CH boiler problem

All is working, no warning lights, radiators all bled, BUT. The water pressure dial is between 1 and 2 as it should be, but when CH is switched on it goes right up to 3, bordering on the red line. If I take a cupful out of the system it reverts to being o.k. Then when I turn CH off it goes below 1 and I have to top the system up again. Driving me mad. Any ideas please?
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Fauly expansion vessel. See
http://www.makewrite.demon.co.uk/SealedCH.html
--
Adam



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On 26/09/2010 12:58 PM, ARWadsworth wrote:

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