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

Combi boiler / HW switching problem - every 4 years...?!

Discussion in 'Plumbing and Central Heating' started by Libarch, 12 Nov 2017.

  1. Libarch


    9 Nov 2017
    Thanks Received:
    United Kingdom
    Hello, I have a Worcester Greenstar 35CDi combi boiler, installed in early 2006. Generally I have had no problems with it. However on three separate occasions - at roughly equal intervals, most recently yesterday - I've been away and come back to find that the HW doesn't work. And after a day or so of head scratching, instructions-reading, torch-pointing, more head scratching and chin stroking, it starts working again and normal service is resumed. A bit more detail:
    1) All 3 times happened after being away, for periods between about two days and four weeks;
    2) All 3 times was in the cold season;
    3) Opening a tap, the HW will briefly run hot, but then cold - meanwhile the boiler continues to burn, and the CH comes on (I think - that's what happened the last time, certainly).

    The reason I'm posting is that I'll need to get the system drained down quite soon to do some other (non-boiler) work, so if there is an obviously faulty component (eg the diverter valve?), it would be a good opportunity to get it fixed. But what sort of problem happens every 4 years and then sorts itself out like this? Does anyone have any thoughts?
  2. Sponsored Links
  3. dilalio


    20 Mar 2009
    Thanks Received:
    Potters Bar
    United Kingdom
    Sounds like diverter valve, pin, microswitch issue.

    Any valve is best maintained by regular exercise/manipulation. Constant drawing of hot water does this and even a couple of days of it not being used, on an ageing and particularly poor part (wb!) can leave it stuck. Try lubricating mechanisms with some Plumbers grease/ Silicone spray or at worst wd40.
  4. DIYnot Local

    DIYnot Local

    3 Sep 2019
    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

Sponsored Links

Share This Page