Worcester Bosch Greenstar faulty

[Nicholas]

With regard to this fault ensure the timer for heating and hot water is demanding heat and then rotate the thermostat on the front of the boiler fully anti clockwise to the reset position and then back clockwise to the heat position.

Note that with demand the fan should now run, if not the fault with the boiler is a defective fan. If the fan runs and the boiler fires but rapidly gets to overheat check the central heating circulation pump is rotating and has power with a non touch voltage proving detector. If this has power and does not rotate you will need to change the pump.