Home Inspection State Practice Exam

The minimum ampacity required for the service to a house that operates a central air conditioner, electric clothes dryer, and electric range is determined by considering the power demands of these appliances. Typically, a central air conditioning unit can require significant amperage, often around 20-30 amps depending on the size and efficiency. An electric range and dryer each also have their own amperage requirements, commonly ranging from 30-50 amps when running at full capacity.

When calculating the overall service demand, it's essential to account for the fact that not all appliances will be used simultaneously at their maximum capacity. However, the code and safety standards generally estimate demands more conservatively.

A service of 100 amps at 240 volts is often the standard for moderate-sized homes allowing for the simultaneous operation of the central air conditioning system, clothes dryer, and range while still accommodating general circuit needs for lighting, outlets, and other appliances. It provides a robust capacity that allows for additional loads that may arise, ensuring that the electrical system remains safe and reliable under various usage conditions.

Choosing a lower ampacity, such as 60 or 80 amps, would typically not provide sufficient capacity for larger appliances and the additional circuit loads in a typical household. A 150-amp