Tapping into tankless water heater receptacle

Old 04-02-15, 09:35 PM
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Tapping into tankless water heater receptacle

I want to power some low voltage lighting by tapping into a 20 amp circuit that powers a tankless water heater and garage with one overhead light and garage door opener.

I want to grab power at the tankless heater. The heater is mounted on an outside wall plugged into a single outlet housed in a one gang receptacle.

The power required to run the tankless is 120VAC/60 HZ

The water heater draws 6.2W/0.05 A while operating.

I want to convert the single outlet to a double outlet and mount the transformer next to the receptacle. The low voltage wire would run about 10 feet to a nearby pathway. Probably 6-8 low voltage lights would be in the pathway.
Old 04-02-15, 10:46 PM
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The voltage required is 120vac. The power or amperage draw is much higher than 6.2w and .05a.
It should be more like 1000w or 12A.

If the circuit is sized for a particular appliance you usually can't safely just "tap" into it.

This also sounds like a sink mounted instantaneous water heater..... not really called a tankless.

Double check the heater specs for us.
Old 04-03-15, 07:51 PM
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While nothing prevents you from using twofers (Y connectors) (or power strips) to plug two things into one wall receptacle, you should add up the wattages or amperes of the things you expect to use so you do not overload the circuit. Since you already have some lights and a garage door opener on the circuit in addition to the water heater, you really should think about stringing a new circuit for additional stuff.

As a general rule, if something would use more than half the amperage of an otherwise ordinary branch circuit with multiple receptacles, it should have its own (dedicated) circuit.
Old 04-06-15, 04:37 AM
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PJmax: If it's a gas tankless, the current draw will be quite small (only enough to power the control circuitry). Mine draws far less than 1 amp.
Old 04-06-15, 06:55 AM
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Most manufacturers state to keep the heaters on a dedicated circuit. If not powering things from the same circuit may mess with the internal elctronics of the heater.
Old 04-08-15, 09:58 PM
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I will stick with solar for now until I can come up with a more efficient option.


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