This part of ISO 13256 covers heating and cooling systems which are generally referred to as "water-source heat pumps." These systems generally include an indoor coil with air-moving means, a compressor, and a refrigerant-to-water or refrigerant-to-brine heat exchanger. A system may provide both heating and cooling, cooling-only, or heating-only functions. This part of ISO 13256 establishes performance testing and rating criteria for factory-made residential, commercial and industrial, electrically driven, mechanical-compression type, water-to-water and brine-to-water heat pumps. The requirements for testing and rating contained in this part of ISO 13256 are based on the use of matched assemblies. Equipment designed for rating at one application under this part of ISO 13256 may not be suitable for rating at all applications covered in this part of ISO 13256. This part of ISO 13256 does not apply to the testing and rating of individual assemblies for separate use or to units having two or more indoor sections connected to a single outdoor section. It does not apply to heat pumps covered in ISO 5151, ISO 13253, or ISO 13256-1.

Keywords: Water Source Heat Pumps, Heat Pump Equipment, Heat Pump, Heat Pump Efficiency, Heat Pump Rating, Heat Pump Capacity, Cooling Capacity, Heating Capacity