How to Refill Refrigerant in a Car Air Conditioner?
3 Answers
Car air conditioner refrigerant refilling method is: 1. Prepare tools and materials such as car refrigerant recovery and refilling machine, refrigerant, etc.; 2. Connect the car refrigerant recovery and refilling machine pipelines to the car air conditioner's high and low pressure pipes; 3. Perform vacuum extraction on the car air conditioner; 4. Set the refilling capacity, time, and type on the refrigerant recovery and refilling machine; 5. The refrigerant recovery and refilling machine will automatically start adding refrigerant. Functions of car air conditioner: 1. Achieve cooling effect through continuous circulation and transformation of refrigerant; 2. Draw in fresh external air for ventilation and air exchange, preventing window fogging; 3. Use engine coolant, waste heat, or heat generated by a burner as a heat source for heating, which is then blown into the car by a blower to raise the temperature and achieve heating effect; 4. Remove dust, odors, smoke, and toxic gases from the car air, making the air fresh, and humidify the car air to increase relative humidity.
When helping out at repair shops, I've seen many people recharge refrigerant themselves, and the method is actually quite straightforward. First, start the car and turn the AC to maximum cooling mode with high fan speed to get the system running. Then prepare the R134a refrigerant can and recharge kit, including a pressure gauge and connecting hose. Locate the low-pressure service port in the engine bay—usually a small blue valve or one labeled "L"—remove its cap, and attach the hose. During recharge, slowly invert the refrigerant can while monitoring the pressure gauge; standard readings are around 35-45 PSI in summer and slightly lower in winter. Avoid adding too quickly or overfilling to prevent pipe bursts. After finishing, check for leaks by applying soapy water to connections and watching for bubbles. The tools cost less than 100 yuan online, but first-timers should have a friend guide them to avoid wasting refrigerant or damaging the system. Finally, test the AC to feel the cooling effect—if there's no improvement, the issue might be with the compressor or a leak, requiring professional inspection.
I've been repairing my car's air conditioning for several years. The basic steps are: start the engine, set the AC to maximum cooling with full fan speed, prepare the R134a refrigerant can and charging kit. The low-pressure port is usually located on the thin pipe near the headlight with a blue marking. After connecting the pressure gauge, slowly turn the refrigerant can valve to charge, and stop when the pressure reaches 35-45 PSI. After charging, check for leaks - if you smell oil or notice sticky connections, address them immediately. Aging refrigerant reduces efficiency, so it's best to replace it every two years for stronger cooling and better fuel efficiency. DIY saves money, but be aware that ambient temperature affects pressure values - it's recommended to work during daytime and avoid rainy days. The tools aren't complicated; you can get them for just tens of RMB on Taobao. Doing it yourself is fun and helps you learn new skills.
