How to Control More Than One Heater With a Single Thermostat
- 1). Turn off the breaker or remove the fuse that provides power to the thermostat. Remove the screw holding the cover on the junction box at the end of the baseboard heater that is currently controlled by the thermostat. Remove the cover plate.
- 2). Remove the screw holding the cover on the junction box at the end of the baseboard heater that is to be controlled by the thermostat. Remove the cover plate.
- 3). Run an appropriately sized two-conductor wire from the junction box of one baseboard heater to the junction box on the other baseboard heater. Secure the wire, as necessary, using wire staples and a hammer.
- 4). Strip the jacket off the two-conductor wire in the new heater to expose the black, white and bare copper conductors inside. Strip 1/2-inch of insulation off the black and white conductors. Wrap the bare copper ground wire around the green ground screw in the junction box. Turn the screw clockwise with a flat screwdriver until it is snug.
- 5). Remove the wire nut from the two black wires inside the junction box of the new heater. Slide the bare end of the black conductor and the bare end of a black heater wire into a wire nut and turn it clockwise until it is securely attached to the wires. Slide the bare end of the white conductor and the bare end of the other black heater wire into a wire nut and turn it clockwise until it is securely attached to the wires. Coil the wires into the junction box, replace the cover and tighten the cover screw until it is snug.
- 6). Remove the wire nut connecting the black heater wire and black conductor from the thermostat in the junction box of the existing heater. Slide the bare end of the black conductor connected to the new heater into a wire nut with the black heater wire and black conductor from the thermostat. Turn the wire nut clockwise until it is snug.
- 7). Remove the wire nut connecting the black heater wire and white conductor from the thermostat in the junction box of the existing heater. Slide the bare end of the white conductor connected to the new heater into a wire nut with the black heater wire and white conductor from the thermostat. Turn the wire nut clockwise until it is snug.
- 8). Turn the screw holding the bare copper ground wire inside the junction box counterclockwise until the wire comes loose. Twist the bare copper wire from the new heater together with the bare copper wire from the thermostat. Slide the end of one of the bare copper wires under the ground screw and turn it clockwise until it is snug. Coil the wires into the junction box, replace the cover and tighten the cover screw until it is snug.
- 9). Turn the breaker on or replace the fuse to restore power to the thermostat. Turn the thermostat to its highest setting and check to make sure that all connected heaters operate. Turn the thermostat off and check to make sure that all connected heaters cool down.
- 10
Turn off the breaker or remove the fuse and check all fuses, breakers and connections if the heaters fail to operate correctly.
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