Home DIY

Get a tado or nest stat to control the boiler: geo fencing to tell when you're home or away, set the timing on your phone, boost etc. If you feel like you need it later get some smart TRVs when they're on sale.

I realise that having the heating on from 7-8 and 5:30-10 is not a practical solution.

Then have it available for heat from 5am to 1am. With working dumb TRVs on the rads this is an acceptable solution.

You could even have it available for heat 24 hours a day - it will only fire when its own internal thermostat for the water circuit requires it to.

And with the TRVs preventing hot water circulation in the radiators when the room is the 'correct' temperature there is low water volume and nowhere for the heat in the circuit to go , save for bleeding from the pipes and towel radiators - but most people want the later on and the surface area of the whole lot is tiny compared to the entire system.

Boost buttons are weird; if you have TRVs controlling the temperature, a boost button won't really do anything. Assume they just override the timer / house thermostat but if you've set those up properly a boost button shouldn't be needed.

I had no fucking clue about any of this stuff until I went down the rabbit warren when replacing our central heating system, hot water storage and controller. Even the simplest system comprising of a timer and TRVs is adequate but conceptually too difficult for a disinterested consumer to really understand and get the benefits from and it doesn't benefit the fitter to recommend this solution and explain it, hence proliferation of 'smart' thermostats and complicated controllers.

@konastab01 I don't see the point in a single 'smart' thermostat unless it's in a small flat. I guess the geofencing thing is kinda useful and weather compensation is good but overall it feels limited compared to the control a smart TRV that can call for heat gives you and just adds complexity over a properly set up 'dumb' system.

tl;dr either go super simple - timer & dumb TRVS which is an easy fit to your existing system - or go balls deep and fit smart TRVs that call for heat on their own schedule everywhere to get the benefits of zoning without having to rewire and replumb. There are comfort benefits to going balls deep and if you have a requirement to keep a specific room at a specific temperature then it's justifiable but if you don't it's probably not worth the extra grand it will cost you.