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Glow worm flexicom 35cx leaking PRV

Discussion in 'Plumbing and Central Heating' started by danoid, 20 Mar 2021.

  1. danoid

    danoid

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    This is happened a few times in a few years, but I noticed my boiler pressure was 0.8bar, so I topped it up to 1.1bar turned the heating on and away it goes.

    I went outside and noticed the floor was wet and water is slowly dripping from the PRV, I turned the heating off went to the boiler and it’s reading 3.4bar now slowly coming down.

    This only seems to happen when I top the boiler up to increase the pressure.

    There are no leaks coming from the boiler internally, just through the PRV.

    If I let out pressure so it’s around 0.8/0.9 again (back to square one) then it’s fine, but I believe the boiler pressure should be around 1 to 1.5bar normally.

    No errors on the boiler even at 0.8 bar, just something I noticed and no errors at 3.4/3.5 either even when there’s a drip from the PRV.

    Any ideas what’s up with it?

    Thanks

    P.S i’ve turned the CH off now and will check in an hour or so what the pressure reads once it’s cooled down
     
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  3. Stadan20

    Stadan20

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    Your expansion vessel atleast needs looking at. Call your local gas safe guy
     
  4. Sonic70

    Sonic70

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    You say it works ok when pressure is set to 0.8/0.9 bar but when you turn the heating on what does the pressure go up to?
     
  5. Stadan20

    Stadan20

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    It's a flexibomb. The low water pressure sensor is giving off the wrong reading hence it pishing water outside (y)
     
  6. Sonic70

    Sonic70

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    Stadan20 I was just thinking that if its set to 0.8 bar when cold that if there's a problem with expansion vessel the pressure could be rising close to 3.2 bar but not quite so the prv isn't going off but the OP thinks its running ok but it really isn't. I'm just a diyer only so probably wrong.
     
  7. Stadan20

    Stadan20

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    Probs a mix of things ... prv letting by . Digital Pressure giving wrong reading . Expansion vessel flat and filling loop letting by
     
  8. danoid

    danoid

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    To be honest i’m not too sure as it doesn’t leak through the PRV so never think to look after the heating is off, as it’s a digital display and only shows pressure when it’s off.

    Since turning it off today and the system is cooler it’s on 1.2bar now, when I filled it up today it was to 1.1 bar but believe it was closer to 1.2
     
  9. danoid

    danoid

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    Does that mean like now it’s reading 1.2 bar now it’s cooled off it’s possibly displaying the wrong figure? And more like 2.2 bar?
     
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  11. Stadan20

    Stadan20

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    Sounds like it's more of an expansion vessel issue but you need an rgi to check . I would be replacing (if needed ) prv, Pressure sensor and topping up expansion vessel
     
  12. Sonic70

    Sonic70

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    If you turn the thermostat right down once the heating is up to temperature doesn't it then switch display the pressure.
     
  13. danoid

    danoid

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    If the expansion vessel is likely to be the culprit, i’m guessing the first thing would be to pump to 0.5bar (max for 35 cx) and see if it holds the pressure.

    If say the pressure is 0.1 for example, would this cause the issues i’m having?
     
  14. danoid

    danoid

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    I believe so, i’ve got the horrible glow worm wireless thermostat so just as easy to select off
     
  15. dilalio

    dilalio

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    Very likely the EV. They usually need regenerating to atmosphere at least once a year... K.I.S.S... Start with the most likely.
     
  16. danoid

    danoid

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    Ah, I guess the EV is checked & topped up during it’s annual service? Which it hasn’t had for almost 4 years
     
  17. dilalio

    dilalio

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    It should be, but isn't always and is often done incorrectly... By a lot of service Operatives, I unfortunately have to say.
     
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