Advertisement
If you have a new account but are having problems posting or verifying your account, please email us on hello@boards.ie for help. Thanks :)
Hello all! Please ensure that you are posting a new thread or question in the appropriate forum. The Feedback forum is overwhelmed with questions that are having to be moved elsewhere. If you need help to verify your account contact hello@boards.ie

Oil Boiler Pressure dropping

Options
  • 17-09-2019 11:02am
    #1
    AstraMonti
    Registered Users Posts: 5,718 ✭✭✭


    Hi guys,

    Would there be another reason -apart from having a leak somewhere in the system - that the oil boiler pressure drops and needs often topping up?
    When the system is full, pressure is about 0.7 and when it's working it's about 1.5. If you leave it for a couple of days pressure drops to around 0.3. All rads are heating up fine.

    Many thanks.


Comments

  • Options
    #2
    Wearb
    Moderators, Home & Garden Moderators Posts: 6,231 Mod ✭✭✭✭Wearb


    On the face of it that seems normal. The difference between 0.7 and 0.3 might be accounted for by the difference in being off for 1 day and being off for a couple of days. Put it to 1 bar when its at 0.7 and see if it still drops to 0.3 after a few days. But I suppose the fact that it often needs topping up does point to a leak or paragraph below.

    Anyway to answer your question; the pressure relief valve could be letting by or radiator valve spindles etc.

    Please follow site and charter rules. "Resistance is futile"



  • Options
    #3
    AstraMonti
    Registered Users Posts: 5,718 ✭✭✭AstraMonti


    Thank you. Apart from seeing a wet spot on the wall/floor, is there a DIY way of finding leaks?


  • Options
    #4
    AstraMonti
    Registered Users Posts: 5,718 ✭✭✭AstraMonti


    So I filled the system yesterday. I just got back home and I just saw this thing in the picture dump a large amount of water to the drain behind the wall. Why would it do this?

    OTf1uw9.png

    Pressure is now 0.
    Anyone to shed some light please?


  • Options
    #5
    K.Flyer
    Registered Users Posts: 8,565 ✭✭✭K.Flyer


    That's a condensate trap which is meant to dispose of condensated water from the boiler and has no bearing on water pressure.
    Water would normally only pass through it when the boiler is running or very shortly after it has stopped.
    Top up the pressure again but do not run the boiler for 24 hrs and see if you can detect a trickle of water through the pipe from the trap during that time.


  • Options
    #6
    AstraMonti
    Registered Users Posts: 5,718 ✭✭✭AstraMonti


    Thanks very much. The boiler had just started working when it start dumping the water. I can't quantify the amount, but it was a full blown stream of water going for a solid 30seconds.


  • Advertisement
  • Options
    #7
    Tom44
    Registered Users Posts: 948 ✭✭✭Tom44


    Pressure doubling from from cold to hot .7 bar to 1.5 bar is not normal and indicates a flat pressure vessel in my book.
    Pressure should only go up by 25%


  • Options
    #8
    Dtp1979
    Registered Users Posts: 12,736 ✭✭✭✭Dtp1979


    If the pressure is repeatedly settling at .3 and not going to 0 then chances are the coil is leaking on the hot water cylinder


  • Options
    #9
    mrblack
    Registered Users Posts: 350 ✭✭mrblack


    AstraMonti wrote:
    Would there be another reason -apart from having a leak somewhere in the system - that the oil boiler pressure drops and needs often topping up? When the system is full, pressure is about 0.7 and when it's working it's about 1.5. If you leave it for a couple of days pressure drops to around 0.3. All rads are heating up fine.

    Dtp1979 wrote:
    If the pressure is repeatedly settling at .3 and not going to 0 then chances are the coil is leaking on the hot water cylinder


    Test the expansion vessel for leaks. I had a similar pressure dropping problem for ages and found water coming out the valve when I tested it. Changed it myself and now pressure is stable again.


  • Options
    #10
    AstraMonti
    Registered Users Posts: 5,718 ✭✭✭AstraMonti


    mrblack wrote: »
    Test the expansion vessel for leaks. I had a similar pressure dropping problem for ages and found water coming out the valve when I tested it. Changed it myself and now pressure is stable again.

    Is it a DIY job?


  • Options
    #11
    AstraMonti
    Registered Users Posts: 5,718 ✭✭✭AstraMonti


    Dtp1979 wrote: »
    If the pressure is repeatedly settling at .3 and not going to 0 then chances are the coil is leaking on the hot water cylinder

    Thanks, the cylinder is 3months old, had the problem before installing it too.


  • Advertisement
Advertisement