1. The working temperature and pressure of the refrigerant should be moderate.
At atmospheric pressure, the evaporation temperature of the refrigerant should be low enough to meet the cooling temperature requirements.
At room temperature, the refrigerant should have a relatively low condensing pressure. When the condensation pressure is too high, the structural strength of the refrigeration system sealant is required to be higher. The general requirement for the condensation pressure of the refrigerant is 12*105-15*105Pa.
At room temperature, the refrigerant should have a high evaporation pressure, because if the pressure in the evaporator is lower than the atmospheric pressure, outside air can easily enter the cooling system through the gap, causing the pressure in the system to increase, reducing the cooling capacity and increasing power consumption. At the same time, moisture in the air can also cause harmful effects such as ice jams on the refrigeration system.
2. The refrigerant should have a large cooling capacity per unit volume.
For refrigeration equipment of the same specification, when the cooling capacity per unit volume of the refrigerant is larger, a larger cooling capacity can be obtained.
Under the same working conditions, when the cooling capacity is constant, the cooling capacity per unit volume of refrigerant is larger, which can reduce the amount of refrigerant in the system and reduce the size of the compressor.
3. The critical temperature of the refrigerant should be high and the freezing point should be low.
The critical temperature is high, and the refrigerant is easy to condense and weigh the liquid at normal temperature; the freezing point is low, which can produce a lower temperature, expand the refrigerant temperature range, reduce throttling losses, and improve the refrigeration coefficient.
4. The viscosity and density of the refrigerant should be as small as possible.
Low viscosity and density can make the flow resistance of the refrigerant cycle in the system smaller, reduce cycle power consumption, appropriately reduce the diameter of the pipe, and allow the pipe to have a smaller bending radius (which is very important for reducing the pressure loss of the evaporator), At the same time, it also reduces the impact of the refrigerator on the valve group in the compressor. The compressor has a long service life.
5. The refrigerant has high thermal conductivity and high heat release coefficient
High thermal conductivity and heat release coefficient can appropriately reduce the structure of the heat exchanger in the refrigeration system and improve the heat transfer efficiency of the heat exchanger.
6.Other requirements for refrigerants
It is non-flammable, non-explosive, non-toxic, non-corrosive, affordable and easy to purchase.