RS-24 (R426A)

The new Zero ODP Drop-in Refrigerant

  • Suitable for all applications including mobile air conditioning.
  • No need to change the existing lubricant avoiding expensive retrofit.
  • Avoids risks associated with a 'dirty retrofit' using R134a and mineral oil.
  • The use of RS-24 enables oil return to the compressor.
  • No hardware changes required.
  • Avoids the use of hygroscopic and costly synthetic lubricants.
  • Glide of less than 1°C.
  • Easy to recycle.
  • Lower discharge temperatures.
  • Zero ozone depletion potential.
  • Non-flammable.
  • An almost perfect performance match to replace R12.
  • The ideal replacement for R12 in vehicle air conditioning.
  • Available in returnable and disposable cylinders.
  • Suitable for new and existing plant and equipment.

Drop-in and long-term R12 replacement

RS-24 is an easy-to-use Drop-in replacement for R12, There is no need to change the existing lubricant in the system, thereby avoiding a costly retrofit. RS-24 also provides a long term solution to replacing R12 in most applications such as hermetic and semi-hermetic systems, domestic refrigerators, refrigerated transport, cold stores, cellar cooling, dairy chillers, vending machines and including mobile air conditioning.

The properties of RS-24 make it an almost perfect match for R12 with its compatibility for traditional and synthetic lubricants, similar performance, lower discharge temperature, non-flammability and relatively short atmospheric lifetime. Performance relative to R12 is illustrated in Charts 1, 2 and 3 (on subsquent pages - please follow the link at the bottom of this page). It is this combination of properties which makes RS-24 unique as a replacement for R12 on the market today.

RS-24 is also suitable as a replacement for R134a due to its higher capacity which can be particularly beneficial at high ambient temperatures. RS-24 is an excellent replacement for R12 and compatible with R134a automotive air conditioning systems.

Ashrae Number

RS-24 has been designated an Ashrae number of R426A with a classification of A1, which is low toxicity and nonflammable.

RS-24 Physical Properties

    RS-24 R12
Molecular weight   102.6 120.9
Boiling point (1 atm) °C - 28.6(1) -29.8
°F -19.5(1) -21.6
Temperature glide °C 0.5 0
Critical temperature °C 101.0 112.0
°F 213.8 233.6
Critical pressure kPa 4097 4116
psia 594 597
Liquid density at 25°C kg/m³ 1184 1311
Density of saturated vapour at 25°C kg/m³ 30.9 37.3
Specific heat of liquid at 25°C kJ/kg°C 1.45 1.00
Specific heat of vapour at 1 atm and 25°C kJ/kg°C 0.863 0.606
Vapour pressure at 25°C kPa 707(1) 643
psia 102.6(1) 93.3
Latent heat of vaporisation at boiling point kJ/kg 218 165
Ozone Depletion Potential ODP 0 1
Flammability limit in air (1 atm) vol% None None
Inhalation exposure (8 hr day and 40 hr week) ppm 1000 1000

(1) Bubble point