EVI Low Temperature Cold Climate Heat Pump Air Source R410A

R410A EVI Low Temperature Cold Climate Air Source Heat Pump Constant Hot Water

EVI low temperature air-source heat pump is a kind of heating equipment widely used in the cold areas of Europe. Because of the Enhanced Vapor Injection (EVI) compressor technology and high-efficiency eco-friendly refrigerant, EVI heat pumps can work stably in cold regions where lowest air temperature reaches -25℃

The control method of this low-temperature heat pump system includes the following steps: A. Turn on the compressor, and after the main circuit runs for t1 time until the refrigerant operation in it is close to steady state, run the jet enthalpy increasing circuit; B. Judging the exhaust during the heating process Whether the air temperature T row is greater than the preset maximum exhaust temperature T row max, if yes, go to step C, otherwise, go to step E; C. Inject the supercooled refrigerant liquid directly into the middle pressure cavity of the compressor to reduce the exhaust Temperature T row; D. Determine whether the exhaust temperature T row is greater than the preset maximum exhaust temperature T row max-the return difference value △T row of exhaust temperature drop, if yes, go to step C, otherwise, go to step E; E, The system is heated to the set temperature and exits. This design solves the problem that the existing low-temperature heat pump system cannot reach a stable state as soon as possible in the early stage of operation, and the refrigerant distribution of the main circuit and the injection circuit may be uneven, and the reliability of the compressor is improved.

Features of R410A EVI Low Temperature Cold Climate Air Source Heat Pump Constant Hot Water

Copeland ZW series compressor (structure)
Floating seal—specially designed to adapt to high compression ratio; fixed scroll and dynamic exhaust valve—specially designed to adapt to high pressure difference; EVI—control safe exhaust temperature; motor—high insulation class motor
① Copeland ZW series compressor (extra wide operating range)
Copeland ZW series compressors (air jet enthalpy)
Key components-S&C shell and tube heat exchanger
②Key components-S&C shell and tube heat exchanger (performance characteristics)
A. Compact structure and high efficiency:
The high-efficiency heat exchange tube is used inside, and its heat exchange area is 3.7 times that of a bare tube. The fins outside the tube and the inner ridge of the tube can cause strong turbulence of the refrigerant and cooling water, so the heat transfer efficiency is greatly improved.
B. Countercurrent arrangement:
The countercurrent arrangement of the cooling water circuit and the refrigerant circuit can ensure the supercooling degree of the outlet refrigerant and improve the system efficiency accordingly;
C. Adapt to the large temperature difference between inlet and outlet water:
Reduce the amount of condensate circulation, correspondingly reduce the size of the condensate water pipe and the size of the circulating pump; the lower pressure drop on the water side reduces the pump power and operating costs;
D. Can be frozen and cleaned:
Spiral coils make the water flow smoothly and facilitate the implementation of freezing cleaning; freezing cleaning can shorten the downtime and avoid the use of chemicals;
E. The clearance between the refrigerant circuit and the shell is small:
Will not cause lubricating oil to stay, can ensure oil return;
F. The water coil has no internal joints:
The leakage factor is reduced, and the 5MPa pressure test ensures the safe and stable operation of the heat exchanger.
③) Key technology-control system
Electronic expansion valve control technology for steam injection to increase enthalpy;
Limit exhaust temperature control technology;
The superheat control technology of the electronic expansion valve of the main circuit;
The water temperature follows the ambient temperature operation control technology.
4 Analysis of energy saving and economic indicators
①The third party (SGS) test report:
Application occasions
① Purpose:
◆Domestic hot water, high requirements for outlet water temperature ◆Water for bathing, washing, cleaning, sauna, and industrial use;
◆Heating, high requirement of outlet water temperature ◆Heat sink, fan coil unit; ◆Comfortable heating, low requirement of outlet water temperature
◆Floor heating.