When I call for hot water the boiler sometimes doesnt light,yet other times it will but the water takes a long time getting warm.I find I have to turn the tap on and off of a few times before warm water wil come through.
if the water pressure on the warm tap gets weeker when u open it then you have a scalled up heat exchanger. if the pressure remains the same check the flame and see if after a few seconds of turning the hot water on it increases. If not there is a promlem with the flow switch or air pressure switch
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