Buy Honeywell RTH221B Basic Programmable Thermostat

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My wife and I are both retired so every day is a 'weekend day'. Most thermostats require multiple settings for different kinds of days. Good idea if you're a worker but bad idea if you're me since going on vacation etc requires MULTIPLE thermostat adjustments. Also, why pay extra for annoying unused features. This thermostat is simple, easy to install and has typical Honeywell accuracy and reliability. For me it's ideal.

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Basic programable t-stat. Works well, easy to install Honeywell is a good brand. **HOWEVER in picture on amazon the screen on it looks back-lit, but it is not lit.

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I bought this thermostat this fall from a big box home improvement store and it's paid for itself several times over in a few short months (and I paid more than the listing price on Amazon).

I had never installed a thermostat before, but it was a breeze to install. I turned off the breakers to my living room, carefully removed the old thermostat, attached two wires, installed a couple of screws (I think that I ended up drilling one new hole), and turned the power back on. Less than 15 minutes from start to finish, and I'm not the handiest gal you'll ever meet. It worked. I set it to turn down at night while we're sleeping and during the day when we're gone. I also put the plastic on the windows, but other than the new thermostat I did nothing different this year than last.

February 2008the portion of our utility bill for natural gas was $188.03. February 2009, with the average temperature just 4 degrees warmer, our natural gas bill was $88.08. We have saved at least $40 every month since I installed it. It's paid for itself several times over. It's probably the best thing I've purchased in a very long time.

Honest reviews on Honeywell RTH221B Basic Programmable Thermostat

I can't believe I waited so long to replace the old mercury bubble thermostat on my hot water heat system. I noticed a friend had a new one, so I decided it was time to do some research here at Amazon.

I wanted a vertical style to match the placement of the old one which narrowed the field considerably. I wanted a simple day/night setback and didn't need separate settings for weekends. I wanted simple controls and ease of temporary adjustment. This one fit the bill perfectly.

Installation was a breeze. The instructions are clear and easy to follow. My two-wire system connected to the Rh (Red heat) and W (White) terminals. The wires weren't that color (probably the original 90 year old wires!) so I either guessed right or, more likely, it would have worked if they were reversed since it's simply an open/close switch to activate the heater. I even reused the mounting screws from the old unit sweet! Stop by your local Dollar Store and pick up a mini screwdriver set if you don't have one.

Programming is straightforward, and again the instructions are clear. It comes preprogrammed with four periods Wake, Leave, Return, and Sleep. It's easy to adjust these to your desired time/temp. I skipped two of them completely by simply pressing the Hold button for four seconds while that period was displayed during setup. Believe me, you'll be tweaking your settings with abandon after the first run-through... it's that easy.

I love the simplicity of the display. What's the current temp? Look at the screen. You're a bit cold? Tap the up arrow once and read the setpoint; tap it again to temporarily raise the setpoint one degree, again for two degrees, etc. The unit will retain your temporary setting until the next programed change (e.g. night setback) or until you press the Run button. Going away for a couple of days? Tap in the desired setpoint and press Hold. Simply press Run again when you get home. As noted in other reviews, there is no backlight in the display.

You can download the installation and user's manual at the Honeywell website to get a peek at how it works.

Be sure to note the Configuration Menu in the installation instructions. I had to change the "Heating Cycles per Hour" setting to "3" (for my hot water system) from the default "5" setting.

What is Heating Cycles per Hour, you ask? It's a means to fine-tune the efficiency of the system's attempts to maintain your desired temperature. It's ONLY active when you're within a degree or so of the setpoint temperature. Here's how it works:

Say, your setpoint temperature is 70°. As the heater brings the room air temp up towards the setpoint, an anticipator circuit cuts off the heat at a predetermined value, say 69° to keep from overshooting your requested 70°. Ideally, the residual heat from your burner/blower/fan/radiator will gently nudge the air temp up to 70°, and all is right with the world. So far we have: temp below 69°, run heater; temp above 70°, stop heater. But what happens between 69° and 70°? What if there wasn't enough residual heat to get to 70°? Or what if your furnace isn't sized properly, or your insulation is weak, or the kids left a window open? Where's that 70° you requested?

This is where you heater starts cycling. My "Cycles per Hour" is set to 3, which means 3 twenty minute cycles each hour consisting of 10 minutes OFF, 10 minutes ON. When the air temp hit 69° the heater stopped for 10 minutes, hoping the air temp will reach the magic 70°. 10 minutes later it takes a peek at the temp... 70° or above? Great! Job done. No cycling involved. Oops only 69.3°? start up again for 10 minutes, shut down, wait 10 minutes and check again. 69.8° this time? Start up again for 10 minutes and another cycle. This time, let's say the temp hit 70° after 8 minutes of heat. Great! job done, shut off heat and stop cycling. It might overshoot to about 70.3° this time well within your comfort zone. Now, sit warm and cozy in front of the TV as the temp slowly falls from 70.3° to 69° and listen for the cycling to begin again. If you're well insulated, it's a fairly mild night, and your heater is sized properly, it might go through a cycle every couple of hours. If there's a blizzard blowing outside your poorly insulated shack, it might cycle on and off every 10 minutes, or even stay on constantly if it can't get you above 69°.

To recap: Temp below setpoint minus one: heater ON. Temp above setpoint: heater OFF. In between: cycle ON and OFF in attempt to efficiently get to setpoint without too much overshoot. Why? A heater is more efficient running longer cycles rather than rapid On/Off cycles. A heater with a lot of "thermal inertia" like my hot water system, takes a while for those warm radiators to gently get the air temperature to the desired setpoint... it needs cycles a bit longer to be efficient and effective. A rapid heat system, like an electric wall heater, will get that air temp up quickly it needs a higher cycle rate / shorter 'burn' time to stay efficient and avoid overshoots. In fact, the cycle rate for electric heat is 9: that's 9 cycles of 6.7 minutes per hour.

Air conditioning cycle/hour is fixed at 3.

One more thing: if you want the fancier model, the Honeywell TH2110D1009 is the same unit, but with backlight, 5/2 day programming, and something called "Adaptive Intelligent Recovery" which learns how fast your heater gets you to your desired temperature so that you can program it to BE at a given temperature at a given time... handy for those early morning middle-of-winter wake ups!

Be sure to properly dispose of that mercury!

Enjoy!

Find helpful customer reviews and review ratings for Honeywell RTH221B Basic Programmable Thermostat

I bought 2 of these units. After letting them sit on the table next to each other for a while, they displayed different temperatures, by a difference of about 3 degrees. I was surprised they were that different. I considered sending them back, but instead I used them as they were. The temperature difference seems to have worked its self out and they do their job just fine. After using one of the Lux models a few years ago, I found myself wanting the extra features that it had (another mode for weekends). The display constantly shows the current temperature but unless you hit one of the up/down buttons, will not show you what the current thermostat temperature is set to. I found this annoying as my wife is constantly changing the temp on me and I would like to know what it is currently set at. The LUX model displayed both. If I had it to do over again I would have bought a different brand, probably Lux. Also, a horizontal model would have covered the round marking that my previous thermostat left.