I have valiant ecomax 828 and pressure on c/h rises to 3 bar when heating is on but drops to 0 when off. I think this is due to lack of pressure in expansion vessel? If so how easy is it to repressurise and to what pressure ?
drain water from boiler and recharge expansion vessel at shrader valve on expansion vessel... precharge to 0.75 bar if it won't take charge probably got a hole in the diaphragm
may also need to change pressure relief valve
dazza
March 2009
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