Air-energy heat pump unit is one of the best equipment for exploiting and utilizing energy at present, and it is a new generation of hot water making equipment after boiler, gas water heater, electric water heater and solar water heater. With the development of economy, in the environment of increasingly tight global energy supply and increasingly prominent environmental protection problems, in order to achieve the goal of carbon neutrality in 2060, air-energy heat pump units have been recognized by users with many advantages such as high efficiency, energy saving, environmental protection, safety, comfort and convenient installation.
Further Read
What is heat pump?
The biggest advantage of air energy heat pump unit technology is economy and energy saving, because it has high energy efficiency, it only needs to consume a part of electric energy, and it can get 3-4 times as much heat energy as it consumes. The optimized COP value of air energy heat pump is generally between 2.3 and 3.0, which is easy to meet the requirements. At present, air energy heat pump hot water technology has been widely used in the field of building water supply and drainage, such as central hot water supply in hotels, guesthouses, schools and factories.
I.Project Overview
This project is the central heating project of Hengshui Base. The building area of this office building is 6535.70m2, with three floors above ground and a building height of 13.35m. The first floor is 4.5m high, the second and third floors are 4.2m high, and the total heating area is about 5131m2. The terminal air conditioning equipment adopts fan coil units to realize cooling in summer and heating in winter.
II.Local climate
Hengshui belongs to the continental monsoon climate zone, which is warm and semi-arid. The climate is characterized by four distinct seasons, with great differences in cold, warm, wet and dry. Affected by southerly airstream at the edge of Pacific subtropical high in summer, the tidal temperature is hot and the precipitation is concentrated; in winter, affected by northwest monsoon, the climate is dry and cold, with few rain and snow; in spring, it is dry, rainy and windy, and the temperature rises rapidly; in autumn, it is sunny and rainy. The annual average temperature is 12.5℃, the coldest in January, with an average of -5℃, and the hottest in July, with an average of 23℃, with an average annual rainfall of 500 mm.
III.Design value
Outdoor design parameters of Hengshui, Hebei
Architectural interior design parameters
| Season | Temperature（℃） | Relative humidity |
| Summer | 24-28 | 55%-65% |
| Winter | 18-22 | 30%-40% |
IV.Project Calculation
The cooling load in summer is greater than the heating load in winter, so the equipment selection is calculated according to the cooling load in summer. According to the experience, 12 ultra-low temperature air energy heat pump units were initially selected.
V.Equipment selection
The cooling load in summer is greater than the heating load in winter, so the equipment selection is calculated according to the cooling load in summer. According to the experience, 12 ultra-low temperature air energy heat pump units were initially selected. According to the test report data, when the dry/wet bulb temperature is 35/24 degrees and the inlet/outlet temperature is 12/7 degrees, the refrigerating capacity of the ultra-low temperature heat pump unit is 60kW. Then the total refrigerating capacity of the initial number of heat pumps is 60×12=720kW/h>691.3kW/h (air conditioning refrigeration load), then the initial 12 air source heat pump units basically meet the air conditioning refrigeration requirements. In view of the mirror layout of the east and west of this building, and the east and west parts belong to the workplaces of different departments, for the convenience of management and operation, the system of this project has also been designed as a mirror image, and six air source heat pumps are responsible for heating and cooling in each district. In the choice of indoor terminal, because this building is an office building, the floor height is more than 4m, but it involves the ceiling, and the actual installation height of the wind disk is about 3m. The wind disk is also used for convenience and energy saving. The whole project uses a system, and the overall cost can be controlled.
