Gas boilers, almost all homes in the UK have them, but they are dreadful! +90% of the ones I've seen are badly spec'ed and horribly configured, so they burn way too much gas. Then Martin Lewis keeps telling us to "lower the flow temperature" but it's never really explained how to, or what this does to save gas (and money). Well have I got a Slide Deck for you!! As with any serious problem, it needs hard data. So I wired my Raspberry Pi home server to my central heating controls, wrote a bunch of code, and spent last winter collecting data from my boiler, a dozen temperature sensors, some humidity sensors and the Octopus Energy API. I have pretty graphs to show what happens all around my home, how altering the flow temperature works, how altering set points work, why my house was too cold, then too hot, and used way too much gas. I'll explain the (simple) physics and how to tweak your system for best performance too. But ultimately, we all have to stop burning gas and move to heat pumps, a solution not understood by many and requiring something of a mind shift from the way gas central heating has always worked. I'll explain how heat pumps work and what you can do to prepare for their arrival in your home. The future is bright, and it's heading rapidly in this direction.