Posting a message to the forum will remove the above advertisement
  1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.
  2. Checkout our Plumbers Insurance area - heavily discounted Public Liability Insurance and Van Insurance specifically designed for plumbers.

Discuss Losing pressure on a new worcester boiler, but there have been times it has been (temporarily) fixed in the Central Heating Forum area at UKPlumbersForums.co.uk.

  1. James Sellers

    James Sellers New Member

    Hi,
    I would love to get some expert thoughts on my pressure loss problem.
    I have just replaced my boiler and radiators to fix a raft of problems with the heating system mostly caused by old radiators filled with sludge. Unfortunately the loss of pressure hasn't been fixed.
    There are no signs of leaks any where and most of the house is over a studio flat in the basement, so we would be likely to see signs of leaks in our ceilings or in the flat below.
    At the moment I have to refill the system every 1 to 2 days. However there have been a couple of circumstances that seem to have fixed the problem for a couple of weeks, which makes me wonder if it is a leak.
    The first was when the water board decided to change my meter - this was when the old boiler was still in place. After they had finished our water supply was shot. Pressure was down. Toilet flushes would endlessly refill etc. It seems that dirt got into the system, so they sent a contractor out with a compressor to clear the dirt out of the system. This not only cleared the problem but for about two weeks the pressure gauge sat happily on the same bar, before slowly over about a week starting to lose pressure increasingly quickly until I was back to topping up the old boiler at least once a day. One engineer said it must have been coincidence, but I don't really buy that. I am sure that that process did something to stop the problem for a bit.
    A similar thing happened after the new install. I thought everything was great for the first week. The second week was still okish but I started to see a slight drop in pressure, now after 3-4 weeks I am back to topping up regularly, though it is still a bit better than the old boiler.
    The other thing I notice is that when I turn on the kitchen tap which is right by the boiler I can often see the pressure drop quite noticeably - about 1/4 bar. When I turn the tap of the pressure does go back up a bit but usually not to where it was. The tap does have a bit of a drip. I understand that taps shouldn't effect the pressure but that is what I see pretty much every time I run the tap.
    Obviously I will go back to my installers and maybe to Worcester, but both have had a look at it in the past, so I thought I would though it open to the web to see if anyone had any advice.
    All suggestions would be gratefully received.
    Thank you,
    James
     
  2. Rob Foster

    Rob Foster Top Contributor!!

    If your filling loop is passing a bit this would cause the drop. Look at MFD from Flowflex it is a solution. Rob Foster aka centralheatking
     
    • Disagree Disagree x 1
  3. Craig Watson

    Craig Watson Plumber GSR Top Contributor!!

    If his filling loop was passing surely he would have the opposite issue of his pressure constantly increasing as the mains water would over power that of the heating system.
     
    • Agree Agree x 3
    • Funny Funny x 1
  4. Craig Watson

    Craig Watson Plumber GSR Top Contributor!!

    The water board changing your meter and flushing the pipes out would have had no effect on your heating system as they are 2 separate systems so was purely coincidental. The gauge moving when you operate a tap is likely just vibrations though the pipe causing the needle to move because again they are separate systems so should have no impact on the pressure within your heating.

    When do you notice the most amount of pressure loss? You may find when the heating isn't on you may lose more pressure and when the heating is on and everything expands the leak is plugging itself and allowing any wet patches to dry up. Also the size of your system may be making it harder to spot, if your system is small it won't take that much water loss to actually drop the pressure so you may think your looking for a bigger leak than you have.
    You could try thermal imaging, get everything nice and hot and then starting at the boiler you'll be able to trace where your heating runs are which will show up as 2 orange lines, if you see an orange pool then this would indicate a leak.
     
  5. Rob Foster

    Rob Foster Top Contributor!!

    No, op states when tap turned on adjacent to boiler the pressure drops and then reverts. The whole system is obviously at low pressure anyway. I would disconnect filling loop and see if the pressure changes, if will probably go down over time as there is a leak but not vary in a short time ..centralheatking
     
  6. king of pipes

    king of pipes Trusted Plumber GSR

    If your losing pressure then you have a leak somewhere a dripping tap won't make a difference to the heating a hot dripping tap could be a nuisance, we would only be guessing where the problem is check all your radiator valves and obvious joints . Kop
     
  7. James Sellers

    James Sellers New Member

    Thanks for you replies.
    I would say that the system loses pressure faster when the heating is off. Though it doesn't appear to be clear cut.
    With the old boiler however I think the pressure dropped slowest if I turned the boiler of completely by pulling the plug out.
    As for the water board action and the temporary fix being a coincidence, as I said, I find that hard to believe, The system had lost pressure consistently for about 3 years maybe longer as that is when we moved in. Then suddenly we have taken these measures and suddenly everything works fine for a bit. I think something happened. Presumably the two systems meet somewhere, Could that valve or whatever it may be be the problem.
    I shall certainly share your thoughts with the installers.
    Any suggestions how to go about getting the thermal imaging done? Is it something you would expect the intallation company to do, or is it usually a specialist thing?
    Thanks again.
     
  8. Riley

    Riley S. Mod Trusted Plumber GSR Top Contributor!!

    Get away from the water board works. It is coincidence.
     
    • Agree Agree x 1
  9. James Sellers

    James Sellers New Member

    Haha. Alright, I will try. Thanks.
     
  10. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    Pump starting and pump stopping
     
    • Like Like x 2
  11. Stigster

    Stigster Plumber

    Maybe the PRV is letting by sometimes? Could be an expansion vessel undersized or failing issue. Cut the finger off a rubber glove and attach it to the end of the D2 discharge (Blow off/Pressure relief pipe) with a rubber band. If that is where the water is escaping you'll be able to tell.
     
  12. Craig Watson

    Craig Watson Plumber GSR Top Contributor!!

    Doubtful, he had pressure loss on the old system before the new one was fitted and it's unlikely the expansion is undsized on a studio flat.
     
  13. Stigster

    Stigster Plumber

    Fair enough but it is an easy thing to eliminate and doesn't cost anything to investigate. Still worth a look I'd say.
     
  14. macrut125

    macrut125 New Member

    I had similar problem....added Miracle Seal and problem fixed...
     
  15. Riley

    Riley S. Mod Trusted Plumber GSR Top Contributor!!

    But last resort, sealing solutions can block air vents and similar within the boiler
     
Loading...
Similar Threads - Losing pressure worcester Forum Date
Worcester Bosch Greenstar 28i LOSING PRESSURE Central Heating Forum Apr 11, 2019
WB HEATSLAVE 18 25 losing pressure Central Heating Forum May 23, 2019

Users found this page by searching for:

  1. combi boiler forum uk

    ,
  2. new boiler losing pressure

Users found this page by searching for:

  1. combi boiler forum uk

    ,
  2. new boiler losing pressure