How to Wire a 240-Volt Electric Baseboard Heater
- 1). Turn the main power/circuit breaker off in the service panel. Using the screwdriver, remove the screws holding the cover panel over the service panel box. Set it aside.
- 2). Drill a hole into the wall behind the left side of the heater, using the drill and 1/2-inch drill bit. If the baseboard heater is already in place, lift it off the the mounting clips and set it to the side.
- 3). Drill a hole in the top plate of the wall directly over the location of the baseboard heater. Feed the Romex cable, from the attic, down the wall to the drilled hole. Have an assistant pull about 6 inches of the wire out the hole, as you feed it down the wall.
- 4). Feed the remaining end of the Romex cable down an existing hole along with the existing cables that are running into the service panel. Have the assistant pull about 2 to 3 feet of the cable out of the front of the service panel as you feed it down through the hole.
- 5). Prepare the end of the cable in the service panel, by stripping off about 14 inches of the outer insulation off the cable. Separate the three wires inside and strip 1 inch of insulation off each of the two insulated wires.
- 6). Locate an open 220-volt circuit breaker in the service panel. Insert the black wire under one of the screws on the breaker and the white wire under the remaining screws and tighten them down. Tear off a 2-inch piece of the electrical tape and wrap it around the white wire as a reminder that this wire is hot. Attach the bare, or ground, wire to the grounding strip at the bottom of the service panel.
- 7). Replace the cover over the service panel, and tighten each screw down with the screwdriver, securing it in place.
- 8). Strip about 6 inches of the outer insulation off the end of the cable at the heater. Strip 1 inch of insulation off each insulated wire.
- 9). Attach the wiring to the heater by first unscrewing the service panel on the rear of the heater. Slide the bare, or ground wire under the green screw on the heater frame and tighten it down. Locate the two black wires inside the service panel. Connect each of these two black wires, one to the white wire feeding from the service panel, and the other to the black wire. Connect them by twisting the ends of the wires together, and then twisting a wire nut on the end, to secure the connection.
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Replace the service panel on the rear of the heater and tighten the screws down. Reattach the heater to the mounting clips on the wall to hold it in place. If the clips need mounting, then use the included template with the heater to mark the locations on the wall and screw the clips into place to mount the baseboard heater. - 11
Turn the power back on at the service panel. Turn the heater on and adjust the built-in thermostat to test for heat.
