Digital thermostat mounted on a concrete wall

Generic photo: Alexander Mass · Pexels License

Install a line-voltage thermostat (electric baseboard or wall heater)

Baseboard and wall heaters are controlled by line-voltage thermostats that switch the full heater current, usually at 240 V. They are not the same as low-voltage HVAC thermostats. Use a double-pole model rated for the heater load on 240 V so both legs open in the OFF position, and wire line to line and load to load exactly as the instructions show. This is mains wiring: kill and verify power, and use a qualified electrician where required.

Cross-checked ~45 min moderateBrands: All

Before you start

Line-voltage thermostats carry 120/240 V: turn off the breaker, lock or tag it, and verify dead on every conductor with a meter before touching wires.
Never install a low-voltage (24 V) thermostat on a baseboard circuit.
Use a thermostat rated for the heater's voltage and total watts/amps.
Any new circuit, breaker change or damaged or aluminum wiring: qualified electrician where required by local code.

Diagnostic steps

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