How to Refrigerant Recharge?
2 Answers
The steps for refrigerant recharge are: 1. Prepare refrigerant of the same model as required; 2. Prepare qualified refrigerant recharge tools; 3. Connect the car air conditioning system with the adapter of the recharge tool; 4. Perform vacuuming; 5. Proceed with refrigerant recharge. The properties required for refrigerant are: 1. Possess excellent thermodynamic characteristics to ensure high cycle efficiency within the specified temperature range; 2. High heat transfer coefficient, low viscosity, and small density; 3. Good compatibility with lubricating oil; 4. Safety requirements include being non-toxic, non-irritating, non-flammable, and non-explosive; 5. Good electrical insulation properties.
Last time I tried adding refrigerant to my old Jetta myself and it was a nightmare, so now I just go to the repair shop. The whole process requires specialized tools like pressure gauges and vacuum pumps. First, you have to evacuate all the residual refrigerant from the system, otherwise mixing old refrigerant will affect performance. Then vacuum for at least half an hour - this step is critical, as skipping it can leave moisture in the AC system that will freeze and block the pipes. When refilling, pay attention to the refrigerant type: R12 for older cars and R134a for newer ones, with the charging amount specified on the engine compartment nameplate. Finally, start the AC at maximum fan speed and monitor the pressure gauges - around 2.5bar low pressure and 15bar high pressure is ideal. Remember to wear goggles throughout the process as refrigerant spray can cause frostbite to the eyes.
