Picture of the Honeywell 5-2 Thermostat RLV310A, Mounted and Operating.

Honeywell RLV310A Digital Baseboard Heat Thermostat Review

We purchased two of the  Honeywell RLV310A Digital Thermostat   for the electric baseboard heaters used around my home.

At a cost of approximately $30 from Lowe’s home improvement center, the price seemed reasonable.

Picture of the Honeywell 5-2 Thermostat RLV310A, Mounted and Operating.
Honeywell 5-2 Thermostat RLV310A, Mounted and Operating

The RLV310A Honeywell line voltage thermostat is much quieter (no clicking sounds as it turns the heaters on and off), as it utilizes an all-electronic switching mechanism (a triac) to switch on and off the 220 volt supply to our 2500 watt resistance baseboard heaters. Below sums up our experiences with this modern day manual yet digital thermostat.

Benefits, Features, Advantages, and Pros of the Honeywell RLV310A Digital Baseboard Heat Thermostat 

Honeywell’s supplied installation instructions were easy to follow and straight forward.

Installation took under a half hour and required only a Philips screwdriver since I was just replacing an existing thermostat instead of installing a new one from scratch.  Warning: Since this thermostat controls the line voltage supply to the heater, if power to the circuit is not shut off, the installer could receive a severe 220-volt shock.  This is not a low-voltage model, so treat it with respect, and observe, to-the-tee, all warnings, cautions, and installation procedures as laid out in the included documentation.

The RLV310A has just two black wires (single pole switching) that you hook up as you would a regular light switch into one side of the electric heater supply line.

No ground terminal is provided, as this thermostat is packaged in an all-plastic case; including its mounting plate. This further simplifies installation.

Since there were no programming instructions included, as this digital thermostat is not programmable, the operating instructions are thus, quite simple, short, and easy to understand.  Though digital, this is strictly a manually operated thermostat.

With just two buttons (to raise and lower the room temperature set point), the RLV310A is quite simple to operate.  It’s temperature readout is digital; not a dial.

It responds immediately when you change the temperature set point, and immediately turns on the heater full blast when you raise the temperature, and turns it completely off when you lower the temperature, until the room temperature falls to the new set point.

In terms of comfort, we appreciated the tight temperature control of this unit, as it allows no more than a plus or minus 0.35 degree temperature swing in the room, before actuating the heater (turning it on or off).  Of course, this means that the heaters cycle on and off quite a bit more often than they did with the mechanical bi-metal thermostats we’d been using prior.  However, with other noises in the room, you don’t really hear this cycling, particularly since the electronic switching herein is totally quiet — no clicks.

As this thermostat limits the size of the temperature swings in the room, the user’s guide says that savings in heating bills should be significant. This is important when paying for electric baseboard heating, as each room costs a few dollars per day to keep warm as it is.  We did not notice much energy savings.  But comfort levels in the heated rooms definitely improved markedly.

It never gets stuck in the on or off position.  The big reason we ended up replacing the mechanical temperature sensors with this one, was that they’d occasionally get stuck, ON, and the room temperature would skyrocket to 85 degrees in almost no time.  This happened due to those mechanical micro switches binding up with the bi-metal sensor material.  But, since the RLV310a likely uses a thermistor to detect room temperature, and a microprocessor to interpret the readings and then electronically control the heaters, it never sticks that we’ve seen.

Disadvantages of The Honeywell RLV310A Digital Thermostat

This automatic thermostat is not at least a little programmable. It would have been nice to be able to adjust the span between the turn-on and turn-off temperatures — the temperature differential.

It offers a very narrow yet non adjustable temperature span of approximately 0.7 degrees total. That is, when the room temperature falls 0.35 degrees below the set point temperature, this Honeywell digital thermostat turns the heater it controls on. Then, when the temperature rises to 0.35 degrees above the set point, this thermostat turns the heater off. Thus, the heater comes on and off several times per minute, which can be distracting when all else in the room is quiet.  But as mentioned, with quiet baseboard heaters, you don’t even notice this frequent switching action.

Our particular heaters hum, ping, and clank each time they’re activated. So while we may have eliminated the clicking noises from the old electro-mechanical thermostats by replacing them with this one, we have exacerbated the noise problem from the heaters themselves. Beware of this if you decide to upgrade to a digital thermostat. This unit would likely work best with those virtually silent hydronic electric heaters.

As is true with so many consumer electronics devices these days, no audio indication is given when the UP and DOWN temperature buttons are pressed, which can complicate use by the blind and vision impaired population. However, since these controls are the only two to operate, the absence of sound when pressing them is no big deal.

The temperature display does not light up, so it cannot be viewed without turning on another light in the room.

Our Rating

Overall, though it’s non programmable, we’re quite pleased with this electronic thermostat. The unit works exactly as described in the accompanying operation manual, and has revealed that we have very noisy heaters. This just may be the excuse we need, to upgrade the cheap baseboard heaters to the quieter hydronic units we’ve seen at the stores.  We’d rate this Honeywell product at 93 out of 100.  It brings the precision of digital operation to the easily worked manual line voltage thermostat market.

Where to Buy the Honeywell RLV310A Digital Thermostat

You can find this product at Radio Shaci, Lowe’s, Home Depot, and other home improvement and electronics centers.

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Revision History

  • 2017-03-11: Revised the tags list.
  • 2015-12-13: Added appropriate tags.
  • 2015-01-10: Added picture of mounted and operating RLV310A thermostat.
  • 2014-11-23: Adjusted ad placement, added a References section, and updated the content.
  • 2012-08-25: Original publication.