Why You Must Evacuate Air from a Car Before Charging the A/C with Refrigerant

One very important step in recharging your air conditioning system with refrigerant is vacuuming the whole system to eliminate any present air within the system. Avoiding this step if the system is empty can lead to issues and problems affecting your A/C’s performance. Here are six reasons why evacuating your car’s A/C system is necessary.

1. Contamination with Non-Condensable Gasses:

Air and other non-condensable gasses can enter your AC system over time. These gasses can cause problems like increased operating pressure, low cooling efficiency, higher compressor load, and damage to other parts of the A/C system. It is important to remove all these unwanted gasses to ensure the proper cooling performance of the A/C system.

2. Moisture Issues

Vacuuming the AC system doesn’t just remove unwanted air but also removes moisture. Moisture is the number 1 enemy of the air conditioner system. When moisture mixes with refrigerant, it forms highly corrosive hydrochloric and hydrofluoric acids that can corrode internal parts of the AC system. Another problem that can be caused by moisture is that it can freeze and block the essential parts like the expansion valve and capillary tube. This results in a blockage that can hinder refrigerant flow.

3. Inefficient Cooling

The unwanted air in your air conditioner system displaces the refrigerant, reducing its volume and purity. This can affect its properties to condense and transfer heat effectively. Cooling efficiency will be greatly affected, resulting in a longer time to cool the car’s interior. A longer wait time to reach the set temperature means that the compressor will work longer periods, leading to high fuel consumption. It is important to keep your AC system free from unwanted air that can affect your AC’s cooling performance.

4. Increased Wear

Low cooling efficiency translates to longer run time for the compressor. This increases wear on the compressor’s internal components. Refrigerant oil, used to lubricate the AC compressor, can also decline due to unwanted air in the system. Vacuuming or evacuating air and adding the correct amount of refrigerant oil can prevent these issues.

5. Potential for AC Component Failure

Uncondensable gasses can increase the operating pressure of the AC system. This can lead to components and seal failure that can cause your AC to break down. Following the correct procedure in recharging the refrigerant is important to prevent this.

6. Refrigerant Not Functioning as Expected

Refrigerants have certain properties that might be affected when mixed with unwanted air, especially their boiling and condensation properties. These properties can change, leading to the AC not cooling as efficiently as possible or struggling to keep a consistent temperature inside the vehicle.

Failing to evacuate the air from the AC system before recharging it with refrigerant, such as R134a, can result in a lot of problems. Always follow the correct procedure to avoid costly repairs and problems. This is to ensure that your AC system will work as efficiently and reliably as possible.