What power protection do i need to install my air conditioner?

Question

I just got a portable air conditioner. It requires 115v 15a. I have it plugged into the outlet in my room. The plug says on it that i need a circuit breaker or timed fuse. My house has circuit breakers, im wondering if this is all it requires. The lights dimmed a little when the compressor turned on, but the same happens when i turn on my vacum cleaner. I just want to make sure that im not going to die in a horrible fire.

Answer 1

Your fine if it only requires 15a your wall outlet should be 20a,but the minimum it will be is 15..

don't plug anything else into that outlet.....

Answer 2

I agree with everything DSM said, but I question a bit whether it is actually using a full 15a, it may be requiring a 15a circuit, but actually using less.

Recheck the numbers on the plate; also, what's the BTU rating?  Today's units are close to 10 EER, so if it is a 10,000 BTU unit, the current draw is probably around 10a.  

No real danger of fire, if your house is properly wired, the worst that would happen is the breaker would pop if you had other stuff on that circuit, a definite inconvenience, but that's what it is supposed to do to avoid overloading the circuit.

A little light dimming is normal, since a compressor does just like your vacuum cleaner, there is a startup surge.

Oh yeah, don't plug your vacuum cleaner into that same outlet (or circuit, if you know) when the A/C is on, you probably WILL pop the breaker.

Answer 3

It is very likely that the circuit you plugged it into is rated for a total of 15 amps. That means that everything in addition to the A/C is really not supposed to be on the same circuit. Large items, like A/C are supposed to be on their own circuit.

If you are in the U.S., you are probably okay. That is because 15 amps is the minimum circuit capacity in the U.S. The fact that there are other things on there is probably not a real problem. In theory, it is wrong; in practice, it is probably okay.

If you have more symptoms that what you already wrote, I would get the situation re-evaluated. Can you have an electrician run a dedicated circuit to the A/C? Since you said it was a portable unit, I assumed not.

If it were mine, I would run that circuit. Then again, I don't have to pay for it. Second best would be to turn off the breaker to that outlet. With it off, see what else doesn't work.

My fear is that the lights will be on the list of things that does not work. It is against code, and a bad idea to have lights and outlets on the same circuit. That was common a few decades ago, so it wouldn't surprise me.

The reason that I would want to know is that it tells me more about what else is on the same circuit. There isn't much you can do about it without spending a lot of money, but I am curious.