1. Visiting from the US? Why not try DIYnot.US instead? Click here to continue to DIYnot.US.
    Dismiss Notice

Help please, Worcester Bosch greenstar boiler won't keep pressure.

Discussion in 'Plumbing and Central Heating' started by philipbsmith, 24 Dec 2015.

  1. philipbsmith

    philipbsmith

    Joined:
    24 Dec 2015
    Messages:
    4
    Thanks Received:
    0
    Country:
    United Kingdom
    Christmas eve and the boiler has gone on the blink !!

    Started with yesterday morning with a running water noise in the upstairs radiators, so i bleed them and then topped up the pressure on the boiler to 1.3bar
    Ran the heating a bit, turned it of re bleed then topped back up to 1.3bar.

    Few hours later no hot water from the taps and rads not getting hot.
    Went back into the loft and the no pressure at all showing on the gauge.
    Filled it back up, but as you fill it you can hear water trickling through the overflow into the drain pipe.
    It takes 1.5bar of pressure, turn it back on and it makes a few funny noises but seems ok.
    Had a shower, rads getting hot :)
    An hour later no hot water and no pressure at all showing on the boiler gauge.

    I have done this fill, use seems ok, an hour later no hot water routine 3 times now.

    Any idea whats going on, definitely no leaks in the house anywhere, only thing that seems strange is that some water comes out of the overflow pipe when i fill it but not all as it will get to pressure.

    The error code E9 soemtimes come son the boiler but not each time, but my guess is thats just telling me the bliler has tripped as the pressure is to low.

    Thanks
     
  2. Sponsored Links
  3. easyflow

    easyflow

    Joined:
    12 Jan 2008
    Messages:
    472
    Thanks Received:
    60
    Country:
    United Kingdom
    If there,s no leaks pressure relief valve is shot.
     
    • Thanks Thanks x 1
  4. philipbsmith

    philipbsmith

    Joined:
    24 Dec 2015
    Messages:
    4
    Thanks Received:
    0
    Country:
    United Kingdom
    I guessing thats not a 5 minute job to fix?
    Even assuming i can get the bits to repair it with ?
     
  5. easyflow

    easyflow

    Joined:
    12 Jan 2008
    Messages:
    472
    Thanks Received:
    60
    Country:
    United Kingdom
    About 10 mins but you will need the part plus a qualified person to fix.
     
    • Thanks Thanks x 1
  6. philipbsmith

    philipbsmith

    Joined:
    24 Dec 2015
    Messages:
    4
    Thanks Received:
    0
    Country:
    United Kingdom

    10 minutes on christmas eve will probably be about £200 :D

    Thanks for your help, will hopefully be able to nurse it through till monday next week. Its not cold here and we have a log burner that does a good job of heating downstairs. Plus the lads are not to fussed about showering anyway and me and the wife can always share ;)
     
  7. Gasguru

    Gasguru

    Joined:
    9 Sep 2005
    Messages:
    12,119
    Thanks Received:
    3,195
    Location:
    Sussex
    Country:
    United Kingdom
    By bleeding the radiators you have caused the fault code (overheat) and the safety valve to open.

    NEVER EVER EVER bleed radiators on a sealed system boiler setup without checking the expansion vessel for charge pressure.

    The pressure in the vessel is too low (probably flat) and now as a result or removing the air from the rad the expanded water has nowhere to go, hence the PRV opens.

    On the Worcester CDi it is sometimes possible to replace the PRV without pulling the boiler away from the wall or removing the bottom end. On many of the Worcester Greenstars it's a major job. Sometimes, if the system water is clean the valve can be flushed through to clean it.
     
    • Thanks Thanks x 1
  8. philipbsmith

    philipbsmith

    Joined:
    24 Dec 2015
    Messages:
    4
    Thanks Received:
    0
    Country:
    United Kingdom
    Does the PRV blow to save the system, then thats it game over, its done its job and you need a new one. Or can you reset it?

    For next time, are you saying i need to pressurise the system fully to 1.5bar then bleed the rads. Then top it back up to 1.5??

    Thanks
     
  9. Sponsored Links
  10. Gasguru

    Gasguru

    Joined:
    9 Sep 2005
    Messages:
    12,119
    Thanks Received:
    3,195
    Location:
    Sussex
    Country:
    United Kingdom
    Yes the prv stops the system from over pressure. 1 bar is sufficient pressure for a typical property. Don't be tempted to go higher as it leaves little margin. You could pressurise to 2 and open the safety several times to try and flush it through. The real issue is a flat expansion vessel. Since it's inside the casing it's not really diy territory. As it's flat or low on air pressure the expanded water has nowhere to go when you put the heating on and the over pressure operated the prv. Bleeding radiators should never be considered as a diy operation whether you have a sealed system or conventional header tank system....in either case serious damage can be done by the unwary. A little knowledge is a....... and this couldn't be more apt.
     
    • Thanks Thanks x 1
  11. Tay7

    Tay7

    Joined:
    21 Nov 2015
    Messages:
    164
    Thanks Received:
    13
    Country:
    United Kingdom
    Bleeding radiators is not a DIY operation?

    Blooming eck, I better stop refitting bathrooms & installing towel radiators and new showers then in case the world implodes on itself.
     
  12. Gasguru

    Gasguru

    Joined:
    9 Sep 2005
    Messages:
    12,119
    Thanks Received:
    3,195
    Location:
    Sussex
    Country:
    United Kingdom
    For all the problems bleeding radiators causes I would never advise a diyer bleeds radiators. A significant number of plumbers and heating engs should also not bleed them either. So many problems are caused either as a result of an expansion vessel low on charge or flat or a feed an expansion vessel being full of debris. Failure to check these can lead to major failure. Boiler meltdown due to lack of water or worse. One system I attended required a repipe after the owner bleed all the rads. There was no lid on the cistern, loft insulation had been placed on top and due to condensation had filled the vessel. As he bled the rads fibreglass got drawn into the system....but hey ho you know better.
     
  13. Razor900

    Razor900

    Joined:
    16 Nov 2007
    Messages:
    5,455
    Thanks Received:
    2,023
    Location:
    Northamptonshire
    Country:
    United Kingdom
    The OP said it was running into the drain pipe. If he meant the condensate pipe could well be a passing plate
     
  14. petit_pablo

    petit_pablo

    Joined:
    18 Nov 2007
    Messages:
    9,172
    Thanks Received:
    1,861
    Location:
    Lincolnshire
    Country:
    United Kingdom
    It will be a fudged heat cell, rather than a plate if thats the case
     
    • Thanks Thanks x 1
    • Like Like x 1
  15. muggles

    muggles

    Joined:
    28 Oct 2005
    Messages:
    12,943
    Thanks Received:
    2,912
    Location:
    Daventry
    Country:
    United Kingdom
    @philipbsmith Is the water running out of the copper pressure relief pipe to outside or down the white plastic 3/4" condensate pipe and away into drainage? If it's latter, your heat exchanger is goosed. Should be a free repair under warranty provided you've had the boiler serviced every year. If you haven't, you could be looking at £500 or more
     
  16. DIYnot Local

    DIYnot Local

    Joined:
    3 Sep 2019
    Country:
    United Kingdom

    If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

    Select the supplier or trade you require, enter your location to begin your search.


    Are you a trade or supplier? You can create your listing free at DIYnot Local

     
Loading...

Share This Page