220v wall heater replacement questions

Old 02-08-20, 11:39 AM
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220v wall heater replacement questions

Have a 220v wall heater that is going to be replaced with a 120v fan/light/heater combo unit in bathroom. There is another 220v wall heater in the bedroom that is on the same 30A double pole breaker. If a heater requires a dedicated circuit, is having 2 of them on one still dedicated? Am I correct that in order to do this proper, the DP30 would stay for the remaining heater? I would then need to add a 20A single pole AFCI breaker dedicated to the new fan/light/heater?
Old 02-08-20, 12:31 PM
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It may or may not be possible to put both new heaters on the same branch circuit. Each has both a minimum and a maximum branch circuit amperage rating.

A circuit rating should be specified in the instructions or on a name plate. If a "maximum amperage" rating
is not stated, then take the recommended circuit amperage or take the figure given as the minimum rating..

If one heater normally operates using more than 40% of its maximum rated circuit amperage then you cannot run two of them on the same circuit.(Heaters are considered "continuous loads" and as such, one should not be used on a circuit where it would draw more than 80% of the circuit rating.)

Common U.S. small appliances and consumer electronics and other devices should rated for at least a 20 amp 120 volt circuit permitting their use on such a circuit, which is common in the U.S. Depending on the scope of the total project and the local regulations, the old circuit may need have an equipment grounding conductor, typically another conductor (bare of green insulated) accompanying the other two.

The old circuit wiring may not be used for a 120 volt circuit in the U.S.unless one current carrying conductor is white (and the other of a different color).

Last edited by AllanJ; 02-08-20 at 12:53 PM.
Old 02-08-20, 12:34 PM
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Since the new heater combo unit is 120v and not 240v you will need to run a new circuit for it.

If a heater requires a dedicated circuit
A heater is not required to be dedicated unless it takes more than 50% of the branch circuit rating.
Old 02-08-20, 12:59 PM
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My opinion - I think that you will find that a heater as part of your bathroom fan/light is near worthless. I had one and got rid of it. Any heat it produces stays up around the ceiling except when the exhaust fan is on. Then it goes out the vent to heat your yard.
Old 02-08-20, 01:42 PM
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If a heater requires a dedicated circuit, is having 2 of them on one still dedicated?
No it is not. Dedicated is one item only.

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