Refrigerant

The working fluid in air conditioners and heat pumps. Refrigerant is a chemical (such as R‑410A, R‑134a, or newer low-GWP blends) that cycles through the system’s coils. It evaporates (absorbing heat) in the indoor evaporator coil and condenses (releasing heat) in the outdoor condenser coil. Different refrigerants have different properties; the choice affects efficiency and environmental impact. Refrigerant flow is controlled by expansion devices and compressors in the system.