this is a fault on the sime boiler and it would seem that i am the only one that knows how to cure it sime will tell you to replace the gas control pcb YES! this will cure it for you at a cost of £75. 00 for the pcb to do it your self you need to remove the pcb the one to the left of the boiler with a blue plastic cover after taking off the cover the pcb unplugs sideways to the left, from the gas valves, uplug all the wiring connections from the pcb then with a 10x mag eye glasslook at all the soldered peaks on the pcb and you WILL! find about 15 peaks have very slight cracks round them you need to look very carefully, re solder all the peaks and the fault is cured get some one who is able to do the soldering as it is very tricky,ps do not forget to switch of the power and the gas otherwise [BANG!]
BOBBY ROB
January 2007
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