down.

    You may need a pro to come in.
  • Burgh60
    Burgh60 Member Posts: 4
    The thing is I had heat up stairs and in my den yesterday until i tried to bleed some of the water and air out on the returns. Now I have heat in the den and thas it. The heat has been going to about 180 and leveling off. My pressure gauge was maxed out until I took the cover off and flicked it it seems to be staing at 20 all f the time. It would not suprise me the pressure gauge is bad. Or the PVR valve. System has been running like a champ for 20 years other than bleeding the Rads.
  • leonz
    leonz Member Posts: 840
    Take this advice from a fellow homeowner,

    1. Can you provide us with a picture of the bladder tank and air scoop or 2. the steel compression tank and
    airtrol valve if that is what is used to create the point of no pressure change.

    It would probably be best to let the boiler cool down and drain it to change the gauge with a new american made 4 inch square or round pressure gauge.

    Avoid putting thread sealing tape or sealing paste on the gauge threads it as that will affect the gauges ability to register the temperature.

    I do not see a low water cut off on your boilers plumbing. Is there a tapping on the side of the boiler that will accept a hard wired 3/4" NPT low water cut off to protect the boiler from burning dry???

    Can you show us a picture of the bladder tank and air scoop and the plumbing around them if it uses a bladder tank??

    You need a plumber to upgrade your gas boiler with a low water cut off and better return line plumbing with boiler drains to get the air out of the system.