Operation CHARM: Car repair manuals for everyone.

Hose/Line HVAC: Service Precautions

Precautions on Servicing Refrigerant Line





- When connecting hoses and pipes, apply a few drops of compressor oil (refrigerant oil) to seats of coupling nuts and O-ring.
- Never use heat for bending pipes. When bending a pipe, try to make its bending radius as slight as possible.
- Keep internal parts of air conditioning free from moisture and dirt. When disconnecting any line from system, install a blind plug or cap to the fitting immediately.
- When tightening or loosening a fitting, use two wrenches, one for turning and the other for support.
- Tighten bolts to specified torque.

Tightening torque
Refrigerant line bolt: 12 Nm (1.2 kg-m, 9.0 lb-ft)


- Route drain hose so that drained water does not make any contact to vehicle components.