I moved into my house from new nearly 20 years ago. The gas boiler which runs the hot water and radiator central heating systems was surprisingly ‘top of the range’ considering the builders managed to install the cheapest bulk buys for much of the rest. However, in my case there is less work for the boiler as I live alone and therefore it’s not constantly heating water for childrens’ baths or endless wash cycles and dishwashing. The only time when there is a similarity with my near neighbours is heating. It needs to run at much the same temperature whether there’s one or 16 in the house with not too much variance. I do keep the radiator thermostats down in the rooms I use less of course. I was surprised to hear from my boiler service engineer, that despite having an opportunity to sell me something really expensive and worth his while, he chose not to and gave my dear old boiler another pat on the back as being still in excellent working order, despite her age!