New! Honeywell Home Programmable Thermostat, Single-Stage, 1 Heat/1 Cool Compatibility, Flexible Schedule, X2P, White, RTH21B
$44.49 Original price was: $44.49.$6.99Current price is: $6.99.







The Honeywell Home X2P Programmable Thermostat is optimized for single-stage 1 heat/1 cool systems. Its flexible scheduling technology allows personalized programming to fit your lifestyle in 5-1-1 day, 5-2 day, 7 day, or 1 week – there’s even a non-programmable option. It’s a quality thermostat for your home that can be customized to receive change air filter reminders, coordinate with home decor thanks to the interchangeable decorative accent pieces (comes with white and gray options), and select display settings.
CUSTOMIZE: Choose to receive change air filter reminders, change out the decorative accent color with interchangeable white and gray accent pieces, and select display settings to optimize this thermostat for home. The RTH21B is a directly replacement the RTH2510, and replacement for the RTH2410 offering personalized programming of 7-day, 5-1-1 day, 5-2 day or 1 week schedule options
SCHEDULE: Personalize programming in 7 day, 5-1-1 day, 5-2 day or 1 week options – there’s even a non-programmable option
EXPERIENCE: A large screen and clear font enhance daily use
INSTALLATION: The Honeywell Home UWP wall plate provides an easy install process and simplifies future device upgrades
FEATURES: Flexible scheduling, backlit display, custom display settings, change filter reminder, extended 32°F low-heat setpoint, 1-year warranty
COMPABILITY: 1 Heat/1 Cool, 750 mV, hot water heat, forced air (gas, oil, or electric) [does not work with electric baseboard heat (120-240V)]
POWER: 2 AA batteries (not included)
8 reviews for New! Honeywell Home Programmable Thermostat, Single-Stage, 1 Heat/1 Cool Compatibility, Flexible Schedule, X2P, White, RTH21B
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Kindle Customer –
Old system new look
Bought this for 2 wire single stage gas boiler / baseboard heat. It replaced an old one that wasn’t programmable (just up or down).Considered lots of smart options but without a common wire they all inevitably run out of juice. Power ‘stealing’ doesn’t really work.This is a perfect solution to modernize heating in my 150 year old MA home.Installation was easy, initial setup was clear with the manual, and setting the program was simple and straightforward.When I first opened the manual I saw “‘C’ wire required” listed and got worried, but it is a shared manual with the WiFi enabled versions. You don’t need a C wire, it works great with just two wires.
John S. –
Honeywell Thermostat Delivers Great Performance and Affordable Price
Easy to connect and install, improves over previous model. When setting up schedule, there’s only one hour and minute setting for both heat and cool, unlike earlier versions which allowed separate settings to be entered.Bonus new feature, the addition of “CIRC” to fan functions “AUTO” and “ON”. CIRC is the intermittent activation of the fan for short periods of time regardless of Heat or Cool, to keep the air circulating. Very useful.Well worth it, very good value for the price.
Fred G. –
Good Thermostat
So far, so good. Easy to install and program. Great instructions for both the installation and programming. It does everything I need it to do. It appears to be of good quality, which is something I would expect from the Honeywell name, but only time will tell.
rainforest –
Good thermostat with some drawbacks
I bought this thermostat to upgrade from our older, simpler one. The advice from reviewers helped me know what I was getting into. Installation was not easy, but I could do it because I am handy and have a drill and all the tools I needed. It took two hours and I was exhausted but successful. I like the ability to override the program and hold the temperature for a trip or absence from home. The program feature, however, is disappointing. I haven’t given up on finding a way to fix it, but so far I’m stuck with the program it comes with. You can’t change the times or temperatures. The bedtime is 10pm, not late enough. I can’t return it because of all the effort I put into installation. The basic thermostat this replaced was also a Honeywell, with fewer features, yet it offered true program flexibility, whereby you could set any on/off time and temperature you wanted.
SP –
Great Unit
Easy to install and easy to program. Works well
Becky –
Thermostat review
Easy to install. I hooked the wires in before attaching to the wall. It was easier. It’s working great! We are warm again! Very happy.
Matt C –
Avoid
I have a Honeywell I wanted to replace so I could run a schedule. Should have been easy. The unit would not turn on the AC no matter what I did. Hired an electrician. He could not get it to work either. Maybe I got a lemon. But I wasn’t about to buy another one. I just put the old one back on there.
Janice W –
Clear, Large display
Clear display even when not backlit. Like to see actual temp and set temp on the display at the same time. User interface is very user friendly. Setup can be a bit tricky if not referring to user manual for the codes and what they refer to, otherwise very easy setup.