Honeywell DT90E1012 digital room thermostat

Bought one of these 5 years ago, and was very worried that the constant "ticking" of the relay cutting in and out would fry the relay after a short time. I understand that the relay controls the call for heat, but it clicks away merrily even in the middle of the night when the heating is off. This is because it's a stand alone battery operated unit with a simple on/off relay, so doesn't "know" when the heating timer has been switched off. A conventional mechanical one would just call for heat when the temparature dropped, and that would be the end of it for the night. I am assuming that because it tries to do clever things with temperature control, it switches the relaay on and off more frequently. Anyway, I'm happy to report that so far it is still working perfectly with no sign of the relay failing. Hopefully with the fairly high price tag they have put some of it into high quality components.Pros:* Reliable* Simple to use* I love the "Eco" button that just drops the temperature for an hour.Cons:* Relay clicking could be annoying but isn't for me as it's fitted in the hallway.

I've replaced an old and inefficient mechanical stat with this digital unit and the early impressions are very good.Easy enough to install, the unit is standard size so easy to replace an existing. The stat simply wires in line with the live, providing a switched live return to timeswitch, so only a two wire installation (if earth and neutral exist in current stat, insulate them and tuck out the way). Included instructions are basic and mainly pictorial, but can be understood if user competent (if in doubt, get help).The stat itself provides a good number of options in a hidden menu to set-up, although all the defaults work ok 'out the box'. You can set maximum temperature for example, ECO temp etc.The stat is a doddle to operate, simply needing a press of either the up/down keys to adjust the target temperature required, and the display will show a flame symbol to illustrate if the heating is on, plus current room temperature.ECO function works well too. The single ECO button is pressed to select a predefined temperature (which you can set to suit) and ECO then runs until turned off. Alternatively you have the option to use the up/down keys to set a timed range between one and 24 hours for ECO to run. So if set to 5hrs for example, ECO will automatically switch off after five hours and the stat will return to work as normal again.This stat certainly controls the heating more efficiently that a mechanical device, as the switching threshold is far more accurate. The mechanical stats rely on the heating and cooling of a bi-met strip and suffer quite a lag in switching. Our heating has clearly run more consistently with this new digital thermostat.There seem a lot of comments regarding the loud click this stat makes, however mine gives off a very quiet click only (no louder than any other stat) and I'm struggling to understand how so many have complained; maybe they're just over critical.The ONLY criticism I have is the lack of backlight. Not a big problem but would have been a useful addition to have had a lit screen, for say 4-5 seconds once a button is pressed.Overall a great device and so far very pleased. Only reducing by a star as reliability so far an unknown quantity, plus lack of backlight.

Excellent product, does exactly what it says on the tin and more. Very well made, easy to fit and works well. Instructions are a little complicated, but if you have your boiler wiring diagram and browse a couple of youtube videos, you'll know what you have to do and the instructions become more of a guide. Becomes a bit complicated if you want to play about with the settings, but I don't see why you would need to as they are fine as they are. Haven't used the Eco mode yet, and it does have a frost protection mode which I didn't think this had but is a nice handy feature. It also 'monitors' your room temperature dropping and turns the heating on before your room drops below your desired temperature so it keeps your room nice and evenly heated. Finally, the dreaded 'click' on/off that everyone complains about, yes you can hear it, but I'm not exactly flinching every time it does it or burying the thing under pillows. Slightly louder than it needs to be yes, but nothing that has put me off the product or that I can't live with.

Beware, this is not the advertised Honeywell product, instead I was sent a similar looking thermostat made by a different (lower quality) manufacturer.

Have been having problems with our heating for a long time, had system flushed, serviced and even a new boiler, still not right.Need to turn thermostat up to maximum still only just enough heat. Decided to change the thermostat, more to modernise than expecting any difference.First read reviews, ordered this thermostat, arrived a full week early, well packaged. Having read previous reviews found it easy to fit, perfect replacement for my old analogue. Turned on heating and WOW, the heat was unbelievable, couldn’t touch radiators, have had to turn down setting on thermostat.Has been running for a couple of days now, am still very pleased. The thermostat looks good, is easy to use and offers a frost free setting.All in all couldn’t be happier and wish I had realised a long time ago a new thermostat could make such a difference.Would definitely recommend this Honeywell digital thermostat.