Absorption heat pumps use an ammonia-water absorption cycle, instead of a vapor-compression cycle, to transfer heat. Ammonia is the refrigerant, and drinking water may be the absorber. The ammonia condenses at among the list of procedure’s coils to release heat and evaporates at the opposite coil to soak up heat. https://purethermal.co.uk/media-news/can-gas-absorption-heat-pumps-provide-an-alternative-heat-pump-option-in-2025/