Saunier Duval Thema Condens F24E pressure dropping daily

Discussion in 'Plumbing and Central Heating' started by MadLizzie, 15 Mar 2010.

  1. MadLizzie

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    Our boiler is nearly 3 years old and has recently had an annual service and passed fine. We have heating and hot water without problem but for the past few weeks we are having to top up the pressure once or twice daily to keep it above 0.6. From reading other posts am I right in assuming we are likely to have a leak somewhere? The whole central heating system and piping was newly put in 3 years ago, no copper pipes, all 'plastic' tubing. I am worried that we have under floor piping in the lounge which is under laminate as I think we might have a pipe connectionj under there? What option do we have before taking the floor up?
    Thanks
     
  2. adlplumbing

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    increase the pressure to 3bar and see if their any obvious leaks
     
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  3. MadLizzie

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    Thanks, I have noticed that the towel radiator which is only about 6 metres away from the boiler, has had some external gunk where one of the rungs joins the vertical post about 4 rungs up from the bottom. If there is a small leak there could that cause the continued drop in pressure?
     
  4. adlplumbing

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  5. mickyg

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    Check the pressure relief pipe first. Should come out of the boiler and go outside and terminate into the wall. Should be dry as a bone.
     
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  6. Agile

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    Even if its a dry as a bone then still put a plastic bag or condom over the end and check it the next day.

    Tony
     
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  7. MadLizzie

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    spot on - it is not dry but when we had the service donw it had been raining so we didn't notice it. I think we have found the source of the pressure drop. There is a small stream of water trickling down from the little copper pipe sticking out below the flue. Our gas man says that this is likely to be either a faulty pressure valve (can't remember what he called it) or that it might have some gunk in it. He is coming to have a look but is it really likely that it could be broken when it is not even 3 years old? What sort of reputation does this type of boiler have?

    By the way, thanks for all your help and advice!
     
  8. Agile

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    This boiler has a dreadful reputation and that brand is no longer sold in the UK. You still get equally as bad ones under the G-W name though.

    A car tyre will fail after one week if you dont keep it pumped up.

    The PRV will leak if the system is dirty. Installers dont properly clean a system when fitting cheap boilers.

    Tony
     
  9. mickyg

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    absolute codswallop. I bet you've never seen one.
    All the earlier SD boilers were pretty poor, granted, but this is not one.
    The themacondense is a combination of GW and Vaillant parts. Its a decent boiler and reliable. The only thing I would suggest is having an external filling loop fitted as the internal one is probably the only weak spot on this boiler. SD stopped selling in the UK but they still provide service and spares and most parts are the same as used in glowworm and vaillant boilers. Unfortunately Tony only ever works on the older models and assumes that they must all be the same. :rolleyes:
     
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  10. nogoodatfaultfinding

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    Also ask your Service guy to check your expansion vessel when he comes back now.
    Why these 2 parts were not checked on your service i will never know.
     
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  11. Agile

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    Although I do normally avoid anything with the name S-D on it I have had to do repairs on one which was sludged up. Assuming its the same model it has a rather unique long thin filter to the front right of the pump just to show my product knowledge.

    That boiler's plastic parts still look very similar to the non condensing model where the plastic splits and sprays mains water all over the two PCBs turning a £200 repair into a £450 repair or ideally into a replacement boiler which is not called S-D.

    But I should not be so negative as G-W are taking some of us out to dinner tonight! Unfortunately to a Chiquito rather than a slightly cheaper Indian where the food would be better.

    Tony
     
  12. mickyg

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    So you've seen a grand total of one and from that you've decided that it has a poor reputation even though it was full of sludge and likely not the fault of the boiler?
    Have you seen an SD Enviroplus? Another decent boiler from SD with a really good ally heat exchanger from AWD in Holland.
    All the later SD products were excellent value for money, unfortunately the reputation was already ruined by the old rubbish.
     
  13. Agile

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    I agree that the S-D name was spoilt by a succession of poor quality boilers.

    Then came the range that seemed the same as G-W boilers and leaked mains water everywhere.

    Then that condensing boiler which did not seem to have anything seriously wrong with it. But by then 20 years of producing seriously flawed designs had paid its toll.

    They also later on were the first manufacturer to introduce a premium rate telephone number, make you wait five minutes to make sure you had paid more for the call ( and continue to give non-premium advice quality ). For doing that they deserved to fail in the marketplace.

    Tonights GlowWorm dinner was good fun and Chiquito seemed to have recruited a new chef as the food was quite good. Pity about the service though, it seems they cannot get the staff nowadays.

    Tony
     
  14. millibar21

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    done loads of work on s,,d and g w and to be honest they are a pain in the a**
     

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