Re: Points from a briefing
The problem is that if your boiler is older than about 5 years, it is extremely unlikely to meet the current installation regulations. All it takes is for an over zealous gas-safe certified meter fitter to decide that even units fitted before this time should comply, and the majority of the country's gas central heating systems could be condemned.
I recently has this happen to a member of my extended family who was persuaded to have a boiler check by another family member, only to have a "This appliance is unsafe" sticker attached, and the gas supply turned off (fortunately at the gas tap in the house) because there was a bed being stored (not used) in the room with a well maintained back boiler in it, and a fresh-air vent that was over-sized but could be shut (a real no-no in the installation regulations). They also insisted in some decorative trim being removed from around the sides of the fireplace, and some insulation stuffed up the chimney (supposedly to prevent exhaust gasses coming back down the chimney, although what was used - standard insulation rock-wool - looked pretty gas porous to me), even though a proper chimney liner and baffle were in place (they just could not see it).
To be satisfied, the checker brow beat this family member to have another chargeable visit once the bed and close-able vent cover were removed.
And the irony of this was that the regulations quoted came into effect after the boiler was installed, and that for non-rented private houses, there is no need (or indeed a formal process) to get a safety certificate for an existing installation in the first place!
Still, I'm pretty worried anytime I have to let a gas-safe engineer into my house, because they could decide to condemn my elderly boiler almost on a whim!