Bathroom receptacle locations. Spa, hot tub, and pool circuits. Oversized circuit breakers are often present. The size or diameter of the branch circuit wire determines the amount of amperage the wire can safely carry without overheating and becoming a fire hazard. The circuit breaker size should be determined by the wire size.
Higher efficiency means less required amperage to run the unit.
It is common to find the original circuit breaker servicing a newer AC unit. This device is installed to prevent the water heater from exploding when the unit overheats. The valve should have a drain line attached to it which meets the following criteria. The drain line is directed downward and never sloped upward. The drain line is not reduced in size.