Refrigeration piping materials for halocarbon (Freon) refrigerants For systems using common halocarbon refrigerants (e.g., R-12, R-22, R-134a), which piping material is generally preferred for refrigerant lines?

Introduction / Context:
Piping material selection in refrigeration depends on compatibility with refrigerant and oil, corrosion resistance, ease of joining, pressure capability, and cleanliness. Halocarbon (Freon-family) systems dominate comfort cooling and many commercial applications.

Given Data / Assumptions:

• Closed vapor-compression system with halocarbon refrigerant and mineral or POE oils.
• Standard pressure ranges for comfort cooling and medium-temperature applications.

Concept / Approach:
Deoxidized, high-phosphorus copper (Type L or K) tubing is widely used because it is readily brazed, cleanable, corrosion-resistant in typical HVAC environments, and compatible with halocarbons and oils. It also withstands common operating pressures and allows good leak-tight joints.

Step-by-Step Solution:

Verification / Alternative check:
Manufacturer installation standards specify copper tubing for suction, liquid, and discharge lines; steel is reserved more often for large ammonia systems or very high-pressure CO2 transcritical lines.

Why Other Options Are Wrong:
Brass is heavier and mainly used for valves/fittings, not full line runs. Steel is common with ammonia or industrial duties but less convenient for halocarbons in smaller systems. Aluminium and PVC lack the pressure/compatibility and joining robustness required.

Common Pitfalls:
Using soft solder instead of proper brazing alloys for high-pressure or high-temperature segments; always follow code requirements and purge with inert gas while brazing.

Final Answer:

copper