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I have a 240v outlet I can use as my source but it doesn’t have a common white. The fireplace needs a 3 wire connection (15 Amp 240V). Can I bring a single white common wire from a nearby 120v outlet? I don’t want to run a whole new line from the panel. Thanks.

isherwood
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Richard
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    This is a common problem with ovens and clothes dryers - they need a neutral for some relatively small 120V parts of the appliance. It is trivial (at the design phase) to make the entire appliance work with 240V. Notice that your typical computer power supply will run from 100V - 250V with no switches or other changes needed. But manufacturers are stuck in the 120V/240V split mode that goes back to many, many years and have no real incentive to change. – manassehkatz-Moving 2 Codidact Dec 05 '22 at 17:57
  • @manassehkatz-Moving2Codidact Agree totally. A very inexpensive transformer (240 down to 120) would eliminate the need for a 4 wire connection, although 4 wire is required by code now and has been for many years. – George Anderson Dec 05 '22 at 18:32
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    @GeorgeAnderson 4-wire is the standard receptacle to be provided for a clothes dryer. But I never heard of a *required* electric fireplace connection, so no reason that should need to be 4-wire. – manassehkatz-Moving 2 Codidact Dec 05 '22 at 18:36
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    @manassehkatz-Moving2Codidact Again, no arguments from me. I think like you do that it's stupid that appliance manufacturers don't either run the control circuitry on 240 or just use a super inexpensive, simple transformer to provide 120v....I mean, what do they do for European appliances where everything is 240 v? – George Anderson Dec 05 '22 at 18:52

2 Answers2

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"Borrowed neutrals" are potentially dangerous to anyone working on the installation.

When you turn off the breaker to a circuit, you would expect it to be safe to work on. But if another circuit has borrowed the neutral, it can back-feed power from a completely different breaker. The end result is that a neutral suddenly becomes live. And it may only become live when someone turns on a completely unrelated appliance.

Simon B
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No you can't. The common, white wire, has to be run with the power legs. Ground wires can be run separately but not common/neutrals. If you have a conduit installation, you can pull in a neutral, if cable, you'll need to pull a new line.

JACK
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