Installing a Thermostat for a Baseboard Heater

As your number one source for heating solutions, we understand the importance of a properly installed thermostat. Our step-by-step guide will walk you through the process of installing a single or double pole thermostat for your baseboard heater.

Understanding Thermostats: Single Pole vs. Double Pole

A single pole thermostat is a type of thermostat commonly used for controlling heating and cooling systems. Single pole thermostats have only one electrical connection for controlling the power supply to the heating or cooling equipment.

A double pole thermostat is designed for more complex heating and air conditioning systems. It has two electrical connections, which allows it to control both the heating and cooling functions of the system.

The main difference between the two lies in their functionality:

  • Single pole thermostats consist of two electrical wires. Single pole thermostats, despite lacking an on/off feature, regulate the temperature of your baseboard heater.
  • For more control and flexibility over your heating system, a 2 wire thermostat is the best way to go. A double pole thermostat, equipped with four wires and an off feature, let you completely cut power to your baseboard heater.
Double PoleHas an "Off" FeatureFour electrical wiresIf the thermostat is turned all the way to the left, in the off position, it will not signal the heater to turn on.
Single Pole No "Off" FeatureTwo electrical wires If the thermostat is set to 40 degrees, as soon as the temperature in the room drops below 40 degrees, it will signal the heater to turn on. 

Essential Tools Needed for Installing a Thermostat

To successfully replace thermostats on your 240 volt baseboard heater, your electrician will arrive with a few essential tools:

  1. A flat-head screwdriver, essential for removing the cover plate of your existing thermostat.
  2. Wire cuttersand strippers are used to cut and strip the wires connected to your old thermostat. This prepares them for connection to the new thermostat.
  3. Before starting any electrical work, it is important to make sure that the power to the baseboard heater is turned off. A voltage tester helps your licensed professional verify that there is no electrical current running through the wires.
  4. Pliers come in handy for gripping and twisting the wires together.
  5. Wire nuts are used to join the wires together. Your electrician will ensure that they are the appropriate size for the gauge of your wires.
  6. Once the interior installation is complete, they will use a level to evenly install the thermostat.

Step-by-Step Guide on Wiring a Single or Double Pole Thermostat

Your electrician will make sure to turn off all electrical power from the circuit breaker before installing your thermostat.

Step 1: Remove one of the junction box covers at the end you wish to wire.

Step 2: Disconnect only one factory connector on the side you have open, leaving two loose heater wires.

Step 3: Connect the supply grounding wire to the green grounding screw.

Step 4: If not already present, route supply wire from the circuit breaker to the thermostat wiring box, and then to the heater.

Step 5: In the thermostat wiring box, connect the ground wire coming from the circuit breaker to the ground wire. Your electrician will connect the ground to the thermostat or wiring box, if available.

The next steps will differ depending on which thermostat you are installing.

For Single Pole Thermostats

  1. Connect the hot supply wire to the thermostat wires. Typically, this is marked “L1” or “Line”.
  2. Connect the T1” or “Load” wire to the same color supply wire feeding the baseboard heater.
  3. Connect the white wire to the same color supply wire feeding to the baseboard heater.

For Double Pole Thermostats

  1. Connect the black hot supply wire to the first thermostat wire.
  2. Then, connect the remaining supply wire to the second thermostat wire. Typically, these are marked “L1”and “L2” or “Line”.
  3. Connect the “T1” wire to the black wire leading to the heater. Connect the remaining thermostat wire to the white wire leading to the heater.

Find Single and Double Pole Thermostats at HomElectrical

At HomElectrical, we provide you with the resources you need to make informed decisions about your electrical systems. Check out our wide range of thermostats and other HVAC products to create a space that maximizes comfort. Take control of your heating system and enjoy the benefits of a well-regulated temperature in your space all year round.

Recommended Reading

Before you can heat your space, you need to choose the right kind of heater. Read our guide to learn about the different types of heaters and find the one that works best for you.

When choosing a heater, you need to choose the right voltage: either 120V and 240V. Read our guide to learn the differences between 120V and 240V and how to figure out which one you need.

Elizabeth Cesar
Elizabeth Cesar

Elizabeth is an accomplished graphic artist who enjoys the process of creating and building powerful visual experiences for others. As a content writer for HomElectrical, she turns her creativity into helpful tips and tricks and guides for buyers. In her spare time, she enjoys sightseeing and creating new experiences with her friends.

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