1) with No water pressure on the boiler gauge.
check what air pressure you have in your EXPANSION VESSEL this may be EMPTY,(if water comes out the car valve the E V is SHOT replacement needed) Try re inflating up to 1 bar max pressure, using a car foot pump & tyre pressure gauge,
2) Now repressurise (fill up) on the water side via filler loop to 1.5 bar cold, disconnect the filler loop.
wirecutterman
February 2010
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