The household air-source heat pump unit integrates both cooling and heating sources, eliminating the need for a separate refrigeration room or boiler room. The unit can be placed anywhere on the roof or ground, without occupying the building's usable space, and is extremely easy to install. It doesn't require a cooling water system, thus there's no consumption of cooling water or energy for the cooling water system. Moreover, there have been numerous reports of Legionella infections caused by cooling water pollution. From a safety and hygiene perspective, air-source heat pumps offer a significant advantage.