Pressure Relief Valve and Expansion Vessel should be inspected, with the system drained and open to atmosphere, the Expansion vessel should be charged with air via the schraeder valve to 1-00Bar if the boiler gurgles and bubbles during pumping, it indicates that the vessel has failed and should be replaced, if vess holds at 1-00 bar, fill with water to 1-20 Bar, NO WATER SHOULD DRIP FROM DISCHARGE pipe, fire up heating, pressureguage should gradually rise to about 1-80 - 2-00 Bar, this is normal expansion, STILL NO DISCHARGE should occur
www.elanar.co.uk, March 2010
