How to Wire a Baseboard Heater for 220 Volts
- 1). Disable power to the circuit you will be connecting the baseboard heater to. If you do not already have a 220-volt circuit installed, continue to Step 2. If there is an available 220-volt circuit, skip to Step 3.
- 2). Install a two-pole, 30-amp breaker into your breaker box. A standard single-pole breaker carries a 110-volt signal, while the two-pole breaker will double the voltage, creating the 220-volt circuit you'll need for your baseboard heater. If you are uncomfortable with adding a circuit to your home's electrical system, consult an electrician to have the circuit installed.
- 3). Run a 12/2 three-wire NM cable with a bare ground from the circuit breaker to the location where the heater is to be installed.
- 4). Remove the cover from the junction box on either side of the heater. Strip the covering from the NM cable revealing the three wire strands within, two colored leads and a bare ground. Thread these wires through the knockout located on the junction box and secure with a wire clamp.
- 5). Connect the bare ground wire from the circuit breaker to the bare wire located in the heater's junction box with a wire nut.
- 6). Connect the two leads from the circuit breaker each to one of the black leads in the junction box with a wire nut.
- 7). Restore power to the heater's circuit and test for proper function. If the heater is not working, disable power to the circuit and double-check that all wiring is correct and secure.
Source...