How Air-Source Heat Pumps Work and Daily Maintenance

　　Air-source heat pump water heaters, also known as “air-source heat pump water heaters,” absorb low-temperature heat from the air. This heat is transferred to a refrigerant, causing it to vaporize. The vapor is then compressed by a compressor to increase its pressure and temperature, and this high-temperature thermal energy is transferred to the water via a heat exchanger to heat it.

Air-source heat pump water heaters operate based on the “reverse Carnot cycle” principle. Specifically, the “outdoor unit” acts as a heat exchanger to absorb heat from the outdoor air, heating a low-boiling-point working fluid (refrigerant) and causing it to evaporate. The refrigerant vapor is then compressed and heated by the compressor before entering the water tank, where it releases heat to the water and condenses into a liquid. It then undergoes throttling to reduce pressure and temperature before returning to the outdoor heat exchanger to begin the next cycle. Simply put, it absorbs heat from the air to heat water, and the air from which heat has been absorbed can also be utilized in the kitchen to alleviate stuffiness.

Heating using the heat pump principle is the opposite of air conditioning cooling—the national standard for cooling is 1,000 watts, while electric cooling requires 2,800 watts. According to the principle of thermal equilibrium, at least 2,800 watts of heat is simultaneously generated. Combined with the 1,000 watts of electrical input, the actual heat output ranges from 3,000 to 4,000 watts. This heat is transferred to an insulated water tank, and the power consumption is only one-fourth that of an electric water heater (even if an electric water heater had 100% thermal efficiency, 1,000 watts of electrical input would yield only 1,000 watts of heat).

Air-source heat pump water heaters do not require sunlight, so they can be installed indoors or outdoors. Once the water in a solar water heater is used up, it is difficult to produce hot water immediately. If electric reheating is required, it takes a long time, whereas an air-source heat pump water heater can operate under pressure 24 hours a day, provided there is air and the temperature is above 0°C.

As a result, even after using up one tank of water, the air-source heat pump water heater can produce another tank of hot water in about an hour. At the same time, it fundamentally eliminates safety hazards such as electric leakage and dry burning in electric water heaters, as well as harmful gas emissions from gas water heaters. It overcomes the drawbacks of solar water heaters—such as inoperability on cloudy or rainy days and installation difficulties—and offers numerous advantages, including high safety, high energy efficiency, a long service life, and zero toxic emissions. The service life of an air-source heat pump water heater generally ranges from 15 to 20 years.

Daily maintenance of air-source heat pump water heaters is also crucial, as it directly impacts the unit’s lifespan; therefore, it must be taken seriously. It is often said that 10% of quality depends on the product itself, while 70% depends on installation. Thus, when installing the unit, choose the location carefully. Avoid piling clutter around the unit to prevent blocking the air inlets and outlets. The area surrounding the unit must remain clean and dry, with proper drainage and adequate ventilation.

Air-Source Heat Pump Water Heater

Ensure the water pump is properly protected from water to prevent the motor from being damaged by water immersion. In severe cases, this can damage the main unit’s circuit board, affecting the entire central hot water system.

Since air-source heat pump water heaters absorb heat from the air, the evaporator must be cleaned regularly to prevent reduced heat absorption capacity, frequent freezing of the unit, increased power consumption, and system malfunctions.

Regularly check the air-source heat pump water heater’s makeup water supply, tank safety valve, and circulation filter to ensure they are clean. This prevents reduced water circulation, which can affect the unit’s heating capacity and operational reliability.

Periodically inspect the air-source heat pump water heater to ensure the power connection is secure and wiring is tight. Repair any damaged components immediately to prevent accidents during use.