pump may be seized.if it is accessible, at the head of the pump there is a disc usually chrome colour, open with a slotted screw driver (using a cloth to mop up a small amount of water)and insert a smaller slotted screwdriver until it engages the shaft twist it back and forth to loosen it, then reassemble the disc.switch on heater.if this doesnt work maybe check water levels/pressure in system. boiler will not fire below 1 bar pressure.
davy 47
October 2010
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