How to upgrage 110v to 220v for new air conditioner?

Old 06-10-02, 10:11 AM
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How to upgrage 110v to 220v for new air conditioner?

Trying to get a handle on whether I could tackle this myself, or would be better leaving it to a pro? Purchased a new +20,000 BTU A/C unit for large loft space. Existing A/C-specific outlet is wired for 110 w/ standard 3-prong. New unit runs on 220 and has plug w/ 1 vertical and 1 horizontal prong plus ground. Is this something a relative novice (installed a cieling fan but that's about it) can tackle, and if so, what's the best way to go about it?
Thanks aplenty,
Old 06-10-02, 10:23 AM
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Such a task is not technically taxing, and the physical ease with which it can be done is solely based on how accessible your breaker panel is and it's relationship in the home to where you need the circuit run. Even assuming that the mechanics of running the cable from the box to the A/C unit is not a problem, unless you know your way around inside a breaker panel (and feel comfortable there), you would be well advised to get professional assistance.
Old 06-10-02, 11:48 AM
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YOu will need to look at your name plate on the a/c unit. Look for "minimum branch circuit amp rating". While I understand you are using a 220 volt a/c unit you have yet to tell us what the amp rating of that a/c unit is. If you have a dedicated branch circuit direct from that panel to that old a/c unit and if that branch circuit has an ampacity equal to the amp rating or your a/c unit then you may be able to reuse the dedicated branch circuit you have for the old a/c unit just be changing it from 120 volt to 220 volt.

If your old a/c unit was plugged into a general use multioutlet branch circuit then you will have to run a new branch circuit from the panel to that new a/c unit.

We need to know if you have a single receptacle dedicated branch circuit at that a/c unit directly from the panel. We also need to know the wire size of that dedicated branch circuit and the amp rating of your new a/c unit. Then we may be able to guide you better to succeed in your project.

HOpe this helps

Old 06-10-02, 07:23 PM
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same question

I'm considering doing the same project, and is it just a matter of switching off the main circuit, adding the new 220 breaker, wiring it to the outlet (since it will be a new outlet), grounding it, and that's it? I'm sure it's more detailed, but is this the general steps taken?
here are the specs on the one i'm looking at

20,300 BTU 220 Volt 15 Amp Dedicated Circuit (Tandem Plug) * 9.4 Amps

Old 06-11-02, 05:22 PM
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Second posted question;

IF you have a 15 amp 14/2wGrnd or 20 amp 12/2wGrnd 120 volt dedicated circuit with that cable serving that existing 120 volt a/c unit on one receptacle with no other loads or receptacles on that circuit but that a/c unit's receptacle then yes you can buy a 220 volt double pole breaker matching the amps on the breaker that does not exceed the ampacity of that branch circuit. Then in the panel where the breakers are move the white wire off the neutral bar leaving the bare wire on the panel's grounding bar. Then you must change the one dedicated receptacle to a 220 volt receptacle that matches your plug on that new 220 volt a/c unit connecting the black and white wires to the brass screws of the receptacle and the bare wire to the green screw of that receptacle and you should be ready to run your new 220 volt a/c unit on your converted single dedicated receptacle circuit. Remember you can only do this conversion if nothing but that one receptacle and nothing else is on that dedicated branch circuit.

Hope this helps


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