I have just defrosted the condensator pipe on my worcester bosh greenstar junior boiler. It will fire up ok now but only if I kep the on switch pressed in. As soon as I let go of the switch the blue light go,s out, Tried pulling the fuse and waiting a few minutes but still the same.
I have had a few of these with a dodgy on/off button, can only advise you persevere with pressing in the button until it eventually stays on. Alternative is a pcb replacement.
Once you have it on, use the fused spur to turn it off in future.
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