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parttime
Aug 31, 2010, 04:34 PM
Hi, I have a wall mounted air conditioner that's 21,300 BTU, 240 volts and 13 amps. (as read on the plate). Is this OK to be on a 2 pole 20 amp breaker with 12 gauge wire. It's a dedicated circuit that runs about 25 feet. Thanks for any help

ma0641
Aug 31, 2010, 06:58 PM
Should be OK. Even if you downrate some for possibly running quite a bit and take some voltage drop, 20 works out.

tkrussell
Sep 1, 2010, 02:38 AM
The nameplate should also state MCA, Minimum Circuit Amps, to size the wire, and max fuse or breaker size.

parttime
Sep 1, 2010, 04:08 AM
Thanks for the responses, tk, I thought that info should be on the plate, I'll take a closer look this morning.

parttime
Sep 1, 2010, 06:56 AM
I checked the plate again and that info is not on it. Just has what I posted first time.

tkrussell
Sep 1, 2010, 07:10 AM
Is this a new unit? Make and model number? May be in the datasheet or manufacturers instrucitons, should be on the nameplate thou.

Maybe plug in units are different.

You can go by the male plug also, but somewhere in the manufacturers documentaion should be what size circuit is needed.

By the way, I agree with Ma0614, I am just mentioning how a circuit should be rated for an AC unit.

parttime
Sep 1, 2010, 08:38 AM
Tk, this is an old unit, no paper work available at all, this is in the upgrade you assisted in a week or so ago. It was wired with 10/3 on the outside wall of the house and the old cable will not reach the new 200 amp service, just trying to make sure I'm right when I fish through the walls. Thanks again for the help, inspector was impressed.

tkrussell
Sep 1, 2010, 08:40 AM
OK I meant to mention if it was an older unit, nameplates were done differently then.

Impressing an inspector is always a good thing. Well done.

parttime
Sep 1, 2010, 10:23 AM
Had to spread the rep, Well done on your part. Thanks