Hi,

My Myson Apollo 30B boiler now longer works. There's no pilot light.
While holding in the gas button I don't hear a hiss like my dodgy memory
suggests I did last time I lit the pilot light some years ago. Pressing
the spark button doesn't visibly do anything and no pilot flame ever
appears.

I've a call out to an engineer, but am I right in thinking that the
thermocouple is only concerned with keeping gas flowing once the pilot's
lit so it wouldn't be relevant here? Any typical faults, e.g. gas pipe
blocked, that may cause these symptoms.

Thanks,

Sam.