I had months of similar problems. Lately the green 'central heating' light starts flashing as the boiler changes state without being asked!
For me, moving my rf thermostat from the hall and leaving it about a metre away from the boiler seems to have done it - clearly needs a longer-lasting fix, but we are warm again.
My best advice is go to the Worcester website, where you can ask any question and their technicians get back to you the same day (or if late, tomorrow). If too slow, you can phone.
Their other idea was to reset my thermostat-receiver link, but all seems well so have not tried that. If you have lost your handbook, you can download them from the website too.
Keith Morgan, January 2013
