What Refrigerant is Used in Car Air Conditioning?
2 Answers
The refrigerant used in car air conditioning is R134a. Refilling refrigerant in car air conditioning includes the high-pressure side refrigerant charging method and the low-pressure side refrigerant charging method, as detailed below: High-pressure side refrigerant charging method: After the system is vacuumed, close the high and low-pressure manual valves on the manifold gauge. Connect one end of the middle hose to the refrigerant canister injection valve. Open the refrigerant canister valve, then loosen the nut at one end of the manifold gauge hose to let gas escape for a few minutes, then tighten the nut. Open the high-pressure side manual valve fully and invert the refrigerant canister. Inject the specified amount of liquid refrigerant from the high-pressure side. Close the refrigerant canister injection valve and the high-pressure manual valve on the manifold gauge, then remove the gauge. When charging refrigerant from the high-pressure side, the engine should be off (compressor stopped), and do not open the low-pressure manual valve on the manifold gauge to prevent hydraulic shock. Low-pressure side refrigerant charging method: First, connect the manifold gauge to the compressor and refrigerant canister. Open the refrigerant canister and loosen the nut of the middle injection hose on the manifold gauge until you hear the sound of refrigerant vapor flowing, then tighten the nut to expel air from the injection hose. Open the low-pressure manual valve to let refrigerant enter the system. When the system pressure reaches 0.4 MPa, close the low-pressure manual valve. Start the engine, turn on the air conditioning switch, and set the blower switch and temperature control switch to maximum. Open the manual valve on the manifold gauge to let more refrigerant enter the system until the specified amount is reached. After charging the specified amount, observe through the sight glass. If there are no bubbles and no excess refrigerant, adjust the engine speed to 2000 rpm and set the blower to the highest speed.
As a long-time enthusiast following automotive developments, I find the evolution of car air conditioning refrigerants quite fascinating. Older vehicles commonly used R12, a Freon-based refrigerant, but it was phased out in the 1990s due to its ozone-depleting properties. The current mainstream choice is R134a, which is used in most vehicles and offers good cooling performance, though with higher global warming potential. Under new regulations, European and American markets are transitioning to R1234yf for new vehicles. This HFO-class refrigerant is more environmentally friendly with significantly lower global warming potential. If you own an older car, you might still be using R134a, but avoid mixing different types as system designs vary and could lead to leaks or damage. Regular AC system checks are essential, especially when cooling performance drops during summer, as it might indicate low refrigerant levels requiring recharge. Technological advancements continue to drive progress, and choosing the right refrigerant is crucial for environmental safety – always consult professionals to prevent mistakes.
