How to Find Your Heater's Wattage

Before buying, you'll want to confirm your heater's wattage falls within Mysa's supported limits (see Wattage & Amperage Limits). Here's how to find that number.

Check the rating plate

Most electric baseboard, convection, fan-forced, and radiant heaters have a metal rating plate stamped or printed with the wattage, either:

• On the heater unit itself (often on the end cap or back panel)

• Inside the heater's wiring compartment, under a removable cover

Look for a number followed by "W" (watts) — for example, "1500W" or "2000W."

If you have multiple heaters on one circuit

Add up the wattage of every heater on that circuit — not just the one nearest the thermostat. See Wattage & Amperage Limits for how combined wattage affects your limit.

If you can't find a rating plate

• Check your breaker panel — the amperage of the breaker feeding that circuit (commonly 15A or 20A) can help narrow things down, though it isn't a substitute for the heater's actual rating

• Take a photo of the heater and email install@getmysa.com — our team can often help identify the model and wattage

General sizing guidance (if you're buying a new heater)

If you're installing a brand-new heater rather than replacing a thermostat on an existing one, a common industry rule of thumb is roughly 10 watts per square foot for supplemental electric baseboard heat in an averagely-insulated room — but this varies significantly with ceiling height, insulation, climate, and window area. For accurate sizing of a new heater, consult the heater manufacturer's sizing chart or a licensed electrician rather than relying on a rule of thumb alone.

Get Support

Email install@getmysa.com with a photo of your heater's rating plate if you need help confirming compatibility.