@
Mailman
I'm not a great believer in annual servicing of gas appliances. Now I can recognise that a car with all those moving parts, metal against metal wear, drive belts, tyres, brakes, hydraulics etc means that an annual service is highly desirable. Gas appliances very much less so. there are hardly any moving parts, and little in the way of preventative maintenance that can be carried out. There are the more unusual situations where long flues are inside properties and leakage could be dangerous, but for the normal balanced flue boiler, hanging on the inside of an outside wall, I don't see the benefit.
Boilers come with inbuilt safety devices, Carbon Monoxide leakage is near impossible nowadays due to boilers working at negative pressure, and in home detectors act as a long stop. Where I do see a role for functioning smart meters is in detecting tampering with gas supplies. Although we haven't seen a spike in house explosions recently I would expect that cost of living pressures will lead to some taking extreme measures to cut costs through a by-pass of the meter with potentially catastrophic effects.
Presumably, the pressure after the gas valve was too high leading to inefficient combustion for you.
I also don't work to targets for energy consumption. I like to keep an eye on consumption because that drives costs, but I prefer to have set levels of comfort - I can't control the weather.