Worcester bosch Greenstar 37cdi losing pressure Sanity check

Discussion in 'Plumbing and Central Heating' started by Cluelesstotally, 11 Jan 2015.

  1. Cluelesstotally

    Cluelesstotally

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    Hi all,

    Over the last couple of days my Worcester bosch Greenstar 37cdi has been losing a lot of pressure. I have been topping it up during the day but it loses all pressure over night.

    I searched through previous posts on here and have checked the following as a result.

    - No leaks from visible joints and no wet stains on walls/ceilings, but not checked under ground floor which is a suspended floor.

    - No sign of water from the Prv overflow outlet.

    - Last night I turned off the CH Flow and CH Return valves and turned off the boiler too. Overnight the pressure on the gauge dropped from 1.5 to 1 bar (but not to 0 as it normally does when running normally). Turning the CH Flow and CH Return valves back on and the boiler back on resulted in no change of pressure, staying at 1 bar. Which I think suggests there isnt a leak in the pipework and the problem is within the boiler, does this sound correct? If so, and given no prv overflow water has been detected does this point to a problem with the expansion vessel, as the heat exchanger won't have been operational with the boiler switched off? Is there any other checks I can do and if it is pointing to the expansion tank now, is there anything I can do or is it a job that has to be done by an approved person?

    Thanks
    Becki
     
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  3. petit_pablo

    petit_pablo

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    Sounds like the heat exchanger has gone.
    If the expansion vessel had failed you would be getting water out of the PRV.

    RGI job to check and replace.
     
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  4. Cluelesstotally

    Cluelesstotally

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    Thank you for replying, so a heat exchanger failure would still have an impact on pressure with the boiler switched off?

    Thanks Becki
     
  5. Cluelesstotally

    Cluelesstotally

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    Hi all, further update, last night I repeated the test of turning the CH flow and return valves off and again turned the boiler off with the on/off button on the front but this time I diverted the condenser outlet into a bucket to see if any water came out with the above valves closed and boiler off and found that after about 5 hours the boiler pressure had dropped from 1.5 to 0 bar, 3 litres of water had been collected in the bucket (inside house so no chance of rain adding to it). On turning the CH flow valve back on the gauge jumped from 0 bar to about 0.4 bar, so again suggesting there isn't a leak in the pipework and the problem is in the boiler?

    With this in mind can we can conclude it definitely is the Heat exchanger and if there are more than one can you please confirm which one?

    Finally, is it OK to continue to use the boiler as long as I keep the pressure topped up until I can get someone to fix it?

    Thanks in advance

    Becki
     
  6. Cluelesstotally

    Cluelesstotally

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    Lots of page views but unfortunately not many replies, anyone know?

    Thanks
    Becki
     
  7. denso13

    denso13

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  9. Cluelesstotally

    Cluelesstotally

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    Ok thanks, so:

    - is that the main heat exchanger?

    - is it OK to continue to use topping it up until I can get someone to look at it?

    - does anything else need replacing at the same time or just theeexchanger?

    Thanks
    Becki
     
  10. Cluelesstotally

    Cluelesstotally

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    Ok thanks, so:

    - is that the main heat exchanger?

    - is it OK to continue to use topping it up until I can get someone to look at it?

    - does anything else need replacing at the same time or just theeexchanger?

    Thanks
    Becki
     
  11. picasso

    picasso

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    Yes its the main heat exchanger

    Yes you can keep topping it up and using it till its fixed

    probably just the heat ex.
     
  12. Cluelesstotally

    Cluelesstotally

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    Thank you for the answers much appreciated
     
  13. ServiceNumpty

    ServiceNumpty

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    Ring Worcester Bosch directly, that heat exchanger has a 10year warranty, so should be replaced Free of Charge.
     
  14. DIYnot Local

    DIYnot Local

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    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.

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