Honeywell Home THR99C3110 Smart Wireless zoning Thermostat, White, 139x101x21mm, Set of 2 Pieces

After much research, I found this to be easily the best smart thermostat on the market and it goes the whole way by controlling individual radiators in addition to the central heating boiler. Every room has the right temperature at the right time.It's been about 3 months and we have not experienced any issues controlling this system remotely. Additionally, though all the controls on the thermostat are not available on the smartphone apps, this is not really detrimental.We bought 8 of the HR924UK radiator thermostats to go with this and the pairing went quite simply by following the instructions. I already had a very basic wireless thermostat which had been installed professionally, so I was able to connect the wireless module (this is separate from the thermostat but comes in the box) myself by following the wiring diagram at Honeywell's website for installers. Note that if you don't already have a wireless thermostat or you have the smallest doubt about connecting the wireless module, get a certified professional to avoid risk to life and property.Once everything is installed, you're on your way - you can name each thermostat around the house and decide what the temperature should be at different times of day in each room (the thermostat allows up to 10-minute precision). The thermostat touchscreen comes with a wizard to make this simple, or you can control the schedule with more control.The HR924 radiator thermostat regulates heat by opening and closing the valve as directed by the programmed schedule. There's a little noise as the motor turns, but after a while, you learn to tune it out. This combined system of the touchscreen thermostats and radiator controllers is very well thought out and includes options like always making a particular room a little warmer or cooler than the measured room temperature and showing which room(s) have caused the central heating boiler to come on. There could be some improvements (the battery life when the thermostat is moved from the base seems short and some features could be made more easy to access) but this has been one of my most satisfying purchases for a while.

It was an expensive investment to fit a large house with all the necessary radiator valves, but I am now consistently making savings of more than a third of my gas usage, measured over the first three months of 2022 compared with 2021. I'm writing this on 1 April 2022, a day when everyone's energy prices are rocketing, so I'm doubly pleased with this investment--I originally thought it would take years to repay the cost, but now it's going to be measured in months.Previously I had thermostatic radiator valves everywhere, but only one room thermostat, so edging up the temperature in the one main room for temporary extra comfort meant that heat was likely to be wasted everywhere else in the house--in effect there was only one control zone. With this system, almost every individual room is its own zone, and I can programme them for temperature and timing individually.Although we're using so much less energy, it's become very easy to focus where the heat goes and when. That means, for example, that the the living room can be heated quickly at a time when other zones are less important and programmed for lower temperatures, whilst the bedrooms can be left to their own devices for most of the day but warmed effectively overnight. The house feels more comfortable than before because the system is just so much more responsive.The central unit is easy to use, and the Total Comfort app supplements it by allowing more than one user to make adjustments--so when someone leaves their bedroom/home office for the evening after it's been heated all day, they can save energy by turning off the heat for that zone, maybe just for that evening.I did a totally DIY installation, but I would not necessarily recommend that for the faint-hearted or untrained buyer. Having researched other brands of smart thermostat systems and decided on Honeywell, I bought the kit and experimented with it as a dummy system, not actually controlling any radiators, nor connected to the boiler, until I understood how the programming works and could control a specimen valve at will. Then I gradually added the zone valves (in my case all my existing radiator valves were by Honeywell and the physical fitting was a breeze), and progressively changed the system wiring to use the new programmer instead of the old one (obviously that's the electrically challenging and potentially dangerous part). There was a fair bit of head-scratching along the way, but I'm really pleased with the result.

The good points about this control panel are that looks good and has lots of features for controlling the central heating system. It's pretty straightforward to use and the instructions provided are easy to follow to get you started.I would have given this device an extra star but for a few things which I feel could be improved. Firstly, the touch screen - it's not very responsive and I find I often have to press on the screen several times before it reacts. Secondly - since this device connects to the Internet, there ought to be an option to export your settings (that would also open up the possibility of being able to save more than one profile for each connected device). Lastly, the idle screen - it's way too bright and there ought to be a way to make it less bright without having to reduce the brightness of the settings screens. An option to have a white clock on a black background (as is currently available in night time mode) would be a good feature and there should be an option to completely turn off the idle screen at night as even with the white clock on a black background, it still lights up my bedroom if I leave the door open for ventilation.

Can take a bit of time to bind, set zones and schedules for the first time for a diy"er. Once you get your head around set up, product works great. Pricey but great great product.