can I raise the amperage on one circuit breaker as long as I dont exceed the max amperage on the main breaker?
Answers:
Your circuit is overloaded.
The average microwave oven draws approximately 8 - 12 amps. The average window a/c units draws the same. You also need to plan for an inrush surge of current when each a/c unit is started. This inrush is typically 3 times the nameplate current rating for a couple of seconds until the motor gets up to speed.
Breakers are sized according to the wire size and load served. The smallest size wire allowed on a 15 amp circuit is 14 AWG. The smallest sized wire allowed on a 20 amp circuit is 12 AWG. If your wire is 14 AWG you may not increase the breaker size. You may find the wire size marked on the sheathing of the wire.
I would recommend installing 3 new circuits. I would put the microwave on a dedicated 20 amp circuit using 12 AWG wire and the same for each window a/c unit. If you do not feel comfortable doing this, I recommend hiring an electrician.
Other answers:
you would need to have an electrician look at your wiring to see if it is up to the increase in amps. You don't want to burn the house down
you would need to have an electrician look at your wiring to see if it is up to the increase in amps. You don't want to burn the house down
Why don't you add another breaker 15 amp, parallel to the existing one and connect the second a/c to that. You got to check with electrician for that work, because the input wiring to the existing one also needs to be checked whether it can take the extra load.
Try to find a different outlet on another circuit. Do not upgrade a breaker this way.
Likely, with a 15amp circuit, the wiring between those outlets and the panel is 14 gauge. It was intended for a few lamps and an occasional vacuum cleaner.
If you upgrade that breaker to a 20 amp, you should also upgrade the wiring to 12 gauge. Otherwise, your 14 gauge wiring could become the weaker link. You want the breaker to be the weak link so that it trips.
If you make the wire "trip" instead, it heats up... copper discolors and degrades, can melt the insulation around it, cause connections to loosen. Next thing a short happens, then sparks. And quite potentially: a fire.
Upgrading the wire is often difficult and much more effort than upgrading the wire. But it must be done.
If, by chance, you already have 12 guage wire between ALL of the points on that circuit, then I'd go for it. Turn the breaker off and determine ALL of the outlets and lights impacted. Open reach of the impacted recepticles to determine the connection sequence and wire gauge used.
While you're doing this, its a good time to re-connect any back-stabbed outlets. Often a shortcut used in 15amp circuits, is to strip a little insulation off the end of the wire and thrust it into the appropriate hold in the back of the recepticle. When you connect the 12 gauge wire, curl the stripped end and connect it to the recepticle using the side-mount srews. A much better connection.