'Nother question Window AC Units.

[donsgal]

Ok, so we decided to get one BIG window air conditioner for the living room/kitchen combo (10,000 BTU, rated for 450 sq ft, which is about right). We already have a 5,000 BTU ac in the big bed room which cools it down considerably. We only had the big unit on for about an hour in this blasted 90+ degrees, but we could tell a difference, and if we turn it on in the morning I am thinking it will be fine.

Now, here is the problem. BOTH of the ac units say "use on a dedicated circuit only" meaning, nothing else can be plugged into that circuit. So wouldn't you know that BOTH of the ac units are on the same circuit!!!! Now we will only be able to run one at a time. So "some" part of the house is always going to be too warm.

So what I am wondering is. Those of you who have window air conditioners. Do you really pay attention to that and not plug anything else in on that circuit? I told my husband I bet NOBODY pays any attention to this warning and I can't imagine that it would really hurt anything. Of course, he came unglued. It is a 15 amp circuit and the big ac unit pulls 9 amps. (I don't know what the small one pulls). He says there is a chance of fire because heat builds up due to "resistence" or something like that if too much amperage is going through the wires.

Tell me what you think.

donsgal

[WolfWalksSoftly]

Either move one of the outlets to another breaker or get a heavy extension cord and plug into an outlet on another breaker.

I would think a breaker would shut off first before any problems,especially if there is one built into the A/C cord.

[Beltane]

I would just move one of the outlets to a different breaker, or add one. Check and see if your panel has any unused spots.

[big rockpile]

Originally Posted by WolfWalksSoftly

Either move one of the outlets to another breaker or get a heavy extension cord and plug into an outlet on another breaker.

I would think a breaker would shut off first before any problems,especially if there is one built into the A/C cord.

I'm thinking the same as far as the Breaker kicking off.I'm sure we have other things on the same Breakers as our A/C Units.

I sure wouldn't use a extension cord.

big rockpile

[artificer]

The circuit breaker will protect the wires in the wall from getting too hot. That's what they're designed for. If someone put a larger breaker in, because the old one kept tripping, or the breaker is defective, then you have problems.

The worst that can happen with a properly functioning breaker is that it will keep tripping. This is assuming it's working properly, which is a somewhat safe bet.

It is a good idea to not load a circuit to more than 85% of rated capacity. 13 amps on a 15 amp circuit.

Another reason you don't want additional loads on the circuit with the AC unit is because of the starting load. Most motor driven devices draw 4-5 times their running amperage when they start. This happens each time the compressor cycles on. If you circuit is really loaded up, you'll probably end up tripping the breaker. Small additional loads (clocks, radio, fan) would be fine.

The best bet would to go with the heavy extension cord for the smaller AC unit that wolfwalkssoftly mentioned. (heavy being 12 gage wire, not the) As long as its short, you should be fine.

Michael

[nehimama]

IF I were to use an ext cord, I'd be darned sure it was one labeled for large appliances. Might be safer and cheaper in the long run to somehow get the 2nd AC unit on a dedicated breaker. Better that than to risk a fire!

NeHi

[Esteban29304]

They really should be on separate circuits. They may both run OK at the same time,,,, but if both of their thermostats tried to kick in at the same time, the " draw " would be too much. You can buy a extension cord for this,[ NOT a thin cheap one ] ASK in hardware store. If you are lucky, you may be able to plug one in an opposite wall, & be on another circuit. DON'T run cord under carpet or rugs !!!!

[amwitched]

When we purchased the large window unit for our home, it wouldn't even run on the plug in the wall. It constantly popped the breaker. We had to have an electrician install a new breaker just for that unit. We also had him run that breaker outside so DH could use it for his power tools when he needs them. Our smaller window unit does just fine plugged into the regular outlet.

[michiganfarmer]

if it doesnt trip the breaker, I run it

[Jeslik]

I can't run my whole - house fan (for the back half of the house), Living Room AC (for the front half of the house), the TV, and the lights without blowing a fuse. I can drop any one of those devices, and its fine. But they are all on the same line in this 80 year old house, and given how old the wiring is in this beast (rental) I really don't want to run it at max load. So I usually don't turn the AC on - it just makes the bedroom AC more enjoyable at night, and it saves a fortune. If it were my own property, I'd do all sorts of improvements...

PS make sure that your AC drips well away from the house; the AC in the bedroom dripped down the brick and the extra moisture encouraged mold to develop on the interior wall. Find some way to get the AC condensation away from the house. I stuck a piece of sheet tin under the AC so it drips now a good foot away from the structure; problem solved. it's ugly, but it does the job.

[tamsam]

How old is the house and do you know what size wires are in it. Some of the older houses and most mobile homes have either 16 or 18 gauge wire in them. If it is 18 gauge I wouldn't even run an ac unit. Best way to be sure is have an electrican check it out. Good luck and let us know how it works. Sam

[cfabe]

If the house is older than say 30 years or if it's of questionable build quality (mobile home, DIY work, etc) I would not run them both on one circuit. In theory, if the house is wired properly and has working breakers of the proper value for the circuit, the breaker will protect the house wiring from overload, but in reality there are a number of ways this can start a fire without tripping the breaker. If you own the house, having someone install a dedicated circuit shouldn't be terribly expensive, if you're renting, use a heavy extension cord (14ga or 12ga would be better) to plug it in to a different circuit.