Absorption heat pumps use an ammonia-h2o absorption cycle, rather than a vapor-compression cycle, to transfer heat. Ammonia is definitely the refrigerant, and drinking water will be the absorber. The ammonia condenses at on the list of technique’s coils to launch heat and evaporates at the other coil to absorb heat. https://purethermal.co.uk/media-news/can-gas-absorption-heat-pumps-provide-an-alternative-heat-pump-option-in-2025/