Air handler 240v 2.5 ton

[rydan]

A/C guy just installed a new air handler and is needing a 220 line run to it .. He said the unit is 2.5 tons but the handler needs a #6 wire run to the unit ????? Its about 18ft from the panel in the attic... I was told to just run a #10 wire and a 2 pole 30 for it ... Who is right ????

 

[augie47]

The air handler with NO heat would likely be less than a 10 amp load.
The answer to your question relies on the size of the heat strips installed.
A air handler with a 10kw heat strip can often be fed by a #6 but depending on the exact numbers may require a #4 in NM cable.
You need more input. The air handler should have a nameplate giving the minimum circuit amps.

 

[rydan]

@augie47 The heat strip is 8 kw

 

[augie47]

Likely somewhere in the neighborhood of a 45 amp circuit requirement so your #6 NM should be fine.

 

[infinity]

8kw @ 240 volts is 33 amps. What does the nameplate of the unit say?

 

[augie47]

8kw @ 240 volts is 33 amps. What does the nameplate of the unit say?

( Explaination to OP, I used the 33 amps adjusted by 1.25 per 424.3(B) + a guessimated motor load as infinity notes, go by your nameplate numbers))

 

[infinity]

( Explaination to OP, I used the 33 amps adjusted by 1.25 per 424.3(B) + a guesstimated motor load as infinity notes, go by your nameplate numbers))

I figured that was how you got the 45 amps. Sounds like a good guesstimate.