boiler loses pressure down in red when I pressure it back to 1.5 it expands to the red 3 bar and releases water. when bolier switched off gauge says 0bar but it still lights upand works fine I have changed gauge as i thouht it was faulty but still the same. Bled the rads they are air free
either the pressure vessel is faulty (needs recharging or replacing) or the pipe to it is blocked a sign of this is when you try to fill it the pressure goes up very very quickly
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