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

Ravenheat CSI 85T

Discussion in 'Plumbing and Central Heating' started by steve28, 2 Sep 2008.

  1. steve28

    steve28

    Joined:
    30 Nov 2005
    Messages:
    62
    Thanks Received:
    0
    Location:
    London
    Country:
    United Kingdom
    Hi all,

    Have a CSI85t thats developed a strange problem.

    When the heating is OFF and set to SUMMER ie HW only, the boiler fires up fine when a tap is turned on and hot water is drawn, BUT the radiators get hot.

    This happens whether or not the switch is set to HW only or CH and HW.

    i've checked the thermistors by substitution and they are fine. When a tap is opened and the boiler fires, it runs on a while after the tap is closed again (few mins) heating the rads before switching off. The rads are getting excessively hot.

    I'm thinking the PCB could be at fault because the CH runs even when its supposed to be isolated.

    Anyone got any other ideas?

    Thanks in advance for any suggestions.

    :)
     
  2. Sponsored Links
  3. dangermouse46

    dangermouse46

    Joined:
    10 Aug 2008
    Messages:
    21,424
    Thanks Received:
    6,284
    Country:
    United Kingdom
    diverter valve faulty/jammed/letting by?
     
  4. twgas

    twgas

    Joined:
    26 Oct 2007
    Messages:
    4,900
    Thanks Received:
    426
    Location:
    Kent
    Country:
    United Kingdom
    sounds more like a diverter problem than PCB to me.
     
  5. steve28

    steve28

    Joined:
    30 Nov 2005
    Messages:
    62
    Thanks Received:
    0
    Location:
    London
    Country:
    United Kingdom
    Thanks guys -

    Ill check that and see if the valve is jammed open/half open.

    I assume its a mechanical valve and just needs unblocking but notice theres a diaphragm kit for it - so could that be perforated causing the problem?

    Would you recommend replacing the whole thing or just attempting the diaphragm replacement first?
     
  6. dangermouse46

    dangermouse46

    Joined:
    10 Aug 2008
    Messages:
    21,424
    Thanks Received:
    6,284
    Country:
    United Kingdom
    change the whole valve, guts are ruined.
     
  7. steve28

    steve28

    Joined:
    30 Nov 2005
    Messages:
    62
    Thanks Received:
    0
    Location:
    London
    Country:
    United Kingdom
    Well,

    after dismantling the valve I discovered there had been a leak from the top union - this had leaked into the microswitch and corroded it. NC/NO/C all open cct.

    I took the valve apart and checked but the inside seals looked fine, so I have renewed all 5 washers, and will be fitting a new switch tomorrow.

    Thanks for your help and advise.

    :D
     
  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