Honeywell Home RLV3120A1005 Digital Non-Programmable Thermostat for Electric Heat Only

The Honewell RLV3120A1005/H is an extremely simple thermostat for two wire baseboard heaters. You set the temperature, and it holds it there until you decide to come back and change it again. I’m replacing an old Swan manual thermostat from the 60’s. It was a simple On/Off thermostat which worked off an expanding piece of metal. Accuracy was not its strong point as my room went from feeling like Antarctica to Guam in less than a half hour if I tried to set it to a measly 70 degrees. The heater was either on full blast or turned off. This made my room feel very stuffy and overly warm. There’s probably a reason for that but I’m no heating expert. I would have liked to get a programmable model but I didn’t want to spend too much (I’m renting the house from the college after all) so I settled on the Honeywell. Looked to do all I needed it to anyway. The thermostat feels pretty substantial. Upon opening it up you’ll find a large heat sync and some beefy circuitry to handle the baseboard heater. It’s rated for 1000 watts at 120 volts and 2000 watts at 240 volts. That’s a roughly 7 to 9-foot heater. The exterior plastic feels solid too. The buttons are very clicky but don’t have a very satisfying travel. Installing was a piece of cake. It has black two wires coming out the back, roughly 4-5 inches long which you connect to the baseboard heater wires in your wall. Color and order don’t matter. The box includes wire nuts for securing your connection and two screws for attaching the device to the wall. After killing the breaker (always cut the power to your heater before installing these things) I wrapped the wires together, used the nuts to secure the connection, carefully replaced them into the wall box, and screwed the thermostat in. The screws that come with the thermostat are very long and didn’t fit my wall box so I used the ones that secured the previous thermostat. Once it was secured to my wall, I slipped the top plate over the thermostat and switched the power back on. Worked like a charm. Operation is stupid simple. The display always shows the ambient temperature. Clicking the up or down keys once shows the temperature setting. Clicking them again changes the setting to the desired temperature. Clicking both keys at once brings up a setting to change from Celsius to Fahrenheit. When the heater is on the thermostat will display 1-5 little flame icons. The thermostat will throttle the heater to keep energy use to a minimum and make sure your room doesn’t get turned into an oven for the sake of a single degree. The flame icons indicate how intense the heater is running with five being blazing hot and one being warm to the touch. This throttling works great and the temperature is kept within around +/- 1 degree most of the time. When on full intensity, the thermostat can get a little warm to the touch (guess that’s why it has a heat sync), but not enough to worry about. Pros and Cons! Pros: • Super easy to use • Setup is super easy, just two wires! • Display is easy to read and clear. No noticeable fade from different angles. • Runs heater at optimal intensity for smooth heating and lower power bills • Stays accurate to setting • Does not click when turning on or off Cons: • Buttons are plastic and don’t feel all that great to press (nitpicking, they are fine) • Buttons on my unit feel slanted to the left. They are tilted away from you with a noticeable angle that you can feel when you press them. Weird design choice in my opinion so maybe it’s a defect? (Also nitpicking, they are fine) • There is pretty much no other functionality other than adjusting the set temperature (which is fine because that’s what it is) • The screws were very long and didn’t fit in my wall box so I had to use the screws from my old thermostat. Not a huge deal either but a little annoying. My heater is a simple 7 foot two wire electric baseboard heater with no forced air. Overall, this is a fantastic unit. If you are looking for a simple thermostat to run your baseboard heater then pick up the Honeywell RLV3120A1005/H

So far so good, our old school resistor knob thermostats kept going bad (wouldn’t shut off our baseboard heaters), which would seem very dangerous as they got really hot. This is my first time trying a digital one and so far it really turns on/off (shown on screen as well), to keep it at your desired temperature. Note the default was set in Celsius units! Press and hold both up/down buttons together for 3 sec, then press either up/down, then hold both buttons again for 1 sec to save unit of choice.

Great product, this thermostat is easy to install, provides more more even heat and may save some electricity. The only drawback is the display can be hard to read. it should have some kind of lighting for a few seconds when you push a button. I purchased some of these a few years ago as part of some renovations, and bought these to convert the rest of my thermostats. One thing to be aware of is it can't be used with electric heat with a built in fan, like a bathroom ceiling heater.

Replacing mechanical thermostats for radiant heat ceilings, and couldn’t be happier! Simple installation and does an amazing job of keeping the room temperature consistent. It’s also a big upgrade since it also shows the room temperature.

The specs on this thermostat were not honest in leaving out that it gives temperature ONLY in CELSIUS. It definitely should be included in the tech listing and also next to the item at the beginning of the information about the item. I live in Virginia in the USA. I do not need Celsius. I need Fahrenheit. We did not find that it was Celsius until we turned the electricity back on. The numbers were definitely in Celsius, not in Fahrenheit that we had expected. If this item is available on Amazon in both Celsius and Fahrenheit, there should be a place to check which one you want when you are getting ready to purchase it. We have gone through a lot of trouble trying to find one to replace it. All of the same item at Lowes have the Celsius picture on the front of the box, not a 72F picture. My husband let the Customer Service Department know that all of their boxes of this item are most likely in Celsius. If you do purchase this item, please look at the front of the box carefully to see which temperature is shown, 21C or 72F. I did look at the box, but I had no idea that Amazon would send us an item that was in Celsius instead of Fahrenheit. Amazon, please fix this on this site so that everyone is aware that it is in Celsius, unless you really do have some that are in Fahrenheit. In that case, give the purchaser the choice of C or F when the purchase is being decided on. Thank you for fixing this awful problem!

This thermostat is not for wall heaters!!!! These are highly accurate sensitive thermostats that actually "throttle" the electrical output to the heater so it isn't full on or off to help keep the room at a very constant temperature! They work amazingly well!!!!!! I think there are 5 heating levels. Best unit I have ever used! They are meant to control one heater only. If you have the need to control more then one heater connected to a single thermostat, there is another made by Honeywell for that purpose and it works the same way as well, plus it is lighted. They really need to describe these units better! Many are returned because people buy them for wall heaters, and they will not work for that due to the fan motor.

This unit generally works well. It seems to use a PID control loop, rather than a hysteretic comparator, for controlling temperature; which means it is always modulating the current though the heater and there is no audible on/off relay click. It's 2-wire setup makes it easy to install. My main problem is that the display is not back-lit and the LCD contrast is low. In my mounting location and under normal room lighting, I can't read the display without a flashlight. I don't happen to set this thermostat very often, but this still seems like an oversight.

No tiene muy buen control, no mantiene bien la temperatura. Si lo dejas en cierta zona, prende y apaga constantemente. O lo dejas todo el tiempo encendido o todo el tiempo apagado. Pero le cuesta demasiado mantener una temperatura.

Conforme au descriptif et livraison dans les délais annoncés

Bought this to replace a broken thermostat. So far, it seems to be working perfectly. Easy to install and no fuss trying to figure out how to use it.

Purchased six of these units to replace old two-wire baseboard thermostats. They are very accurate, within 0.5°C of my digital thermometer. Unlike the older thermostats they replaced, they aim to keep a constant temperature, instead of letting the temperature drop too much then blast on. I installed them with Wago 221-412 connectors to speed up the installation. For my application, the only downside is the lack of LCD backlighting (for night time). Very satisfied with my purchase.

This thermostat is easy to install and it does the job. As described, it is not programmable and has no backlight, but it works fine. Keep in mind this is rated 2000W at 240V which means it might not be compatible with a large baseboard. Be sure to check your baseboard's watts rating before purchasing this. If you have a small room with an analog thermostat, this product gives you a good opportunity to replace it for cheap, especially if you catch it on sale, which I did.