HI, basically I have had the boiler for 5 years and its never been serviced but never had any problems and the rads water is very clean, when we first got the boiler the hot water temp was set at 55oc and the the shower and tap water was scorching hot but gradually the temp of water has got colder and even with the water temp turned up to 65oc the water out the taps and shower is just about hot enough, i measured the water temp and both the shower and taps were 39oc, I know the plate heat exchanger is not blocked as I had it off and cleaned it even though it was very clean anyway and also fitted a new pressure sensor, the display shows the temp getting up to 65oc but its just not coming out that hot, any ideas what it could be? any help would be much appreciated. Thanks.