One of the most important things you can do when shopping for a heater, is taking the time to make sure you get one that’s the right voltage for your installation.

Our heaters come in 120, 208 and 240 volt models (although 208 volt models are really just for apartment buildings with elevators). What’s the right voltage for you?

Right voltage for replacement heaters

If you’re replacing an old heater, the new heater needs to be the same voltage as the old heater. The easiest way to find the voltage of your old heater is to check the product label.

CS102 rating label
You can find the voltage listed on product rating labels. This CS102 is rated for 240/208 volts — which means it would be replaced with a 240 volt heater.

This is a really great reason to either keep your old heater until the new one is installed or to snap a photo of the product label. Steve from Tech Support says that a lot of people get rid of old heaters before buying new ones, which means it’ll be a little more complicated to figure out the right voltage.

If you’re not able to figure out the voltage from the product label, you can check the breaker powering the heater.

120 vs 240 volt
In general, a 240 volt breaker will look like the one on the left, while a 120 volt will look like the breaker on the right.

The photo above is a good starting place, but some breakers might not look exactly like the ones above. If you’re not sure on the voltage just by looking at the breaker, you’re going to need to figure it out another way.

You can also use a voltmeter to test the power coming to the heater. Just be extremely careful if you’re going to do this, because you’re going to have to test live wires. It’s dangerous and can easily be done incorrectly. For more info on how to use a voltmeter, please get in touch with our Tech Support team or consult a licensed electrician.

New installations

If you’re installing a new heater, things are a lot easier. We generally recommend you pick up a 240 volt heater and install a new, dedicated 240 volt circuit for the heater.

Never assume

The most important thing, is NEVER ASSUME you know the right voltage. You need to be 100 percent sure that you’re getting the correct voltage.

Honestly, a lot of people we talk to make assumptions and get it wrong. That’s a problem.

If you hook up a 120 volt heater to a 240 volt circuit, it will fail. It will give off 4 times the amount of heat for which it was designed. For example, a 1,000 watt heater will output 4,000 watts. With that much extra heat coming from your heater you can imagine the safety concern that can cause for your family.

Alternatively, if you hook up a 240 volt heater to a 120 volt circuit, most times the heater will not work. If it does manage to run, the amount of heat it delivers will be far below what you need to heat your room.