Locate the pump and check that it is runnng. It may be jammed or defective. Sometimes if you're lucky, a sharp tap on it may get it started, or maybe there's a screw in the middle you can undo and tweak it round.
Colin
January 2010
most likely a problem with the timer / room thermostat.
Ian
January 2010
Hi Mary
I have the same problem but with a Vaillant boiler, the hot water is fine (But too hot)and the heating isnt working I looked at the pressure Gauge and its at 2 bar, I'm a bit scared because normally it should be at 1 bar, I really don't know what to do :(
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