HVAC power wiring

Old 05-23-15, 10:28 PM
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HVAC power wiring

Hello,first time posting on this site.Thanks in advance for all replies.

I'll start by explaining what i have done.I've replaced my heating unit with a new one from one side of the attick to the other and now i need to extend my power feed about 20 feet.The old unit was feed by a 2 gauge aluminum wire with a 90 amp breaker,but the new unit requires 2 feeds of 30 and 60 amps.What is the best way to extend the power feed?
Old 05-23-15, 11:08 PM
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Welcome to the best DIY forum on the Internet.

There are several possible ways to extend the power, perhaps one of the best would be to use a power block connection mounted in a steel cabinet. This is one example. Others will have a more in-depth answer.


I would use copper conductors with type THHN insulation, #6 for the 60 ampere and #10 for the thirty ampere. You need to run these conductors through conduit. Understand that you may NOT connect the copper and aluminum conductors directly to each other.

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