Brazing vs Soldering: Why Refrigerant Lines Get Brazed

Three brazing jobs in a row. First, a torch works a joint at the compressor inside an outdoor condenser with its panels opened. Next, a tech with a short dark beard brazes copper overhead near a furnace in a basement.

The last shot is the service valve on a condenser, wrapped in a wet rag while the flame works the joint beside it. That rag soaks up heat so the valve's internal seals don't cook. Each joint gets heated until the filler metal flows into the fitting and seals the copper.