Comment by carrotsalad

The article describes this as a "monobloc" air-to-water heat pump. Monobloc means that the compressor, fan, and all the refrigerant are entirely sealed within the outdoor unit, and it just sends a loop of water (or water w/ glycol in it) into the house, where it can warm or cool an insulated buffer tank that effectively stores the hot or cold water for use in heating, cooling, and domestic hot water.