This is the component of common residential HVAC systems found outdoors, and represents what most people picture when they think of an “air conditioner”.
The air conditioning or heat pump condensing unit is the HVAC part of the system located outside and houses the compressor, condenser coils, condenser motor and fan. The primary difference between an air conditioning and heat pump condensing unit is that the latter includes a reversing valve that allows for the reversal of heat transference—heating during winter; cooling during summer. Condensing units are easily recognizable as self-contained, metal boxes located adjacent to the buildings they serve. These boxes are typically vented in some fashion and include a screen-covered fan and are attached to the building via electric wiring and condenser lines.