central heating pump continues to run when timer is 'OFF;

Discussion in 'Plumbing and Central Heating' started by ANDY55, 2 Apr 2007.

  1. ANDY55

    ANDY55

    Joined:
    1 Apr 2007
    Messages:
    1
    Thanks Received:
    0
    Location:
    Middlesex
    Country:
    United Kingdom
    I have a Potterton Prima F boiler and a (new) Honeywell 7 day programmer for water and heating. I have thermostatic radiator valves on all radiators and no room stat. I have a valve for the heating and a second valve on the hot water tank. both seem to be operating, in that the indicators on the outside of the valves move from time to time. As far as can tell, I don't have a frost stat (though am not sure what it would look like if I had one!). I had a new pump overrun switch fitted about 3 months ago.

    Intermittently, the pump continues even when the programmer has switched both heating and water off; this happened more often after the evening heating cycle than after the morning heating cycle, though it has happened after both. It can continue all night, and the boiler occasionally ignites - even though everything on the programmer is OFF! When this happens, the only way I can stop the pump is to switch off the mains supply to the whole boiler. The system worked fine for 10 years, but this problem started about a year ago which is why I changed the programmer, but this has not made any difference. I have no idea what to do, nor do the plumbers I have asked. HELP!
     
  2. Sponsored Links
  3. ollski

    ollski

    Joined:
    8 Oct 2003
    Messages:
    7,092
    Thanks Received:
    544
    Location:
    Bristol
    Country:
    United Kingdom
    One of the diverter valve microswitches is occasionally sticking on. I would imagine the hot water otherwise you would probably have noticed the hot rads.
     
  4. 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

     
Loading...

Share This Page