Air source heat pump water heater

Operating Principle of Air Source Heat Pump Water Heaters.

An air source heat pump water heater, also known as a heat pump water heater or air-to-water heat pump, is a "heat transfer" device that uses refrigeration principles to absorb heat from the air to produce hot water. By continuously circulating the refrigerant through the thermodynamic cycle of evaporation (absorbing heat from the environment) → compression → condensation (releasing heat) → throttling → re-evaporation, it transfers heat from the environment to the water.

The "air source heat pump water heater" absorbs low-temperature heat from the air, vaporizes it via a fluorinated medium, then compresses and pressurizes it using a compressor to increase its temperature. The compressed high-temperature heat is then transferred to the water through a heat exchanger to heat the water.

Key Components of a Heat Pump Water Heater.

Four Major Refrigeration Components: Evaporator, compressor, condenser, and throttling device.

Three Major Stabilizing Components: Liquid storage tank (for the compressor), expansion valve (capillary tube), and dryer (for moisture removal).

One Major Defrosting Component: Four-way valve.

Two Major Water Storage Components: Water tank and heat exchanger.

Air source heat pump water heaters do not require sunlight, so they can be installed indoors or outdoors. Unlike solar water heaters, which struggle to produce hot water immediately after the stored water is used up, and electric heaters, which take a long time to heat water, air source heat pump water heaters can operate under pressure 24/7 as long as there is air and the temperature is above zero degrees Celsius. Thus, even after using a full tank of water, the unit can produce another tank of hot water in about an hour. Additionally, it fundamentally eliminates safety risks such as electric leakage and dry firing in electric water heaters, as well as the production of harmful gases in gas water heaters. It overcomes the limitations of solar water heaters, which cannot be used on cloudy or rainy days and are inconvenient to install. It offers numerous advantages, including high safety, high energy efficiency, long lifespan, and no emission of toxic gases. The lifespan of an air source heat pump water heater typically ranges from 15 to 20 years.

The rapid development of the air source heat pump industry dates back to the 1940s and early 1950s. As early as 1743, European countries had a significant number of large-scale air source heat pumps. By 1948, domestic air source heat pump water heaters began to be mass-marketed. However, it is only in recent years that air source heat pump water heaters have become increasingly common in people's lives in China. As is well known, they offer many advantages: safety, energy savings, comfort, and environmental friendliness. But do air source heat pump water heaters have any disadvantages? What are their drawbacks? Below, we summarize the pros and cons of air source heat pump water heaters.

Advantages of Air Source Heat Pump Water Heaters

1. Energy Saving. Because the thermal efficiency of air source heat pump water heaters reaches 300%-500%, which is 4-5 times higher than that of conventional water heaters, the cost of heating water is very low, resulting in significant energy savings. The daily electricity cost for an air source heat pump water heater is around 1-2 yuan, saving about 70-80% on monthly electricity bills compared to conventional water heaters.

2. Convenience and Comfort. It provides hot water automatically and continuously 24 hours a day, regardless of weather conditions such as rain, snow, or cloudy days, making it even more convenient than typical solar water heaters.

3. Efficient Dehumidification. It can remove up to 6-8 kg of moisture per day, with even more noticeable effects during rainy and humid weather, making it particularly suitable for the damp climate of southern regions.

4. Low Noise. Air source heat pump water heaters use enclosed silent compressors and internal sound-absorbing materials, resulting in very low noise levels.

5. Environmentally Friendly. Since air source heat pump water heaters do not use gas, they produce no exhaust fumes and thus do not damage the ozone layer. Additionally, because they save electricity, every kilowatt-hour of electricity saved reduces carbon dioxide emissions by 1.5 pounds during power generation, further protecting the ozone layer. Therefore, using air source heat pump water heaters can help mitigate "global warming." They also help purify indoor air.

6. Safe. Air source heat pump water heaters do not use gas, completely eliminating the risk of carbon monoxide poisoning. They also do not use electric heating elements, eliminating the possibility of electric leakage, making them much safer.

7. Suitable for Multiple Users Simultaneously. When the temperature setting of an air source heat pump water heater reaches 55°C, it automatically heats to maintain a constant temperature. When hot water is used, cold water enters the system until the temperature drops to a certain level, at which point the system automatically restarts. It can continuously produce 100-700 liters of hot water at 45-55°C per hour. Tests show that each person requires about 42°C water temperature and 40-50 liters of hot water for a shower. An air source heat pump water heater can provide hot water for more than three people consecutively. However, since three people typically take about an hour to shower, the replenished hot water can be used by even more people.

8. Wide Range of Applications. Air source heat pump water heaters are suitable for: industrial production hot water; factory bathing and drinking water preheating; hospital washing and bathing hot water; school or private student dormitories, company employee dormitory showers; hotels, inns, and guesthouses with central hot water supply; bath centers, restaurant kitchens; beauty salons, kindergartens, and school drinking water preheating; household showers, bathtubs, Jacuzzis, and other hot water uses, especially for mid-to-high-rise apartments, villas, and users with high hot water demand; household floor heating, radiator heating, and fan coil heating; car washing, laundry, and all other domestic hot water needs.

9. Especially for high-rise residential buildings where energy-efficient water heaters (such as balcony-mounted solar water heaters) are mandatory, some properties cannot achieve sufficient sunlight due to narrow spacing between buildings, landscaping on lower floors, or architectural designs with unique facades or floor-to-ceiling windows on balconies. In such cases, air source heat pump water heaters can be installed to achieve energy savings comparable to solar water heaters.