Lots of interesting answers.
Assuming they are full size breakers, your contractor will pull them out and
replace them with what he needs. No problem.
Even if they are half size, he can still probably finagle something without
too much trouble.

But the person who said it depended on the size of your service was right.
If you have a 60a service you won't have the capacity. Maybe not even with
100a unless you make sure you don't use any heavy electrical devices at the
same time.

"Andrew Taylor" wrote in message
. com...
The heat has motivated me to have central air installed at my home. I am
trying to avoid getting ripped off on the electrical part of the job.

My understanding is that central air conditioning units generally pull
about 30 amps, depending on the size. At any rate, when I look at my
electrical service box, there are two 20 amp breakers that are unused. Is
it easy to somehow combine these two to support the needs of the central
air? Should the contractor that installs the AC be able to handle this as
a standard part of the job, or am I looking at additional expenses?

Thanks.