A Buyer's Guide To Heaters: 120V vs. 240V

Winter is approaching, so it's time to start thinking about updating the electric heaters in your home or business. Whether you are updating one or two heaters in your home, or you are renovating a commercial space and installing new heat options, you will need to know how much voltage, amperage, and wattage the circuit can handle.

Stelpro Heaters

Where Can I Locate The Voltage Of My Existing Heater?

You can find the voltage of your heater on the product's label. If you are not able to locate the voltage from the product label, you can check the circuit breaker to figure out the voltage.

Cadet label

To determine what your space can handle, start by examining your electrical breaker panel. Electrical circuit breakers should have amperage marked on the toggle handle or on the top part of the module. Generally, a 240-volt circuit breaker will have a double pole due to the large supply of energy that is needed to power the heater. A 120-volt will normally have a single pole.

Single Pole Circuit Breaker,Double Pole Circuit Breaker

(Single Pole (left) vs. Double Pole (right) Circuit Breaker)

Volts ACSize of Breaker or FuseWire SizeMax. Wattage Allowed
120V20 AMP Single Pole12/2 Ground1920
240V20 AMP Double Pole12/2 Ground3840
240V30 AMP Double Pole10/2 Ground5760

What If My Breaker Doesn't Look Like The Pictures Above?

That's not a problem! Some circuit breakers will look a little different. In those cases, you will need to use a voltmeter to test the power coming to the heater. This will require caution, if doing it yourself, because you'll be testing live wires. It is suggested that you contact a licensed electrician when dealing with hazardous electrical wires.

You should never assume that you know the voltage amount without checking. Hooking up the wrong voltage heater can be dangerous! If you are unfamiliar or uncomfortable with electrical wiring, please contact a qualifie technician or licensed electrician.

120V or 240V Electric Heater?

If you are replacing your current heater with a new one, you want to make sure to match the power supply that you already have, If you are adding a new heater, 240 voltage heaters are recommended, because they have the capability to support more wattage.

However, hooking up the wrong voltage heater to the wrong circuit will cause you to only receive 25% of the wattage it was designed to deliver.

Recommended Reading

Heaters come in a variety of options and sizes, so how do you find the right one for your space? Read our guide to learn the differences between each type of eater and the proper applications for each.

With the increasing popularity of wall fan heaters, we encourage you to take a look at our Employee's Choice the Cadet Energy Plus Wall Heater! This heater features the perfect size for bedrooms, home offices, and guest rooms.

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.

Baseboard heaters make a great alternative to a central heating system. Read our guide to explore the different types of baseboard heaters and their applications.

Shakir Williams
Shakir Williams

A true creative with a penchant for the spiritual and natural order. She loves the Earth, almost as much as she loves writing about it.

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