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Viessmann Boiler - Water Leak and F5 fault

Discussion in 'Plumbing and Central Heating' started by stroller133, 3 May 2010.

  1. stroller133

    stroller133

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    Early this morning we returned from Holiday to find the boiler in Low Pressure alarm and Water all over the worktop - the boiler is a Viessmann Vitodens 100 30kw installed into the house from new in 2006.

    My first reaction was to top up the system using the top up loop to see if the water would come straight back out and to increase the pressure. As I filled it up the low pressure warning disappeared and the boiler attempted to fire up - I increased the pressure to about 1.4bar. After a few minutes of the pump running the Fault F5 appeared which apparently means the burner is blocked and the air pressure switch is faulty.

    After reading the book it appears there is a PRV that might have discharged the water, but my query is whether the the release of pressure would have caused the F5 fault and fixing this fault code would still leave the high pressure problem or whether the blocked burner would have caused the high pressure that activated the PRV.

    Please let me know what you think and whether my ideas are well off track? Either way I am going to need to find a Veissmann familiar engineer ASAP as it a combi boiler and we have a 7 month old baby to care for.

    Cheers
     
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  3. Agile

    Agile

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    You need to see if the PRV has been correctly connected to a discharge pipe going to the outside.

    You did not say if water is still leaking.

    The F5 fault is not obviously connected and relates to a stuck flap at the outlet of the fan. That requires a gas registered engineer to fix it. A Viessmann trained engineer would be best.

    As far as the water problem is concerned unless we know where its coming from then we cannot offer any advice.

    Tony
     
  4. stroller133

    stroller133

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    Thanks for your reply

    There is no fresh water today and the system is still at 1.4bar but obviously the system has not fired yet. Just wondered really if the F5 fault and water could be related.

    Outside there is a copper pipe, but I always thought this was for the condensate?

    It just seems really unlucky that unrelated two faults have developed at the same time. I left the boiler in frost protection mode while we were away, but set from the SALUS room stat not the boiler.
     
  5. Agile

    Agile

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    The condensate pipe is a convoluted grey plastic pipe exiting from the left hand side.

    There is no obvious connection between the water leak and the F5 fault.

    But your water leak is also unusual as it seems to have stopped now!

    Tony
     
  6. stroller133

    stroller133

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    Somebody has been out and freed off the flap now as it would have took a few days to get the new part.

    It seems to work fine now and he said it might not stick again so he is not currently ordering a part.

    If I order a part online then will it be the modified version - that way if it goes again I just need to call a gas installer to come and change the flap rather than waiting for one to come in.

    No further sign of water leaking either - bit of a mystery.
     
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  8. AkuraEngineer

    AkuraEngineer

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    it is not worth ordering the flap as its better removed completly!

    the original purpose for the flap was to stop snow from getting into the fan in Germany however when the vitodens where first imported to England due to our poor air conditions, polution or whatever else is in the air it has become comon place for for the flap to get stuck viessmann are aware of this and most people actually remove them completly

    the new vitodens do not come with the fan damper

    i have several collections of flaps at base
     
  9. mickyg

    mickyg

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    ha I've heard it all now. The wrong kind of air! Do you believe everything the manufacturers tell us? If you did then you'd think that in the rest of europe no boiler ever goes wrong as when ever something happens, "it never happened in such and such country". Codswallop.
    Could the F5 not be caused by a blocked condensate? and hence the water? just a thought.
     
  10. AkuraEngineer

    AkuraEngineer

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    cause not micky but thats not my biggest concern my main concern is fixing boilers and understanding comon place fualts i dont really care whether we have clean air bad air and i certainly dont give a monkeys about all this eco energy lets save the planet pc brigade either i just know the flaps like to stick and get stuck aparently its due to the air in reality its just a silly little extra that they have now realised shouldnt have been there in the first place

    ps phone ideal technical and ask them whether they have many problems with the response and see what they say that will make you luagh
     
  11. Agile

    Agile

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    The F5 seems to happen without any other cause.

    To me its amusing because I asked them if they advised removing it.

    They said the latest boiler dont have it. However, its part of the boiler as supplied and if I removed it then it would be contrary to the manufacturer's instructions so I would be acting ultra vires. ( My latin, not theirs! ).

    Tony
     
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