reblog

Which aspects can be observed whether the refrigerant charge is appropriate

Pressure gauge observation: For example, R12 refrigerant system, the engine speed is 2 000r/min, the fan speed is the highest, and the temperature is 21～32℃, the pressure on the low pressure side of the system should be 0.15～0.20MPa, and the pressure on the high pressure side. It should be 1.45 ~ 1.50MPa. For R134a refrigerant system, the pressure on the low pressure side of the system should be 0.15 to 0.25 MPa, and the pressure on the high pressure side should be 1.37 to 1.57 MPa.

Observation from the liquid storage window on the liquid storage dryer: When the system is working, the liquid viewing window is clear and free of bubbles, and liquid flow can be observed.

The amount of Refrigerant charging pipe  in the system and the signs corresponding to the observation window are shown in Table 1-3.

Table 1-3-4　 the amount of refrigerant in the system and the signs corresponding to the observation window

Refer to the manual provided by the manufacturer to fill in.

Precautions

Since there are currently two types of refrigerants commonly used in automotive air-conditioning refrigeration systems, R12 and R134a, the type of refrigerant used in the system must be ascertained before filling.

Pay attention to emptying the air in the connecting hose before filling the refrigerant, especially when filling with a small tank, the air in the connecting hose must be drained after each tank change.

After filling, take care to prevent the residual refrigerant in the hose from damaging eyes and skin when removing the hose

The refrigerant will inevitably not decrease after the automobile air conditioner is used for a long time. The high pressure Car Refrigerant charging pipe end charging method means that the refrigerant is added to the system from the high pressure end of the air conditioning system.

R12, R134, R410 refrigerant and liquid tricolor tube
① As shown in the figure, connect the manifold pressure gauge group with the system maintenance valve and refrigerant tank.
② Use the refrigerant to remove the air in the connecting hose. The specific method is: first close the high and low pressure manual valves, disconnect the high pressure end inspection valve and the hose connection, then open the high pressure manual valve, and finally open the valve. When the refrigerant gas is discharged from the Charging Pipe , quickly connect the hose to the maintenance valve and close the high-pressure manual valve. Use the same method to remove the air in the connecting hose at the low pressure end, and then close the high and low pressure manual valves and the valves on the refrigerant cylinders.
③ Put the refrigerant tank upside down on the scale and record the initial mass.
④ Open the valve on the refrigerant bottle, and then slowly open the high-pressure manual valve. The refrigerant is injected into the system. When the scale indicates that the specified quality is reached, the refrigerant valve is quickly closed.
⑤ Close the high-pressure manual valve and the filling ends.