I recently had error code F75. Pressure was low and boiler locked out. I put pressure right and turned boiler off then on to clear fault. Hot water now OK, but with CH turned down(Well it is summer now!!) the radiators get warm especially when hot water is being run. Any Ideas please? Installation is about 2 years old.

Geoff R, May 2010

diverter valve is sticking and passing through to radiaters

bob the boiler, May 2010

diverter valve seized, replace part

Mivy Gas Safe, May 2010

I don't know if your boier is the Eco-Tec, if so then I just wonder after your restored the system pressure why it needed to be switched off/on when there is a reset button.Anyhow I believe that you have a 3 way valve problem, why don't you isolate the flow v/v leaving the boiler on the c.h.side to prove this, whilst in the Hot Water mode. I would also just reset the boiler just incase some logic hasn't been reset.

Guytawe, May 2010