R290 (propane)
Also known as: propane, R-290
Short definitionRefrigeration-grade propane. An efficient natural refrigerant with a GWP of 3; being flammable (A3), it is used with a limited charge in sealed, leak-tight equipment.
R290 is the same substance as bottled propane, only at about 99.5% purity. Its efficiency is 10–15% higher than R404A, its pressures are close to R22 and it works with mineral and POE oil. It has no effect on the ozone layer. Its one serious obstacle is flammability, which is why standards limit the charge per appliance. Charges up to 500 grams are common in hermetic commercial equipment.
In small rooms you meet it in plug-in monoblock units. In large stores the propane chiller stays in the plant room and a secondary circuit carrying glycol or CO₂ goes to the room. As the charge grows, an ATEX-compliant plant room, gas detector and ventilation are needed; these enter the quotation as separate items. Service is done only by technicians trained in flammable refrigerants.