1. Visiting from the US? Why not try DIYnot.US instead? Click here to continue to DIYnot.US.
    Dismiss Notice

Vaillant Turbomax Plus - Intermittent F28 Lock Out

Discussion in 'Plumbing and Central Heating' started by 2point8ghiax, 3 Sep 2017.

  1. 2point8ghiax

    2point8ghiax

    Joined:
    9 Mar 2008
    Messages:
    92
    Thanks Received:
    0
    Location:
    Bath
    Country:
    United Kingdom
    Having an annoying intermittent fault on my 2004 Turbomax Plus 824e. It's started locking out with F28 code on average once a day. Some days it doesn't do it, but most days it just does it once. Usually after it's been used for hot water first thing in the morning. I re-set it, then it's OK for the rest of the day.

    Recently, we had a problem with the hot water going hot and cold. So, I changed the plate heat exchanger and fitted a Magnaclean on the return. Hot water performance is now good as new. The F28 fault started a few weeks after this work, so not sure if there is any connection. Boiler pressure is just above 1 bar cold.

    I'm aware that it's likely to be a gas or ignition problem. Would be grateful if anyone with experience of this problem/boiler, particularly when it's only intermittent, can tell me what to check for.

    Many thanks.
     
  2. Sponsored Links
  3. AGAS

    AGAS

    Joined:
    21 Feb 2014
    Messages:
    9,692
    Thanks Received:
    1,706
    Location:
    down south
    Country:
    United Kingdom
    You could try changing the water pressure switch other than that you need a gas engineer probably, so would be cheaper to get a gas engineer to start with ;)
     
    • Thanks Thanks x 1
  4. 2point8ghiax

    2point8ghiax

    Joined:
    9 Mar 2008
    Messages:
    92
    Thanks Received:
    0
    Location:
    Bath
    Country:
    United Kingdom
    Thanks for your reply. That would make sense. Looking at the manual, the pressure switch seems to be in series with the gas valve, so if it was faulty, I suppose the boiler could take that as a failure to light due to gas valve, hence F28.

    As we had a problem with corrosion in the water that blocked the plate heat exchanger, is it possible that debris is also blocking the pressure switch? Is it worth pulling it out and trying to clean it?

    Only trouble with getting an engineer is that, sods law, it won't lock out when he's present. Apart from the intermittent F28, the boiler works perfectly on ch and hot water.
     
    Last edited: 3 Sep 2017
  5. AGAS

    AGAS

    Joined:
    21 Feb 2014
    Messages:
    9,692
    Thanks Received:
    1,706
    Location:
    down south
    Country:
    United Kingdom
    could try cleaning it

    need someone who works on these tbh , there are settings regarding gas that can be changed to overcome this problem but we need to be in front of the boiler tbh and their are a few other things to check also(y)

    as it happens there are quite a few turbomaxs in bath ;):) as your not far from me ;)
     
    • Thanks Thanks x 1
  6. 2point8ghiax

    2point8ghiax

    Joined:
    9 Mar 2008
    Messages:
    92
    Thanks Received:
    0
    Location:
    Bath
    Country:
    United Kingdom
    Thanks again. Will try the switch first.

    As for Bath, that was in 2008 when I first joined DIYnot. Have moved to Devon since, but forgot to change my location as I don't come on here too often. Traffic and parking in Bath was driving me nuts. :mad:
     
  7. AGAS

    AGAS

    Joined:
    21 Feb 2014
    Messages:
    9,692
    Thanks Received:
    1,706
    Location:
    down south
    Country:
    United Kingdom
    Tell me about it it drives me nuts as well :mad: ;)
     
  8. DIYnot Local

    DIYnot Local

    Joined:
    3 Sep 2019
    Country:
    United Kingdom

    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.

    Select the supplier or trade you require, enter your location to begin your search.


    Are you a trade or supplier? You can create your listing free at DIYnot Local

     
  9. Sponsored Links
Loading...

Share This Page