try turning your heating off and start from cold..
does your boiler fire up or make any noise ?
if it doesnt and you can get heating it is likley to be your water flow switch or divertor valve depends what model you have.
if it does make a noise ie fan start or similar then you could be looking at fan pressure switch or if it actually sparks ( heard tick tick) it could be gas valve
tech boilers svs
February 2009
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