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Discuss Greenstar 27cdi Worcester boiler - Clock problems!! in the Central Heating Forum area at

  1. Mungobaby

    Mungobaby New Member

    I'm a newbie to this forum so hoping someone can help with this as sick of getting up at 5am to a cold house!!!

    i have just moved into a new house and the boiler is a Worcester Greenstar 27cdi - boiler works fine when using the on/off control however when I tried to use the timer (mechanical MT10) it wouldn't work, it was like the clock was ticking but really slowly so for example at 1pm it would still be stuck at 10am!!

    Anyway - we replaced the timer this weekend which wasn't a big job thinking this would resolve the problem, initially it seemed to be ok as clock was ticking round but again this one is now not working!

    so I am really asking for advice on if this is a duff timer that we have replaced it with or could there be a problem elsewhere on a circuit board which is preventing enough power getting to the clock? Don't want to buy another timer for the same thing to happen again. (I know the MT10 aren't great anyway!)

    Ive searched everywhere to see if there's any advice on this issue and can't find anything so thinking it may not be a common thing?!

    any advice would be greatly appreciated

    thanks in advance
  2. Gasmk1

    Gasmk1 GSR

    as you say MT10s are not great it is a common thing with them wont work on auto the switch goes faulty. you could have bought a faulty one replace it with a wireless stat, one of theirs or remove it and replace the blank and fit an external one.
  3. ckyens

    ckyens New Member

    You can get a digital replacement for the mechanical MT10. Easy enough to fit.
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