How to Perform Pressure Testing on a Car Air Conditioning System?
2 Answers
Here’s how to perform pressure testing on a car air conditioning system: 1. Check the pressure in the car: First, rotate the needle valve on the DIY refill hose opener counterclockwise to its highest position, then screw the refrigerant can into the opener and tighten it. 2. Locate the low-pressure port: Typically, there’s a small blue or black cap under the hood on the left side with an "L" marked on it. Unscrew this cap. 3. Start the car engine and turn on the AC switch, setting the blower to maximum. Wait for three minutes, then connect the DIY hose to the car’s air conditioning low-pressure port. 4. Once the DIY hose is connected to the low-pressure port, the pressure gauge on the DIY hose will immediately show a reading. 5. At this point, the refrigerant refill for the car’s air conditioning system is complete. Simply tighten the "L" cap.
When I recharge my car's AC refrigerant myself, I usually buy an R134a refrigerant can and a connecting hose tool, which are all available online. First, locate the low-pressure port of the AC system in the engine bay, typically marked with a blue or black cap. Clean the area and attach the connector. Then, to ensure the system is clean, I use a rented vacuum pump to evacuate for about 30 minutes until the pressure gauge shows a vacuum. After evacuation, close the valve and slowly open the refrigerant can valve to let the refrigerant flow in. Meanwhile, start the car and turn the AC to maximum cooling, monitoring the pressure gauge to maintain a moderate value within the green zone. After filling, check the cooling effect—if it's not cold enough, there might still be leaks in the system. Remember, safety first: wear gloves and goggles because refrigerant can cause frostbite, and avoid leaks to protect the environment. DIY saves money, but beginners should be cautious.
