Hope someone can help. I have good heating but very poor hot water. the more i turn the tap on the colder the water gets. I have a new heater exchange unit fitted, i have reconditioned the diverter valve, i have changed all diaphrams, all pressure is normal 1.5 bar, flame fires up as normal but still only luke warm water, if i slow the flow down at tap it gets warmer but it would take a week then to fill a bath, any ideas? i'm also going to change the thermistor in a moment.

FrankBailey, February 2014

Was it a sudden thing or a gradual tailing off of heat? I'm not a boiler expert but i do trouble shoot with electrical problems and i would go through it logically by asking certain questions. As I'm aware when DHW is required the burner comes on to full,the pump does not run and no heat leaves the boiler through the c/heating pipes,is this what is happening? If so i still think the valve is not opening enough to give you the heat you require for a good hot water flow

toptrish, February 2014

thanks for your reply. the high flame is coming on upon demnd. the other parts replaced was during last 6 months or so as part of other problems.

FrankBailey, February 2014

Is your boiler reaching high fire or is it just the standard flame for heating,did you replace the heat exchanger for the same reason,with everything you have done you don't seem to have hit the correct reason,I know this is hindsight but you would have been better getting an expert in

toptrish, February 2014