My wall hung Vaillant condensing boiler is providing hot water but not central heating and does not show a fault on the screen. Can anyone help me please? I have checked all the radiators and they are fine so the problem is coming from the boiler somewhere and the thermostat is working well, thank you.

Lisa, November 2009

what model boiler do you have

Charlieboy, November 2009

by your hot water tank you have a 3 way valve it lets you have hot water, or hot water and s/heating at back of valve is a manule lever ;it will give you s/h h/w till you get new valve. unless your boiler is a combi!!

gas man, November 2009