The boiler is working to a degree, it heats the hot water supply to the house perfectly but will not heat the water for the central heating. If I turn off the hot water and try and fire up the central heating on its own then nothing happens, if I try and fire up the hot water and central heating simultaneously then the hot water comes on but not the heating. Obviously the boiler is working, it fires up without any problem and makes no strange sounds, it just ain't giving me heat. The boiler is an Ideal Classic lxff and ff fanned flue gas boiler.

Andy Cleverley, October 2006

It sounds like your control valve isnt working, it could be a 3-way diverter valve or a seperate 2-way valve for your heating only, does it make any noise when you turn the room thermostat up or down?Bob

Bob, November 2010

I also have this problem, and the valve mentioned is ticking, what should I do next ?

Dave Holdsworth, May 2007

as you have said the boiler is fine. the problem either lies with the room thermostat or the mid position valve next to the hot water cylinder. With the room stat up and heating selected on the clock does the lever on the valve move over? can you hear the valve ticking?

Paul, October 2006