Efficient operation at low ambient temperature is a technical difficulty for Commercial Heat Pump

Efficient operation at low ambient temperature is a technical difficulty for Commercial Heat Pump

At present, the technical requirements of commercial projects for commercial aircraft are getting higher and higher, COP is from 2.1 to 2.2 or even 2.3, and IPLV has grown from 2.4 to 2.6 or even higher. This not only requires the application of EVI technology to be thorough, but also requires optimization of the unit system, defrost technology and control performance. The technical barriers faced by commercial aircraft are mainly the application of geographical restrictions. At present, the lowest application ambient temperature of commercial units is -30 °C (some manufacturers advertised -35 ° C, but the reliability has yet to be verified), and the reliable application in colder regions is a The problem, and the lower the temperature, the worse the energy efficiency of the unit.

There are three current solutions: one is to apply two-stage compression or multi-stage compression to increase the compression ratio; the other is to apply carbon dioxide refrigerant; the third is to use multiple energy complementary solutions, such as air energy + solar energy, air energy + electric boiler, etc. , can be considered in multiple directions.

The technical barriers of commercial machines are mainly defrosting problems at low ambient temperatures. Traditional defrosting technologies encounter many problems at low temperatures, such as frequent defrosting, frosting, and defrosting, which leads to the unit. The heating capacity is severely degraded or even unusable.

The application of commercial machines, especially in the northern region, has to overcome two problems: first, safe and efficient operation under low temperature conditions; second, defrosting technology. The commercial machine is applied to the large-scale heating project in combination with the operating characteristics of the air source heat pump. The air source heat pump heating is characterized by the higher the unit's water temperature, the lower the unit efficiency, and the lower the outdoor temperature, the lower the efficiency. And to manage the air source heat pump central heating must follow this operating characteristics.

In addition, as a large-scale heat pump central heating project, it is very important to build the energy efficiency ratio of the system operation. The implementation and maintenance management points of the heat pump central heating system are improved: zero, for large-scale communities, try to make several buildings or one A heating station in the building, let the main unit be placed as much as possible to avoid the cold island effect, affecting the unit operating efficiency; the main unit is placed as far as possible to improve the heat exchange efficiency; improve the management level and make the system the most suitable Heating at temperatures and reducing the energy consumption of the pump.