Honeywell 7-Day Touchscreen Universal Programmable Low Volt Thermostat

Great thermostat. Have owned it for 7 + years. Well suited for regular weekday/weekend household schedules, but it is still very compatible for me on irregular/modified shift work schedule by using the "Hold" function during my days off. Also like the "Hold Until" function for weekends or vacations away, so house temp is comfortable when you return, saving you money. Excellent feature fills in well for non-Wi-Fi thermostats. Thermostat works fine without the "C" (common) wire, typical of a 5 wire harness in single stage HVAC systems, but recommended if available/upgrading. "Optional" batteries last longer as back-up power and facilitate armchair programming. Disappointed with the limited display-back-lighting feature. As one reviewer's reference of back-lighting only staying on during, and for just 10 seconds after touchpad usage (even with the thermostat hardwired) is accurate. Product images and specifications are misleading in that regard, as I too perceived it would be full time, or at least programmable. Packaging should reference the temporary state of back-lighting feature. Programmable back-lighting features should have been made available in hardwired installation mode, however, this feature is reserved for the VisionPro series looking otherwise identical to this unit, that typically contractors have access to. For this deception, I rate it at only four stars, otherwise a five star product. Tip: If you have a 4 wire system harness, and wish to have the "C" (common) wire function, and have a little or no need for the furnace "fan only" operation mode, move the "G" (typically green) wire to the "C" position at both furnace and thermostat terminals. Thus, you now have hardwired "C" (common wire) mode installation and batteries become optional.

We previously had a NEST thermostat but in the cold weather it loses power and will stop working unless you have a wire to the 'C' contact. This was very frustrating to say the least. If you are replacing your old thermostat check first to see if you have a wire to the C contact which most SMART thermostats require. If not then purchase this thermostat and have peace of mind that you will have heat in cold weather.

Yes, it's very easy to install and very easy to program. I installed it in my 50+ year old house which was 2 wired (black/red wire and white wire). Let's see if it'll actually save me some heating costs. The only thing is I wish it had a password function so my wife doesn't keep turning up the heat (or if you have renters).

I found the product features listed on the packaging for the RTH8500D regarding backlighting a little mis-leading. I interpreted the backlighting feature as being on all the time, to which after installation found out that the backlighting only comes on when the touch display is activated. The backlight feature on the packaging should be more clear on this, as I probably would have bought a different product. The RTH8500D is a little hard to view without the backlight on and a bit of a pain to always having to touch the screen to view the displayed information. I'm disappointed in this product, because of this. Otherwise I like all the other features that this touchscreen has.

Sur mon système à eau chaude, ce thermostat permet de maintenir une température constante et confortable, contrairement à ceux d'autres marques. L'écran facilite la programmation. Il permet d'anticiper les changements de consigne. J'aimerais qu'il soit possible d'avoir quelques informations de base toujours visibles dans le noir et/ou que les flèches pour monter ou baisser la consigne soient facilement repérables dans le noir.