what gauge extension cord should I use for a 19 ft. travel trailer with an air conditioner using 110?

8 guage for 50 amp
10 guage for 30 amp
12 guage for 25 amp
14 guage for 15 amp

I think trailer park outlets have 40 amp service? I would go with 10 gauge since its a short run.

It would not hurt to get the biggest (gauge) one you can buy. It really depends on the length, though. The longer the cord, the heavier the gauge should be. For a 100' running (I'm guessing) a 10 Amp air conditioner unit, 14 gauge should be sufficient. If there is anything else that needs power, or if the air conditioner is rated for more than 10 Amps, then you should go for the 12-gauge cord.

If you only go for a 50' cord, 14 gauge should be OK for powering everything.

I would not buy a 16-gauge cord under any circumstances.

Anything thicker than 12-gauge is a specialty cord (as the answerer above mentions) -- not a general-purpose extention cord. If your run is very short (25' or less) and you are powering 120 VAC at less than 20 Amps, then 12 gauge is sufficient (that is what is inside your house in the walls).

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