Makawi R404A Refrigerant
Makawi R404A Refrigerant
Makawi R404A is a near-azeotropic blend of the hydrofluorocarbons R-125, R-143a and R-134a. It is formulated to match the properties of R-502 closely and does not harm the ozone layer. It is one of the most widely used refrigerants in the medium and low temperature applications of commercial refrigeration.
Properties and performance
Its ASHRAE safety group is A1 and its ozone depletion potential is zero. Thanks to its near-azeotropic behaviour, temperature glide is negligible. It gives stable capacity at low evaporating temperatures, which is why it is preferred in freezer and cold room applications. Most compressor and system manufacturers approve R404A for use in their new equipment.
Lubricant
It is not miscible with the traditional oils used in R-502 systems. In a retrofit the existing oil must be changed to POE and the old oil brought to 5% of the total charge or below. If this is not done, oil return is compromised and the compressor can run dry.
Charging
As a blend it is charged in the liquid phase. Where it must be fed as vapour, a valve that flashes the liquid is fitted to the charging line. Field experience shows that composition shift caused by leakage is not a practical problem with R404A: repairing the leak and topping up the charge is sufficient.
Retrofitting R-502 systems
R404A can be used as a retrofit refrigerant in many existing R-502 systems; its physical and thermodynamic properties behave close to those of R-502. It is, however, not intended as a drop-in: an oil change is required, and because working pressures are higher than with R-502 the pressure safety devices must be reviewed.
Technical data
| Composition | HFC-143a (CAS 420-46-2) + HFC-125 (CAS 354-33-6) + HFC-134a (CAS 811-97-2) |
| Average molecular weight | 97.6 g/mol |
| Normal boiling point | −46.4 °C (−51.5 °F) |
| Critical temperature | 72.0 °C (161.6 °F) |
| ASHRAE safety group | A1 (low toxicity, non-flammable) |
| Ozone depletion potential (ODP) | 0 |
| Global warming potential (GWP) | 3,200 |
| Lubricant | POE (polyol ester) |
| Packaging | 10.9 kg (24 lb) single-use steel cylinder |
Where it is used
Supermarket display and storage cabinets, cold stores and cold rooms, ice machines, transport refrigeration, process cooling, and the retrofit of existing R-502 systems.
Note: R404A has a high global warming potential (GWP 3,200). For newly built systems it may be worth evaluating lower-GWP alternatives, which can be an advantage in the long run both for regulatory compliance and for cost; ask us for help with the selection.
Storage and safety
- Store cylinders upright in a cool, ventilated area, away from direct sunlight and temperatures above 50 °C.
- Liquid refrigerant causes frostbite on contact with skin — wear gloves and eye protection.
- The vapour is heavier than air and displaces oxygen in confined spaces, creating a risk of asphyxiation. Ventilation is essential indoors.
- Never vent to the atmosphere: recover the refrigerant with a recovery unit during service and decommissioning.
- Read the product safety data sheet (SDS) before use.
Contact the Lapin team for cylinder quantities, lead times and current pricing.