• News
• Industry News

R410a Refrigerant Characteristics, System Vacuum and Refrigerant Charging Procedure Interpretation

First, R410a is liquefied gas at room temperature, and must be protected according to the high-pressure gas management method; Do not let the R410a container fall, suffer a strong collision or roll. Store and use in a place with air circulation; R410a gas is heavier than air, easy to settle in a low place, such as gas leakage, may cause human hypoxia; Such as refrigerant leakage in the room, such as open fire, electric spark, will form toxic gas, should be ventilated in time.
Second, the pressure of R410a is about 1.6 times higher than that of R22 refrigerant, requiring the use of R410a special tools, materials and accessories:
(1)Special tools include: vacuum pump with electromagnetic check valve; Pressure gauge, charging hose; Electronic filling scale; Copper tube flaring equipment; Leak detector, corresponding to R410a refrigerant to detect hydrogen leakage;

(2)Special materials include: refrigerant charging tank; High-quality thickened copper pipe that is easy to bend, such as hanging wall thickness of 2P and below up to 8mm; The refrigeration system has high requirements for cleanliness, and the pipes that have been used can not be used, and the new pipes must be guaranteed during construction.

(3)Special accessories include: compressor, four-way valve, globe valve, check valve, solenoid valve, expansion valve, filter dryer;
Three, the refrigeration system vacuum
(1)Necessity
1, the use of vacuum pump from the refrigeration system, the air, water and impurities out.
2, R410a is insoluble in water, a very small amount of water in the refrigeration system will still cause freezing, that is, ice blocking;
3, the refrigerant oil of the compressor is esterified oil or ether oil, which has strong hygroscopic property, and it is easy to precipitate after mixing with foreign matter, resulting in the failure of the refrigeration system;
4, do not mix the air into the refrigeration system circulation pipeline. If mixed with air will lead to high pressure abnormal refrigeration system, or even rupture;
The steps of vacuumi

1, the refrigeration system pipeline installation is completed, after the air tightness test, before filling the refrigerant, the pipeline system needs to be vacuumed.
2, check the refrigeration system, if there is pressure, should be eliminated in the check joint;
3, the special pressure gauge connected to the operating valve, the split machine only 1 operating valve; Multi-line has 2 operating valve interfaces, be sure to access the liquid side charging port.

4. Start the vacuum pump to vacuum, when the compound pressure gauge shows -0.1MPa(-76cmHg), the vacuum pump continues to operate for more than 15 minutes, close the valve on the pressure gauge and place it for more than 30 minutes, the vacuum gauge pointer does not rise; If the vacuum gauge pointer rises, it means that there is a leak in the system, please repair the leak point, re-vacuum operation; 5, do not use the compressor to vacuum;
6, do not operate the compressor in the vacuum state; Fourth, the refrigeration system charging refrigerant:
(1)The type of refrigerant must be confirmed before operation. In the air conditioning system using R410a refrigerant, only R410a refrigerant can be used;
(2)Do not use R410a pressure to discharge air without vacuuming;
(3)In case of R410a leakage, all discharge and re-vacuum to avoid insufficient or excessive refrigerant dose;

(4)According to the weighing charging method:

1. Connect the refrigerant tank to the machine, first connect the filling hose to the refrigerant tank, open the refrigerant tank valve for a few seconds, and observe that when the filling hose has gas blowing out, connect to the pressure gauge; The amount of injection is marked according to the equipment nameplate or manual requirements, and the weight of the refrigerant tank of the electronic liquid weighing scale is recorded;
   2, from the liquid pipe access, open the input hose valve, refrigerant is from the refrigerant tank into the machine, pay attention to the speed to be slow;
   3, if added less can be added, but added more must be all released!
   4, if the amount of charge is not reached, the refrigerant is stagnant, start the compressor and then add, and close the valve after reaching the amount of refrigerant;
   (5)Remove the pressure gauge, reset the valve port cover tighten;
   (6)Use the leak detector to check whether there is air leakage along the piping; Five, construction precautions:
   (1) In the process of welding, it is necessary to ensure that nitrogen is circulated in the distribution pipe while welding.
   (4)R410a is a kind of simulated azeotropic mixed refrigerant, which is added by liquid method when adding refrigerant;
   1, the pink refrigerant tank upside down, pay attention to the speed to be slow, to prevent the press from returning liquid;
2. If the pot marked with siphon does not need to be inverted, it can be fluoridated upright;

END!