Thanks Simind, much appreciated and very informative!
The boiler is one of the 'older' style ones with two knows, one for heating and one for HW - do you still think it could be the range rating though?
Many thanks again,
Shane
Hello I have a valiant boiler eco-tech plus. The hot water is working fine however, heating no matter what temperature, goes into (what I think to be) anti-cycling mode.
This results in the heating never going above a lukewarm temperature.
Without knowing anything about boilers, plumbing or...