Can a boiler pass a gas safety check, but not work?

FataVerde

hannahcolobus said:

Yes and no- the gas safety check is a minimum and you really only need the boiler to be able to work for enough time to be able to do your safety checks. 

So it won’t be a guarantee that the appliance itself works as well as it should. Also, it could quite easily develop a fault after the check so if it’s done really far in advance then it’s not really much use.

I’d be more inclined to ask for the benchmark which will show if they’ve had it serviced each year, proof that it’s been looked after and serviced each year will be a far better indicator of whether it will
work when you get in there. 

I've done a service (boiler currently working) precisely because they had never serviced the boiler in 6 years of living at the property.