electric base board heaters

Old 04-20-14, 09:44 AM
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electric base board heaters

I am installing two electric base board heaters, a main unit with the thermostat and a slave unit. The main unit is working fine and responds to the thermostat settings but the slave is on constantly. The only way to stop heat to the slave is by shutting it off at the panel.
I am replacing old heaters and the wires coming out of the wall are black red white and ground. the Slave only has two blacks and a ground screw.
I had the heat but no thermostatic control when I had a black from the unit connected to the black from the wall and the red from the wall connected to the other black. When I tried to connect the black and red from the wall (leaving the red capped), I got no heat at all.
The instructions are no help at all.
Any suggestions?
Old 04-20-14, 09:53 AM
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Welcome to the forums.

Normally with baseboard electric heat you would use one master wall thermostat or each unit would have its own thermostat.

Right now you have a 240vac supply going to both heaters. You would have to bring the wiring from the slave heater into the heater with the thermostat. That would mean that you would have a single 2 wire cable at the slave heater and two 2 wire cables at the primary heater.
Old 04-20-14, 04:27 PM
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I would not wire up the second heater as a slave to the first without verifying that the thermosrat control on the first heater can handle the total load (in amperes) of the two heaters.

If you make connections inside the heater you may need to use special high temperature connection methods. Ordinary wire nuts might not do. Often the connections inside heaters are welded or crimped.

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