Electrical Wiring in the Home/wiring two baseboard heaters


I have two baseboard heaters, the thermostat, and the feed.  I would like to see a diagram of how it's put them together at a junction box.  My wires are coloured black and red plus the ground.

I can't make a diagram, but I can tell you how to wire it.

Since both legs are hot, both must go through the thermostat.  The black and red wires from the source go to the line side of the thermostat.  The black and red wires going to the heaters connect to the load side of the thermostat. Depending on how the wires are laid out, either the wire goes to the first then the second heater.  Or the two wires going to the heaters connect to the thermostat at the load side.

If the wires go from heater to heater, at the first heater, the wires coming and going connect to each other plus the wires from the heater. At the second heater the red and black connect to the two heater wires.

If the wires are separate to the heaters, the red and black connect to the two heater wires at each unit.  At the thermostat, you probably can't get two wires to connect to the load side screws, so you'll have to run a short piece from the thermostat and wire nut them to the wires going to the heaters.

In either case, the bare ground wires connect to each other, to any green wires and green screws, plus to the metal heater frame and any metal junction boxes.
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Electrical Wiring in the Home

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Bob Sponaugle


Just about any home wiring question. (not appliance repair) I have done all kinds of home wiring for myself, including adding a new breaker box, etc. Please, questions from North America only. Please be specific with details.

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