Try bleeding radiators to get rid of air, Then with system cold try to increase pressure, you should hear the water going in, same as you do running a tap or after flushing the toilet. Might take a minute to start to increase, If not and pressure does not increase, could be a valve problem, with the fill loop. close it off, disconnect from boiler end, should be a valve/one way fitting to stop any water coming out of system. then open the valve to a bucket or something, see if you get water out, if not valve fault or 1 way fault or some other valve. Pressure to about 1 bar COLD
SD
April 2012
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