For refrigerant, we are not unfamiliar, in the home refrigerator, air conditioning and other places can see it, car air conditioning is also, refrigerant from the gaseous state into a liquid state will release a lot of heat. But in the liquid state into a gaseous state will absorb a lot of heat, air conditioning cooling and heating is because it has the characteristics and achieves. So today, we look at the correct way to refill the car refrigerant and tutorial.
Car Refill Refrigerant Tutorial
It is estimated that many people think that the refrigerant is only liquid. In fact, the refrigerant also has a gaseous state, two different states of the refrigerant in the filling also has a difference, liquid refrigerant regulations can only be filled through the high-pressure end, which is safer, faster, suitable for pumping after the first filling, note that the liquid refrigerant must be filled upside down; gaseous refrigerant must be filled through the low-pressure end, due to the slow filling speed, suitable for supplementary use.
Since the two states of refrigerant charging methods are different, let’s describe their correct charging methods, respectively.
Steps of refrigerant refilling method at the high-pressure end：
- 1. When the system is evacuated, close the high and low-pressure manual valves on the manifold pressure gauge.
- 2. Connect one end of the middle hose to the connector of the refrigerant tank charging valve. Open the refrigerant tank opening valve, unscrew the nut on one end of the manifold pressure gauge hose, let the gas overflow for a few minutes, and tighten the nut.
- 3. Unlock the manual valve on the high-pressure side to the fully open position and turn the refrigerant tank upside down.
- 4. Inject the specified amount of liquid refrigerant from the high-pressure side. Close the refrigerant tank charging and high-pressure manual valves on the manifold pressure gauge, then remove the gauge. When charging refrigerant to the system from the high-pressure side, the engine is not started (compressor is stopped), do not unscrew the low-pressure manual valve on the manifold pressure gauge to prevent hydraulic shock.
Low-pressure side refrigerant charging steps:
- 1. Firstly, connect the manifold pressure gauge with the compressor and the refrigerant tank
- 2. Open the refrigerant tank, loosen the nut of the middle injection hose on the manifold pressure gauge until you hear the sound of refrigerant vapor flow, then tighten the nut to discharge the air in the injection hose.
- 3. Open the low-pressure manual valve and let the refrigerant enter the refrigeration system. When the system pressure reaches 0.4MPa, close the low-pressure manual valve.
- 4. Start the engine, turn on the air conditioning switch, and set the blower and temperature control to the maximum.
- 5. Open the manual valve on the manifold pressure gauge and let the refrigerant continue to enter the refrigeration system until the charge amount reaches the specified value.
- 6. After filling the system with the specified amount of refrigerant, observe if there is no bubble and no excess refrigerant from the sight glass. Then, turn the engine speed to 2000r/min and the blower air volume to the highest grade. If the pressure on the low-pressure side of the system should be 0.147~0.192MPa and the pressure on the high-pressure side should be 1.37~1.67MPa.
Operation skill: After fluorine filling, close the low-pressure manual valve on the manifold pressure gauge, close the injection valve installed on the refrigerant tank, stop the engine, remove the manifold pressure gauge from the compressor, and move quickly when removing it to avoid excessive refrigerant leakage.
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