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Whining noise and loss of pressure from combi boiler - please help

Discussion in 'Plumbing and Central Heating' started by shays47, 19 May 2017.

  1. shays47

    shays47

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    We have a combi boiler which is approx 9 years old. Recently we have had a lot of problems with it, but thankfully we have boiler cover with British gas, so they have been out to fix it. We have had a new dhw hear exchanger fitted, prv, dhw sensor, and I thought a new diverter valve, but can't see that on the paperwork. It has also been serviced, and they have said it is working at 88% efficiency. Now, it has another fault. The pressure has now dropped to just over 0.5 bar(it was at 1.5 bar after last visit on 9th May). It now makes a whining noise when the hot water is running(the boiler is now set to hot water only, so heating is off). The noise doesn't happen straight away, but after a couple of minutes. I'm no expert, and have looked online, and was wondering if this is a sign of the pressure vessel being on its way out? Any advice would be greatly appreciated.
     
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  3. ianmcd

    ianmcd

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    and the make and model of the boiler is ?
     
  4. shays47

    shays47

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    Biasi Riva compact M96.28SM/C2
     
  5. shays47

    shays47

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    UPDATE ON PROBLEM : I have just put more water into the boiler via the filling loop so the pressure is now at 1.5 bar. I have ran a bath with just hot water, and the boiler has not made the whining noise at all. Any more advice would be fantastic.
     
  6. dilalio

    dilalio

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    Capture the nuisance on video and show BG - they are paid to sort your issues, not be taught by us!
     
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  8. imiller9

    imiller9

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    So, it was low on pressure and noisy. You topped the pressure up and now it's not noisy. Just keep an eye on the pressure over the next few days to see what happens. If the pressure vessel was faulty, the pressure would rise very high and very quickly in heating. Also water would be seen coming out of the pressure relief outlet. Check those next
     
  9. shays47

    shays47

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    Pressure seems fine when the hot water is on. No water dripping from pressure relief valve either. Could it just be due to the age of the boiler and a bit of pressure loss to be expected?
     
  10. Agile

    Agile

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    Pressure loss from leakage if not from boiler PRV vent is likely to be from a slightly leaking valve on the rad system.

    After a boiler has been drained there can be a little air in the system which can take a few days to be ejected and will partly dissolve in the water.

    So it can be quote normal for a small loss of pressure for a few days after maintenance.
     
  11. shays47

    shays47

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    Thank you for the reply. Does 1 bar of loss over approx 10 days seem ok? Also, what would be causing the noise? Is it something to be worried about, or should I just keep topping it up?
     
  12. mcmoby69

    mcmoby69

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    You need to find the leak. If you keep topping it up you will sludge the system up, wreck the boiler and potentially pinhole a radiator.

    I wouldn't expect to top a sealed system up unless work has been done. If a sealed system loses water, it isn't sealed!

    Ask your friends and family for a recommendation.
     
  13. DIYnot Local

    DIYnot Local

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