RTH221B1039 RTH221B Programmable Thermostat, White

GREAT thermostat. Way better than the old mercury switch, but still nice and dumb so it doesn't need or even have the ability to connect to friggin wifi. Works great for a three wire connection controlling an old electric forced air furnace. Setup is easy and instructions are pretty good. I really like the simple wake, leave, return, and sleep programming. If you're the kind of person that still doesn't wear a smart watch, then this is your thermostat.

I purchased this programmable thermostat to install in the portion of my two-family home that I live in. I also purchased the similar Honeywell RTH111B Vertical Digital Manual Thermostat NON-programmable model for the portion of my home that I rent out. Installation of both models is identical, and the main difference between the two is just the ability to set up a program of varying temperature changes based on your schedule. The non-programmable RTH111B has no clock feature. Just simple buttons to change the temperature up or down, and switches for a system fan (if applicable) and the HEAT-OFF-COOL selection. The programmable RTH221B gives you these same features, PLUS a 7-day, 4-event schedule to work with. In other words, every day of the week is treated the same and you can program in a time and temperature change for waking, leaving, returning, and sleeping. For people who desire to have a different schedule for the weekend, a 5/2 day programmable model would be a wiser choice. The apartment that received the RTH221B is a simple heat-only, oil-fired steam radiator system. The installation instructions were generally easy to follow, but I also found additional information on the Honeywell website explaining what each terminal actually was. It would have been useful for Honeywell to print this in the instructions. Summarized: Rh : Heating power supply Rc : Cooling power supply W : Heating signal Y : Cooling signal G : Fan Both of the two environmental systems in my home are ONLY heat, and have a two-wire connection. The wiring looked about a hundred years old, but still worked perfectly once I connected the wires to the Rh and W terminals. Interesting to note that in both installations it did not seem to make a difference which of the two wires went to what terminal, so long as it was Rh and W. However in a more complicated system that includes more wires for cooling or a fan, I'd use the included labels to mark each wire and be certain it was connected properly. Following the instructions, setting up a schedule for temperature changes was a simple process. Even if you ONLY wished to alter the temperature at night (rather than during the day while at work), it's a breeze because you'll just set the temperature the same for the "leave" and "return" events. Overall, setting the clock and programming took only a couple of minutes. I don't have any dollar amount savings to offer, but I can say that the temperature was MUCH more consistent in my apartment than it had been with the old round-style mercury switch which was prone to large temperature swings. There is no question in my mind that less fuel was used, and it's very likely that the two thermostats I purchased have already paid for themselves one month later.

This thermostat does exactly what it’s meant to, keeps your home at a comfortable temperature without any complicated setup. Installation was quick and straightforward, even for someone who’s not super handy. The instructions were clear, and it powered right up once connected. The display is easy to read, and the programmable feature is great for setting different temps during the day and night. It’s not fancy or smart-home compatible, but that’s also what I like about it, fewer buttons, fewer issues. Once set, it keeps the temperature steady and accurate, and it’s easy to adjust when needed. If you’re looking for a no-frills, dependable thermostat that just works, this one’s a solid choice. Pro tip: double-check your wiring before installing, it makes the whole process even smoother.

Replaced some old mercury 2-wire thermostats for my oil-fired furnace. No a/c. Wanted programable, but that was about it. These fit the bill. If you want each day to be individually programable, then you will need the more expensive model. This one is about half that price. This one is simple to set and simple to override if you want. Installation is easy. Remove old 'stat (note which wire was connected to which terminal, say red or white), feed the wires through the baseplate from the new thermostat and attach with the 2 included anchors and screws to the wall), and then screw the wires under the approriate set screw terminal locations that are labeled on the baseplate. For example red to red-heat (r-h), white to white. Add 2 AAA batteries (not included)to the thermostat cover and snap into place. Then program with time and set temperatures. I did four thermostats. The first one took about 25 minutes (most of the time making sure I knew which wire to hook to which terminal), the other 3 took about 10-15 minutes each. One other note. I found one degree of variation from other digital thermometers (if you check it against another one) but once set it is very stable. Update: Corrected battery size to 2-AAA. - Battery replacement is a snap ... less that 5 minutes each thermostat. Loosen the bottom set screw a couple turns (don't back out completely or you may loose it) and pull of cover from the bottom. Batteries are located in the cover and if you replace them right away you don't lose your settings. Reattach to base by setting the top first and then closing in the bottom, you can tighten the screw to hold in place. - There remains a difference between the temperature reported by the thermmostat and my other, professional indoor outdoor thermometer. These thermostats are off by about one to two degrees higher. When the actual temperature is 70F, these four read 71F or 72F. In other words, the actual temperature is about 1 to 2 degrees lower than what these thermostats show. - Two of my thermostats have the sensing thermocouples sealed (silicone?) to the inside of the cover. The other two are not sealed and I actually placed them so that they are outside the cover when installed. Doesn't seem to make a difference in performance. Still get the mismatch with actual temperature, but performance is stable. - The temporary and permanent hold features is are nice and easy to use ... particularly as a preventative measure to accomodate those family members you don't want messing around with the programing. - Would be nice if these lit up when a button is pressed. Would be much easier to read. Not a showstopper.

The Honeywell Home RTH221B1039 is a solid, no-frills thermostat that does exactly what it’s supposed to do. It’s easy to install, user-friendly, and provides accurate temperature control. The display is clear, and the buttons are intuitive to use. Perfect for anyone looking for a budget-friendly option that gets the job done without unnecessary features. Highly recommend for basic heating and cooling needs!

the installation instructions are useless, terminals W & R for 2wire gas central heating systems.

Estoy seguro que el termostato funciona perfectamente, pero yo no lo he conseguido. Además las instrucciones están en español y la programación cierto es que es muy sencilla. Mi aparato es Carrier, consulte las configuraciones tanto en Carrier como en Honeywell, pensando que era compatible con Carrier. He probado todas las combinaciones de cables posibles y no lo he conseguido. Probablemente sea culpa mía, solamente quiero decir a otros compradores que se aseguren de la compatibilidad antes de comprarlo. Muchas gracias.

Todo muy bien clima central funciona excelente

Works much better than the old thermostat I had - very happy & easy to install