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Electrical Wiring in the Home/Wiring for floor heating Thermostat


QUESTION: What do I do with the White wire for a 120 incoming wire?  Just hook up the L1 and then cap the white wire?

ANSWER: If it is a line voltage thermostat for a 120 volt unit, the white wires bypass the thermostat and get hooked to each other.

---------- FOLLOW-UP ----------

QUESTION: Thanks.  I'm hooking up a schlueter programmable ditra heat thermostat.  There are two black, and two yellow wires on the thermostat.  The 2 black say L1 and L2, and the yellows are to hook up to the ditra heat cable on the floor.  For the 120 thermostat, I assume I hook up my black hot wire from the fuse box to L1, but then what happens to the white wire from the fuse box?  Also, One of my thermostats will have 220.  I assume the hot black goes to L1 and the hot red goes to L2, but again what happen to the white wire?  Any help you can give on this would be great.  I cannot find anyone or anything else that explains this to me.

For 110 volt thermostats, the white wires bypass the thermostat, so they would hook to each other.  For 220 volt thermostats, you need only the red and black.  The white need not be connected to either end. Baseboard heat is unlike dryers and stoves, because there are no 110 volt components, so there is no need for a neutral.  Only two hot wires.
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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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