the hot water for the domestic hot water is leaking into the radiators, so that even when the central heating is off there are some radiators still warm, we have a pressurised heating system does this make repair costly and complicated?

penny, November 2009

d you are absolutely correct.....just read the post again and somehow I had thought that the pressure rising inside the boiler. (blush)

John, November 2009

the other guy is wrong if you have a combi boiler then it will be your diverter valve. If you have a sealed system with external valves then there will be a 3 ways valve or two 2-way valves and there will be an issue with the htg valve, or in the example of the 3way valve the hot water will be passing around the htg side of the 3 way valve.

d, November 2009

Your boiler needs a new DHW heat exchanger - as one is leaking into the other.

John, November 2009