How to Add Refrigerant to a Car Air Conditioner?

[VanFinn]

There are two methods for adding refrigerant to a car air conditioner. One is the high-pressure side charging, which is suitable for charging after leak detection and vacuuming. Note that this method cannot be used with the compressor running, and the engine must be off, with the refrigerant canister required to be inverted. The other method is low-pressure side charging, where gas is added. This method is characterized by a slower charging speed and is typically used for replenishing refrigerant. Steps for high-pressure side refrigerant charging: 1. After the system is vacuumed, close the high and low-pressure manual valves on the manifold pressure gauge. 2. 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 pressure gauge hose to allow gas to escape for a few minutes, then tighten the nut. 3. Fully open the high-pressure side manual valve and invert the refrigerant canister. 4. 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 pressure gauge, then remove the gauge. When charging refrigerant from the high-pressure side, the engine must be off (compressor not running), and do not open the low-pressure manual valve on the manifold pressure gauge to prevent hydraulic shock. Steps for low-pressure side refrigerant charging: 1. First, connect the manifold pressure gauge to the compressor and refrigerant canister. 2. Open the refrigerant canister and loosen the nut on the manifold pressure gauge until you hear the sound of refrigerant vapor flowing, then tighten the nut to expel air from the injection hose. 3. Open the low-pressure manual valve to allow refrigerant to 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 conditioner switch, and set the blower switch and temperature control switch to maximum. 5. Open the manual valve on the manifold pressure gauge to allow refrigerant to continue entering the refrigeration system until the specified amount is reached.