I have a combi 28CDi to which the bar pressure keeps rising to 3 i have opened the radiator valve several times and drained off some water, this brought the bar pressure back to 1.5 but every 2 days it keeps rising to 3. Is there any thing else i can do to solve this problem. would be much appreciated.
Sounds like the expansion vessel has lost its charge. It is an easy fix but you would need to top it up with nitrogen not air or at worst replace it so best to get in the pro's as if it is not done properly will blow seals and all sorts in the boiler.
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