What type of insulation material is commonly used for refrigerant lines?

Closed-cell foam insulation is commonly used for refrigerant lines due to its excellent thermal resistance and moisture barrier properties. This type of insulation has a structure where the cells are closed, which helps to prevent condensation from forming on the surface of the refrigerant line. When moisture seeps into insulation materials, it can lead to corrosion of the metal and other problems, such as reduced efficiency and potential system failures. Closed-cell foam is also effective at minimizing heat transfer, ensuring that the refrigerant maintains its intended temperatures while flowing through the lines.

In contrast, fiberglass insulation is typically better suited for applications with less concern for moisture and may not provide the same level of protection against condensation as closed-cell foam. Open-cell foam insulation is more breathable and may allow moisture to enter, which is not ideal for refrigerant lines. Plastic wrap does not offer adequate thermal insulation and is generally ineffective for this application. Therefore, closed-cell foam insulation is preferred for refrigerant lines due to its efficiency in handling thermal insulation while preventing moisture issues.