Hello
May I please ask for your help? I live in an apartment building. Last night, I turned my air conditioner on, then I turned it off, then I turned it off again (all within a couple of seconds). Now half of my apartment doesn't have power - outlets are dead, light switches don't work. How bad is the damage - will my whole apartment have to have new wiring installed? Or do I simply have to ask the super in my building to fix the circuit breakers?
Thank you!!
Bill
Probably circuit breaker....
Just move out now while you can and leave no forwarding address. Forget the security deposit, they will keep the for sure as it will cost thousands of dollars to repair.
Seriously, all you did was trip the breaker. When you shut off the AC, give it a few minutes to equalize the internal pressure before you start it up again. It put a big load on the compressor motor and just tripped the breaker taking out everything on that circuit.
As Bishoop said, probably just the circuit breaker.
The way I understand it, an ac has a very high power draw when it first turns on. If it gets switched on/off/on rapidly, sometimes the breaker could heat up & pop because of so much current draw in a very short time.
That's probably a simplified answer -- I'm NOT an electrician. I was married to one for almost 20 years, though and did a lot of "gophering" on many projects.
Newer ac units have a delay to prevent this, or so I thought....my central air has a delay for sure. If I turn it off and then right back on again, the delay prevents it starting for two minutes, to allow the breaker to cool down.
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Actually the delay is not to "protect" the breaker but to protect the motor on the compressor. If you switch it on and off and on again quickly, or the electric supplier has an outage and there is a flutter or rapid on/off/on in the power, it prevents the compressor from starting until the power has stabilized for a couple or more minutes.
The compressor also has a thermal cutout and that usually clicks off before tripping the breaker if the a/c is on it's own line. But if half the building is on a single circuit, the added current would trip the breaker first. When I lived in an apartment many years ago, I could always silence the noisy neighbor's stereo by rapid cycling my a/c.
Bob
Flip the circuit breakers or have the super do it, and don't do that it gain. The air conditioner builds up pressure and when you flipped it off and the flipped back on it tried to start before the pressure leaked down. So you essentially get a locked rotor start, which means the motor drew a lot of amps. Good way to ruin the compressor motor. Say thanks for having a breaker kick out immediately.
Jeepers. All that happens is when you start the ac the first time, the compressor runs and builds up a good pressure inside. When the ac turns off, that pressure slowly drops. The motor can start the first time because it's got a low pressure to work against, and starts normally. IF it's turned off, then on too quickly, before the internal compressor pressures can equalize, or at least drop considerably, it's too much work for the motor and the motor simply cannot turn the compressor because of the high pressure still there.
The older air conditioners have temp relays in them that limit how long a motor can try to start the compressor. When it gets hot enough, it opens and stops the motor from working. When it cools, the motor starts again, and so on until the motor is able to start. You can actually hear it clicking inside most air conditioners when it turns on and off. They are designed, by UL/CSA ETL etc requirements to work that way. It's very seldom the motor or anything else is damaged unless you maybe "wear out" a circuit breaker. Typically, if the ac is on a ckt breaker of the recommended size it will NOT pop the breaker open; the motor will just cycle, trying to start the compressor until it finally succeeds. That's why they always recommend in the install instructs that the unit be on its own electrical ckt - so it won't pop the breaker. And the breaker is supposed to have a time-delay spec also. It's in almost all of the manuals that come with the air conditioners. If the rapid on/off doesn't happen, they can usually also be run on a smaller capacity breaker, or with other things on that ckt, but then there is a lot better chanc e of popping the breaker. So, what the OP described is perfectly expected operation and NOT a sign that some super dangerous event is about to happen. It simply indicates, as the OP said, that there is not enough current available due to an undersized breaker or other loads, so the breaker/fuse opens. The newer units may well have time delays built into them that control that, and I know a few I've read about also depressurize the compressor quickly if it stops running. The latter seems to be more prevalent in this area. I've never noticed one with a two minute or whatever delay between starts but i don't look for them either. Starting and running currents are on every nameplate I've ever looked at on any air conditioner. So it's not really a big mystery for those who bother to look.
HTH, Pop
"Bill Bauer" wrote in message news: snipped-for-privacy@f14g2000cwb.googlegroups.com... : Hello : : May I please ask for your help? I live in an apartment building. Last : night, I turned my air conditioner on, then I turned it off, then I : turned it off again (all within a couple of seconds). : Now half of my apartment doesn't have power - outlets are dead, light : switches don't work. : How bad is the damage - will my whole apartment have to have new wiring : installed? Or do I simply have to ask the super in my building to fix : the circuit breakers? : : Thank you!! : : : Bill :
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