A thermostat is the one connected device I was nervous about, because when it goes wrong the whole house is cold and everyone knows who installed it. I read a long walkthrough on Next Home Gadget before touching anything, and that saved me from the worst mistake, the one about wiring.

Compatibility first, and I mean the boring version. My boiler has two wires and no third one, so the clever model on the box was out. I took a photo of the wiring inside the old unit, sent it to the shop, and got a plain yes or no before paying. Do that. Guessing at wiring is how people end up calling someone on a Sunday.

Then the learning part. These things watch when you are home for a week or two and build a schedule from it. That works, as long as you live a normal week during the learning period. I set mine up during a holiday week, and for a month the house was warm at strange hours.

Rooms heat differently, which the app never explains properly. The hallway stays cold, the bedroom upstairs stays warm, and one radiator does most of the work. I ended up turning the bedroom radiator down by hand and letting the thermostat look after the rest of the house.

I stopped chasing features after a while. Geofencing, weather compensation, room by room schedules, monthly reports. I use two settings and a timer, and the rest of the menu I open twice a year and close again.

Watch the first winter before deciding anything. Not the first week. A full winter, with the cold snap in January and the week in February when the wind comes from the wrong side, tells you whether the thing is actually saving you anything or just moving the cost around the calendar. Mine was fine. A neighbour found out in February that his was not.