Refrigerant - Genetron® 408A

honeywell Genetron® 408A is an alternative retrofit refrigerant designed for low and medium-temperature refrigeration systems that use CFC-502. Systems where Genetron® 408A is suitable for use include: supermarket freezer cases, reach-in coolers, display cases, and ice machines. Genetron® 408A is a ternary blend of HCFC-22, HFC-125, and HFC-143a. As Genetron® 408A contains a hydrochlorofluorocarbon (HCFC), a chemical controlled by law, service technicians should keep in mind that regulations restrict the use of HCFC-containing refrigerants and dictate the ultimate use of HFCs (hydrofluorocarbons).

Where feasible, the preferred retrofit for CFC-502 is an HFC such as Genetron® 507. Genetron® 507 is a non-ozone-depleting refrigerant that is increasingly being used in many OEM applications. In some cases, however, retrofitting with Genetron® 507 may be difficult because nearly all of the mineral oil in the systems must be removed. For these instances, an interim-service fluid such as Genetron® 408A may be preferred. Genetron® 408A is not a "drop-in" replacement for CFC-502. As such, service technicians must acquaint themselves with the proper service procedures to perform each retrofit effectively. Two key points to be aware of are:

  • Mineral oils, which have been used traditionally with CFC-502, are much less miscible with Genetron® 408A than with CFC-502. Therefore, to get a good oil return with an evaporating temperature lower than -29°C, the proper lubricant to use is at least a 50% mixture of mineral oil and alkylbenzene.
  • Genetron® 408A is a blend that can segregate. For this reason it must be only liquid charged from the cylinder into the systems.