Frequently Asked Questions

• What copper fittings are typically used for HVAC refrigerant line connections?

  ACR-rated long-radius elbows, couplings, reducers, street ells, tees, flare nuts, and caps are common. Match the tubing OD and choose fittings suited to brazed or flared joints.

• How do I size and install K-Flex pipe insulation on copper lines?

  Match the insulation ID to the tube OD, dry-fit, then seal seams and butt joints with approved contact adhesive or tape. Protect outdoor runs from UV and mechanical damage.

• Are these accessories compatible with mini-split systems from Gree?

  Yes. Use ACR copper, fittings, and insulation that match the unit’s specified line sizes. Many mini-splits use small OD suction/liquid lines-always follow the manufacturer’s chart.

• What tools and materials are needed to braze or solder copper HVAC lines?

  A torch (air- or oxy-acetylene), silver brazing alloy, tube cutter/deburrer, emery cloth, nitrogen for purge and pressure testing, flux when required, and proper PPE.

• How much insulation thickness is recommended for suction lines to prevent condensation?

  Use 1/2 inch minimum in typical conditions; in warm or humid climates, 3/4 to 1 inch helps limit sweating and heat gain. Confirm local codes and equipment guidance.

• Can these fittings be used for both ACR and plumbing copper?

  Use refrigeration-grade ACR components for HVAC. Plumbing fittings are sized differently and are not cleaned/dehydrated for refrigerant service.

• Do I need flux or silver brazing alloy for joining refrigeration copper?

  Copper-to-copper joints are commonly brazed with silver-phos alloy without flux; copper-to-brass requires flux. Soft solder is generally not used on high-pressure lines.

• What safety considerations should I follow when working with copper and insulation on HVAC lines?

  Wear eye/hand protection, keep a fire watch, purge with nitrogen while brazing, ventilate, follow adhesive directions, and pressure test before charging the system.

• How do I prevent scale and oxidation inside the tube while brazing?

  Maintain a low nitrogen flow (typically 2-5 SCFH) through the tubing during brazing to prevent internal oxidation and keep the system clean.

• Can I reuse old flare nuts and fittings?

  Only if undamaged with perfect sealing surfaces. Best practice is to make a fresh flare and use new flare nuts, then torque to the equipment specification.