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If you’re looking to voice control or remotely control your electric baseboard, ceiling, in-floor or fan heating system, then a smart line voltage thermostat is worth considering.

Not only can you integrate line voltage smart thermostats with other smart devices, you can also save money by using eco-modes and geofencing features. That way, your heating system goes into hibernation when you are out of your home.

Let’s get started.

Best Line Voltage Smart Thermostats
9.7 Empowered Homes
TOP PICKAlexa, Google Assistant, and Siri voice control
9.5 STELPRO
BEST Z-WAVE PICKSingle-pole and double-pole configurations
9.4 Nuheat
7-day programmable schedule
9.2 STELPRO
BEST ZIGBEE PICKCan be connected via Wi-Fi as well as Zigbee
8.8 Sinope
Smart hub integrations (e.g. SmartThings and Hubitat)
8.7 STELPRO
BEST BUDGET PICKCompatible with Zigbee devices

What is a Line Voltage Thermostat?

Line voltage thermostats are also known as high voltage or inline thermostats and are used with electric-powered heating systems. They are also commonly referred to as 120 volts or 240 volts thermostats, 2 wire or 4 wire thermostats, and single-pole or double-pole thermostats.

Before we proceed, it’s important that you check if the line voltage thermostat will work with your heating system or not. A line voltage thermostat should work with the following types of heating systems:

  • Baseboard Heaters
  • Ceiling Heaters
  • In-Floor Heating
  • Forced Fan Heaters

If you have one of these heating systems, line voltage thermostats will most likely work for you.

What are the differences between Line Voltage and Low Voltage thermostats?

One of the main differences between line voltage thermostats and low voltage thermostats is that the former utilizes direct mains voltage as a means of powering the heater whereas the latter uses the burning of fuels for power.

Another major difference is that low voltage thermostats typically run on 24 volts whereas line voltage thermostats run on high voltage (120 or 240 volts).

Low voltage thermostats are mostly used for central heating systems, while line voltage thermostats work well with electric baseboard heaters, ceiling heaters, in-floor heaters, and forced fan heaters.

Single Pole vs. Double Pole Thermostats

When it comes to line voltage thermostats, there are two varieties available on the market: single-pole and double-pole. 

A simple way to determine the type of line voltage thermostat you need is to check the back panel of your existing thermostat. If there are two wires on the back, then it is a single-pole thermostat, and if there are 4 wires on the back, then it is a double-pole thermostat.

At SmartHomePerfected, we always advise readers not to undertake any work they are not competent in performing and if in any doubt, it is best to seek the assistance of a professional.

Differences

Let’s discuss the type of thermostat you should buy for your home. The basic difference between a single-pole thermostat and a double-pole thermostat is that a single-pole thermostat can’t be turned off. In contrast, the double-pole thermostat comes with the “off” functionality.

So, if you choose a single-pole thermostat, then your heating system can’t be turned off through the thermostat, and it will run on a low setting. You can only turn it off by completely shutting down the heating system.

On the other hand, if you opt for a double-pole thermostat, you will get the option to completely turn off your heating system.

In the end, the choice will likely depend on the wiring that you already have in place. If you want to turn off your heating system via thermostat, then the double-pole is the best option. If you have no problem with turning off the heating system completely, then you can go with a single-pole thermostat.

9.7
TOP PICK
Alexa, Google Assistant, and Siri voice control

The Mysa Smart Thermostat is a powerful line voltage thermostat that comes with a sleek design and a variety of integration options.

Top Features
  • Works well with Alexa, Google Assistant, and Apple HomeKit.
  • Minimalistic and sleek design.
  • Easy to set up.

Mysa Smart Thermostat is one of the best line voltage smart thermostats on the market. It comes with a modern and minimalist design, which makes it easy for it to blend into any environment.

On top of that, the Mysa Smart Thermostat also works well with most smart home systems such as Alexa, Google Assistant, and the Apple HomeKit.

A good thing about the Mysa thermostat is that it comes with extensive online guides and video guides, which make it easier to set it up. So, if you have any experience in DIY, then you can install it in 15-20 minutes. However, if you are not experienced, then we would recommend asking an electrician to service it.

The Mysa Smart Thermostat also works with IFTTT, which means that you can easily program the various actions. It also uses your location to determine if anyone is in the home, and then it takes measures to save energy. Also, it comes with vacation mode, which you can enable when you go on holiday to cut down on energy costs. If you are looking for a capable line voltage thermostat, then you can’t go wrong with the Mysa Smart Thermostat.

What I liked
  • It comes with extensive guides, which make it easier to set up.
  • Price is quite reasonable.
  • Comes with a minimalistic look, which makes it easier to blend with most interiors.
  • It supports IFTTT, which you can use to define different actions and their trigger points.
  • Premium look and design.
What I didn't like
  • It won’t reconnect automatically after a power outage, so you will have to reset it manually.
9.5
BEST Z-WAVE PICK
Single-pole and double-pole configurations

The Stelpro Ki Smart Thermostat is a very efficient thermostat that works well with Z-Wave devices and hubs.

Top Features
  • It works flawlessly with Z-wave devices.
  • It comes with Eco mode, which saves a lot of energy.
  • Comes in single-pole and double-pole configurations.

The Stelpro Ki Smart Thermostat is a very capable thermostat, with all the bells and whistles which you can expect from a good smart thermostat.

For starters, it’s compatible with Z-Wave devices, and you can easily link it to a Z-Wave-enabled hub in your smart home. On top of that, it also comes with an Eco mode, which helps you save energy.

The best thing about the Stelpro Ki Smart Thermostat is that if you connect it with smoke and carbon monoxide detectors, it can automatically turn on a connected HVAC system to extract harmful gases from your home, if detected. Similarly, you can also use it with your door- and motion sensors, and it will adjust the temperature automatically.

The Stelpro Ki Smart Thermostat comes with a minimalistic design, which makes it easier to blend into any environment. You also get the option to pick a single-pole or double-pole thermostat version, which is a big plus. 

Overall, the Stelpro Ki Smart Thermostat is a great smart thermostat, and if you have Z-wave products in your smart home, then it’s a great option for you.

What I liked
  • Compatibility with Z-wave devices.
  • Eco Mode to save energy.
  • Variable heating with 4 different levels of power.
What I didn't like
  • Some customers complained about the quality of technical support.

The nVent Nuheat Signature Thermostat is a programmable thermostat which comes with top of the line features and GFCI protection.

Top Features
  • It can be programmed according to a 7-day schedule.
  • GFCI protection protects against the risk of electrocution.
  • Comes with a built-in display to show all the important information.

The nVent Nuheat Signature Thermostat is a premium smart thermostat that comes with some great features. The main highlight of this thermostat is that it comes with Class A GFCI (Ground Fault Circuit Interrupter) protection. This feature comes into force when it detects current leakage, and it protects users from the risk of electrocution.

Another great feature of the nVent Nuheat Signature Thermostat is that it’s programmable, and you can configure the thermostat based on a 7-day schedule. 

At the same time, it’s also compatible with IFTTT, which allows you to integrate with other smart devices and set actions or triggers for different conditions. It’s also compatible with Wi-Fi, and you can use the web portal or the smartphone apps to control the thermostat.

What I liked
  • It integrates with Amazon Alexa, Google Assistant, and IFTTT.
  • It protects you from the risks of electrocution with GFCI protection.
What I didn't like
  • More expensive than competitors.
  • Some users complained about the web portal’s user interface.
  • It does not automatically reconnect to Wi-Fi if there is a connection drop.
9.2
BEST ZIGBEE PICK
Can be connected via Wi-Fi as well as Zigbee

The Stelpro Maestro Controller Thermostat is a versatile thermostat that works with Wi-Fi as well as Zigbee.

Top Features
  • It works well with Google Assistant and Amazon Alexa via IFTTT.
  • It allows you to control heat in up to 8 zones.
  • It can be connected via Wi-Fi as well as Zigbee.

The Stelpro Maestro Controller Thermostat comes with Zigbee and Wi-Fi connectivity options, which means you can easily integrate it into your smart home. 

It also comes with support for IFTTT, which allows you to connect the thermostat with Google Assistant and Amazon Alexa. 

The Stelpro Maestro Controller Thermostat also comes with an app that offers you many great features. You can use the app to set up different zones and manage your heating using it. It also comes with a geofencing feature which allows the thermostat to adjust the heating when you enter or leave your home. 

The app also provides extensive reports on energy consumption, so that you know how much energy is being used, and you can use it to make informed decisions.

What I liked
  • Comes with a built-in display.
  • The geofencing feature can help you save a lot of energy.
  • It works with IFTTT, which you can use to automate many actions.
  • It can support up to 19 Stelpro Thermostats across your home.
What I didn't like
  • Some users have complained that the thermostat can give false ambient temperature readings in certain conditions.
8.8
Smart hub integrations (e.g. SmartThings and Hubitat)

TheSinope Smart Thermostat is an affordable line voltage thermostat that works well with Amazon Alexa and most major smart hubs.

Top Features
  • It comes with a geofencing feature that adjusts the temperature based on your presence.
  • It works well with Amazon Alexa, Google Home, Neviweb, SmartThings, and Hubitat.
  • It comes with a built-in display.

The Sinope Smart Thermostat (TH1123ZB) is one of the best high voltage thermostats on the market, and it works on 240 Volts.

The thermostat comes with great compatibility, and it works well with Amazon Alexa, Google Home, Samsung SmartThings, and Hubitat. However, it requires the Sinope GT130 Hub for integrating, which has to be bought separately.

The thermostat comes with a small built-in display where you can see details such as temperature and time.

You can also install the Neviweb app, which unlocks some additional features which you can use. You can use the app to set actions according to a schedule. Similarly, you can also enable the geofencing option and set an array of actions to trigger when you enter or leave the home. 

The app also generates detailed energy reports, which will help you know about overall energy consumption, and you can take measures to control it.

What I liked
  • Easy to set up with step-by-step guides.
  • It’s compatible with popular digital assistants such as Google Assistant and Amazon Alexa.
  • It comes with an app that offers many useful features.
  • It provides real-time energy reports in the form of graphs.
What I didn't like
  • It requires a hub to function.
  • The display is quite small.

The King Hoot is a programmable line voltage smart thermostat that comes with accurate temperature control.

Top Features
  • It comes with a built-in LCD display.
  • It features an electronic sensing feature for accurate temperature control.
  • It’s programmable, and you can program it for all 7-days with the app.

The King Hoot Smart Thermostat (K902-B) is a premium line voltage smart thermostat, designed by King Electric, which has been in business for over 60 years.

The King Hoot Smart Thermostat allows you to set different zones in your home, and control heating in the zones directly from the app.

It also comes with accurate sensing technology, which claims to detect accurate temperature with a margin of ±1 degrees Fahrenheit. The device also features over-the-air (OTA) firmware updates so you can expect the thermostat to continually improve.

It is also a programmable thermostat, allowing you to set a heating schedule for up to 7 days. In this way, you won’t have to adjust it every single day. 

It also comes in both single- and double-pole configurations, so you can easily pick the one which suits your requirements best.

If we look at issues, then the biggest problem with King Hoot Smart Thermostat is that it doesn’t come with native support for Amazon Alexa, Google Assistant, or integrating with other smart home devices.

What I liked
  • Comes with multi-zone support.
  • It’s an accurate thermostat and offers the accuracy of ±1 degree Fahrenheit.
  • Comes with over-the-air (OTA) software updates.
What I didn't like
  • Doesn’t work with Google Assistant, Amazon Alexa, or Apple HomeKit.
  • It’s expensive compared to other smart thermostats.
8.7
BEST BUDGET PICK
Compatible with Zigbee devices

The Stelpro ASMT402 Maestro is a very capable line voltage smart thermostat that offers great value for money.

Top Features
  • It comes with a built-in display.
  • It offers accurate ambient temperature control with a margin of ± 1 fahrenheit.
  • It’s compatible with Zigbee devices.

The Stelpro ASMT402 Maestro is a very efficient line voltage smart thermostat that you can use to regulate the heating system in your home.

It’s mainly designed to be used with the Maestro ASMC402 Controller thermostat, and when it is connected to it, it can save up to 25% of energy. You can also link it with any Zigbee-compatible controller as well.

It’s the best option for you if you are planning on using multiple thermostats in your home. Then you can simply use the Maestro ASMC402 Controller thermostat as the main thermostat and link the Stelpro ASMT402 Maestro thermostat to it.

What I liked
  • It offers excellent value for money.
  • It can be connected to the Maestro ASMC402 Controller thermostat, and it can save up to 25% energy when connected.
  • It’s also fully compatible with Samsung SmartThings.
What I didn't like
  • The built-in display is relatively small.
  • It offers additional features only when connected with the Maestro controller thermostat or a Zigbee hub.

Should I Buy a Line Voltage Smart Thermostat?

Financial Savings

One of the main reasons why you should invest in a good smart thermostat is financial savings. A smart thermostat will allow you to automate the process and choose different settings, which will save a lot of energy and, consequently, energy costs, in the long run.

Remote Control

Smart thermostats can also be controlled remotely, so you can take action when away from your home. For example, if you are in your office, you can turn on the heating remotely, and by the time you reach home, you will have a cozy environment where you can relax.

Voice Control

Most smart thermostats also work well with major voice assistants such as Google Assistant and Amazon Alexa. You can use different voice commands to control thermostats.

Smart Integration

If you have a smart home, then you can integrate smart thermostats with other products to automate it. For example, you can integrate a thermostat with motion sensors, and you can set different actions such as when you enter the home, the thermostat will turn the heating on for you.

Granular Settings per Zone

Smart thermostats also allow you to set different zones in your home, and you can configure settings for each zone. For example, you can set a different zone for your bedroom, and specify a custom temperature for that room. Similarly, you can set the custom temperature and settings for the living room and so on.

Common Questions Relating to Line Voltage Smart Thermostats

Can a Line Voltage Thermostat control my air conditioning?

No, a line voltage thermostat cannot control air conditioning. You will need a specific low voltage thermostat for controlling your air conditioning unit.

Can I use the Nest thermostat to control my baseboard heater?

The Nest thermostat is a low voltage thermostat, so you cannot use it to control your baseboard heater. Nest thermostats usually work on systems that use 36 volts while baseboard heaters usually work on 120/240 volts. So, you will need to get a line voltage thermostat to control your baseboard heater.

The Verdict

Line Voltage Thermostats are useful devices that can not only save a lot of energy but also make it easier for you to control the heating system itself.

When it comes to the best line voltage smart thermostat, the Mysa Smart Thermostat thermostat is our number one recommendation because of its great features. The Stelpro Ki Thermostat is also a great option, but it comes with limited features. 

Now you tell us which thermostat looks most promising to you? Let us know your answer in the comment section below.

9.7
TOP PICK
Alexa, Google Assistant, and Siri voice control

The Mysa Smart Thermostat is a powerful line voltage thermostat that comes with a sleek design and a variety of integration options.

Top Features
  • Works well with Alexa, Google Assistant, and Apple HomeKit.
  • Minimalistic and sleek design.
  • Easy to set up.

Sources

www.homelectrical.com

Show CommentsClose Comments

2 Comments

  • George
    Posted December 13, 2021 at 10:38 pm

    I live in an area where blackouts are very common. What high voltage thermostat should I get that will still work and reset itself after the power goes out? I’d like to be able to control the heat remotely but that’s not hugely important.

  • Wayne M
    Posted September 16, 2020 at 1:45 pm

    You say: “So, if you choose a single pole thermostat, then your heating system can’t be turned off through the thermostat, and it will run on a low setting. You can only turn it off by completely shutting down the heating system.”

    A single pole thermostat does not completely disconnect the heater, but it does turn it off. It does not run on a low setting.

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