[header] How to wire a 220 outlet [title] Check with the national and local electrical codes. [step] Make sure you understand all the requirements for wiring a 220-volt outlet. [title] Choose the correct wire size and type for the appliance. 
[step] A label should give the amperage rating of the appliance, and this will determine the wire size. An example would be a 20 amp air conditioner requiring a 12 gauge wire, typically a 3 wire plus ground romex cable.