Hi, I have had to replace the fan & housing as the old one kept grinding to a halt. When the hot water tap is turned on or the heating turned on the fan starts and then after about 15 seconds the red light comes on and no hot water. There is no ignition sparking to light the boiler.
Had to put the steel cover back on which acts like a like a sealed unit with it in place, which will then trip the air pressure switch which turns on the gas and lights the boiler.
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