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 will be the absorber. The ammonia condenses at one of the process’s coils to release heat and evaporates at another coil to soak up heat. Suitable standards https://purethermal.co.uk/media-news/can-gas-absorption-heat-pumps-provide-an-alternative-heat-pump-option-in-2025/