Thermal conductivity is a material’s ability to conduct heat through itself, measured in BTU per hour per foot per degree Fahrenheit. In HVAC applications, thermal conductivity determines how effectively heat transfers through insulation, piping, and heat exchanger materials. Materials with high thermal conductivity transfer heat quickly, while those with low conductivity provide better insulation.
Common Material Values
Copper has a thermal conductivity of approximately 226 BTU per hour per foot per degree Fahrenheit, making it ideal for heat exchanger tubes. Aluminum conducts heat at roughly 128 BTU per hour per foot per degree Fahrenheit. Fiberglass insulation provides thermal conductivity around 0.25 BTU per hour per foot per degree Fahrenheit, offering superior insulation performance for pipes and ductwork.
System Performance Impact
Higher thermal conductivity in heat exchanger materials improves energy transfer efficiency, allowing smaller, more compact equipment designs. Conversely, insulation materials with lower thermal conductivity values minimize unwanted heat loss or gain in refrigerant lines and ducts. Selection of materials based on thermal conductivity directly affects system efficiency, operating costs, and overall performance reliability.