My first boiler - a Potterton floor standing BE BF type did need a service
once in a while. Otherwise it would soot up and stop working. I'd guess
modern units burn more cleanly?

I reckon most these days don't need a service as such. Just a check they
are working OK.

The one fault I've had with my Viessmann was a burst hose, and the water
spill took out the gas valve. But don't think an annual service would have
picked that up before it happened.

BTW, the gas valve getting soaked also took out a fuse on the PCB. A
soldered in PCB mount type. A gas fitter fixing that would likely have
just fitted a new PCB. And charged me for it.

--
*Very funny Scotty, now beam down my clothes.

Dave Plowman London SW
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