Auto A/C Terms - Glossary
Discharge A/C System

Whenever servicing auto A/C system or changing components, the A/C system has to have the refrigerant removed so that the system can be opened. Removing all or part of the refrigerant from the A/C system is commonly referred to as discharging the A/C system.

According to older service practice, this was accomplished by opening one or both of the control valves on the manifold gauge set attached to the A/C system, and allowing the refrigerant to escape to atmosphere slowly.

With global environmental issues of ozone depletion and global warming, refrigerants should no longer be released to atmosphere, and in fact, in most countries, it is illegal to release refrigerants to atmosphere. For that reason, when discharging the A/C system or removing refrigerant, that refrigerant is now captured and stored. In a lot of cases, that captured refrigerant is recovered or recycled using machines that will filter any contaminants out and remove any oil A/C compressor oil that may be in the refrigerant. Once recycled, that refrigerant can then be used once again in the same, or another, auto A/C system.