I bought a 10,000 btu air conditioner I ran it for 4 hours yesterday
and shut the power to my apartment so I reset the circut breaker and it
did the same thing a half hour later. Is is supposed to shut the power
off to my apartment?
So you tripped the main but not the breaker to the branch circuit. Lets say
you have 100A service (an apartment might be lower, anyway it is marked on
the switch) and all the branches are 20A. Usually there are maybe ten 20A
curcuits. Obviously running them all at 12A would require 120A which would
not trip any branch curcuit breakers but certainly will trip the main.
This means your new A/C is "the straw that broke the camel's back" so to
speak. Your total load in the apartement exceeds the breaker panels
capacity. You either need to upgrade the electrical service (good luck
convincing the landloard) or turn off a substantial load or two when using
Since it took 30 minutes to 4 hours to trip, I suspect it is boarderline
(requiring you to turn off only a few things) or it is associated with
another load like an electric water heater, toaster oven, refridgerator,
stove or some combination of the items you weren't aware you were adding
My bet is on an electric water heater as they use lots of current and cycle
on and off without warning or notice. You may want to turn off the breaker
to that (WH) while you run the A/C. A bit inconvenient but less so than
resetting all the clocks and missing the best part of the game on TV while
you reset the main breaker.
Did your apartment have AC when you first looked at it? If it didn't
have it before you rented, I doubt you can force the ll to upgrade the
electricity to more conveniently run AC now.
In a few small parts of the country, there may be a special statute pr
buidling code item for buildings no older than yours that require them
all to have AC, although I don't recall hearing of such a thing. Or
if all the other apartments have it, maybe you could somehow leverage
that. OTOH, if they all did, it doesn't seem likely that your
apartment would be wired less well than theirs. Maybe your neighbors
will discuss this with you, and show you their fuse or breaker boxes.
You can see if they have more amps than you do, especially if
apartments no bigger than yours have more amps than you do.
But I think you'll need something more than just wanting it, and
you'll have to do preparation too.
No matter how you used to live, I don't think AC is required for
Now you are saving lots of money for a car and the roaches don't care
about the temperature anyway.
Next time you could try a 5,000 BTU model and it might work out OK.
Actually, you want a unit that runs all the time because you achieve
better dehumidification than an over sized unit that runs part time.
Sad posters here forgot that main breaker MIGHT be bad! They are
designed to become more sensitive and trip earlier as they age. Safety
A smaller AC like a 8500 BTU may well solve the problem.
Sadly fans dont dehumidify the main cause of discomfort when hot
Breakers do go bad though. I have run into several that would not trip
at all so I guess they broke the rule. They do generally get more
sensitive. I would bet the OP's was just overloaded. A 10,000 BTU unit
is a huge drag on a light circuit!
It sounds like you're running the air conditioner on an overloaded
circuit. When the breaker tripped, did everything (lights, dishwasher,
etc.) go out, or just the standard outlets? It's possible that all of
the outlets in your apartment are on a single 15-amp circuit, but code
would require that the bathrooms, kitchen, etc. be on separate
circuits. In any case, the problem here is clear: the circuit you're
running the air conditioner on cannot handle the additional load. You
will probably need to run a dedicated 15-amp circuit to the breaker
Most modern window air conditioners will plug into a standard 15-amp
wall receptacle, but that does not mean that you can use them on any
circuit in the house. Your air conditioner, by itself, will use a large
portion of the 15-amp service, so if you have other devices on the same
circuit, it is easy for it to go over 15 amps and trip the breaker.
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