Converting hard wired to a plug and receptacle.

Old 01-11-15, 02:43 PM
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Converting hard wired to a plug and receptacle.


I live in Quebec, Canada. I have an hydronic heating system: an electric boiler heats the water and a pump is moving it through the pipes and radiators.

During winter, in the case of a power outage, I would be heating with a wood stove, but i would like to be able to plug my pump on my Honda 6500SX power generator, in order to prevent the water from freezing in the corners of the house. My radiators would work in reverse: providing heat to the water from the ambient heat coming from the stove.

I recently changed the pump (see this for reference). The old pump (Bell&Gossett Series 100) was directly wired to the inside of the boiler with a AWG-12 wire. The 20 kW boiler is connected to a 240V, 125A circuit breaker. In the manual of the new pump (Bell&Gossett NRF-33), it says that the pump uses 125W, and requires at least an AWG-14 wire.

Instead of a direct wire between the boiler and the pump, i need to have an electrical outlet connected to the boiler, and have the pump connect into it. That way, when the power is out, I could plug the pump into an extension cord. You can see the result below:

Like I said, the old wire was a AWG-12, connecting the boiler directly to the pump. But the new pump only requires an AWG-14. Is it correct if the new wires are both AWG-14 (white is solid and black is stranded)? I guess that the black wire can be considered the "pump" wire, so I guess AWG-14 is ok for that one, but should I put back an AWG-12 wire for the white wire (between the boiler and the outlet)?

What does the code say about situations like that, where you may have for example, a 20 AMP breaker that requires AWG-12, but an application that requires less? Does the outlet end the AWG-12 requirement? Does being inside/outside a wall change the requirements?

I'll probably change back the white wire to an AWG-12, but I'm wondering if I need to continue with AWG-12 for the black wire too.
Old 01-11-15, 05:55 PM
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Search for a single circuit transfer panel. It is made to do what you want and still meet the safety requirements of a interlock or transfer switch.
Old 01-12-15, 07:51 AM
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Yep, Reliance makes a single circuit transfer switch that is commonly used on gas furnaces.

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