Westron R404a Refillable Gas

Physical and Chemical Properties

Chemical NamePentafluoroethane,
Chemical FormulaCH2FCF3
Molecular Weight102.02 g/mol
FormLiquefied Gas
Melting Point-101 °C (-150 °F)
Boiling PoinT at 1.013-26.2 °C (-15.1 °F)
Vapor Pressure5,915 hPa at 21.1 °C (70.0 °F)


Westron® Refrigerants 404A (HFC-404A) is a non-ozone depleting compound designed to serve as a long-term alternative to Westron® Refrigerants 502 (CFC-502) and Westron® Refrigerants 22 (HCFC-22) in low and medium temperature commercial refrigeration applications. Applications where Westron® Refrigerants 404A is a suitable retrofit refrigerant include supermarket freezer cases, reach-in coolers, display cases, transport refrigeration and ice machines.

Westron® Refrigerants 404A has been designed as a substitute to Westron® Refrigerants 502, but it is not a drop-in replacement. Mineral oils and alkylbenzene lubricants, which have been used traditionally with Westron® Refrigerants 502, are immiscible with Westron® Refrigerants 404A. Service technicians should consult the original equipment manufacturer for the recommended lubricants.

Westron® Refrigerants 404A is a blend. For this reason it is essential that systems be charged only with liquid from the cylinder, not vapour. Vapour-charging Westron® Refrigerants 404A may result in the wrong refrigerant composition and could damage the system.