Hose/Line HVAC: Description and Operation

A/C Refrigerant System, Component Overview

Hoses and lines
The mixture of refrigerant oil (PAG oil) and refrigerant R-134a attacks some metals and alloys (for example, copper) and breaks down certain hose material. Use only hoses and lines which are identified with the lettering "R-134a."

Hoses and lines are secured with threaded connections. Always properly torque hose and line connections.