This is the seventh in a series of Heat Pump 101 videos from instructor and author, John Siegenthaler, P.E.. “Four Common Types of Heat Pump Configurations” was the previous lesson in the series. You can enroll in John’s Heat Pump 101 course for free to learn the very basics of heat pumps in less than an hour.

[Note: In this video John accidentally says ‘air-to-water’ right at the start. Don’t be confused. He’s talking about air-to-air systems and corrects himself quickly.]

Air-to-Air systems were the original heat pump configuration that companies like Carrier began experimenting with back in the 1950s. It’s by far the most common type of heat pump currently deployed in the US.

Any system that has an indoor and an outdoor portion connected by refrigerant tubing is called a split system. You may also hear the terminology, “central system”, and that simply means that there’s a single air handler that delivers heat to a duct system that then carries that heat throughout the building.

We don’t necessarily have multiple indoor air handlers, and it may be configured with multiple indoor air handlers with no ducting. These systems are called ductless, or sometimes you’ll hear the term mini-split.

The next video in this series describes how water-to-air heat pumps work. If you want to see that video now or jump ahead to the others, you can find them all in John Siegenthaler’s free Heat Pump 101 course.