VCW GB 242 EH

Discussion in 'Plumbing and Central Heating' started by Peter GEE, 3 Dec 2021.

  1. Peter GEE

    Peter GEE

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    I have one of these which has worked well for years. Some time ago just about everything except for the pump and heat exchanger was replaced. Today I noticed the boiler needed topping up and I did so to around 1 bar.
    I then found the automatic air vent was dripping. I took it off and tried cleaning the float and crud out. I screwed it back in and repressurised the system.

    It still leaked! I have a new one but note that there is no washer with it and I can see that the old one had a recess specifically for a rubber washer which was inset..
    The new one came with no washer and has no similar recess for such a rubber washer. Should I use PTFE tape instead of a washer or both?
     
    Last edited: 3 Dec 2021
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  3. cross thread

    cross thread

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    Ptfe on the thread will be fine
     
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  4. Peter GEE

    Peter GEE

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    Thank you we will do that. Thanks again.
     
  5. Peter GEE

    Peter GEE

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    That is fixed but boiler refuses to fire up. On switching on the fan runs. I hear some gurgling but no ignition. Any ideas?
     
  6. ianmcd

    ianmcd

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    is the new AAV open ?
     
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  7. DP

    DP

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    I do not know if you can do this, but the will say anyway, the main heat exchanger has air in it. Needs to be vented manually
     
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  8. Peter GEE

    Peter GEE

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    Diverter valve functions with hot water tap turned on. Differential valve opens as expected.
     
  9. Peter GEE

    Peter GEE

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    Thanks. How does one vent the heat exvchanger manually?
     
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  11. ianmcd

    ianmcd

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    Not what I asked , I asked if the new Automatic air vent that you fitted is open ? it has a little cap like a car tyre valve if that is closed open it and it will vent the air from the boiler , might have a little plastic plug rather than a cap some do
     
  12. Peter GEE

    Peter GEE

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    Thanks . Yes that cap on the AAV is off at the moment.
     
  13. DP

    DP

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    By telling you how to do what I suggested, I would be breaking site rules regarding giving advice on area that is restricted. Needless to say you should be able to get the answer from the boiler manual :whistle::whistle:

    XXXI hint hint :LOL::LOL:
     
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  14. Peter GEE

    Peter GEE

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    Thanks.
    hello, Just out of curiosity if you have air in the heat exchanger how does that affect the burner firing? Is there some pressure sensor in the exchanger?
     
  15. DP

    DP

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    The operation of the various components is hydraulic. Air in the system will hinder operation of diverter and other components that rely on pump pressure to position them
     
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  16. Peter GEE

    Peter GEE

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    Thanks looks like getting the air out is not going to be easy. Can you bleed the diverter / differential.
     
  17. DP

    DP

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    No

    look at the hint. Cannot tell you more
    Purging air from HE is child’s play
     
    Last edited: 4 Dec 2021

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