R-404A is an almost azeotropic mixture of HFC refrigerants, with zero ozone layer depletion, used in new refrigeration equipment at mid-range and low temperatures. It is also an indirect replacement (retrofit), in equipment that previously operated with R-502 and its HCFC replacements such as R-408A, DI-44, and HP80.
It is mainly used in new installations with mid-range and low refrigeration temperatures. The theoretical cooling capacity is 5% lower than R-502 at evaporation temperatures of -40ºC. The coefficient of performance (COP) is between 5 and 8% lower than R-502. As superheating increases, R-404A’s COP might become higher than that of R-502. In the case of R-502 retrofits and its HCFC replacements (R-408A, DI-44), 95% of the original mineral oil or alkylbenzene must be replaced by a polyolester oil, the dryer filter and expansion valve changed, rubber O-rings replaced with plastic ones and, occasionally, the size of the condenser must be increased. When it is used as a retrofit for R-22, the safety valves also need to be changed along with any other elements calibrated to R-22 pressures.
· Water coolers.
· Cold stores.
· Refrigerated display cabinets.
· Ice cream/ice machines.
· Ice rinks.
· Cold chambers.
· Refrigerated transport.
· Cold drinks dispenser.
· Freezing tunnels.
· Fishing boats.
- Medium temperatures
- Low Temperatures
- new Installations
· Dos not damage the ozone layer, ODP = 0.
· Only compatible with POE synthetic oils.
· Equipment can be refilled in the case of leakage.
· Lower discharge temperatures than R-22, which extends the life of the compressor.
· Slightly lower cooling capacity and energy efficiency than R-502.
· Higher cooling capacity and similar energy efficiency to that of R-22.
· Global warming potential (GWP) = 3922
· Boiling point at 1.013 bar (ºC): -46.45
· Temperature slip or glide (ºC): 0.7
· Saturated vapour density at 25ºC (kg/m3): 63.28
· UN nº: 3337
· Safety classification: A1. Low toxicity and nonflammable.
· Always load in its liquid phase.
- Synthetic POE oils
With the aim of working with just one refrigerant, R404A has been used to work in equipment with low and mid-range evaporation temperatures and also in air conditioning. On the other hand the cooling capacities of R-404A and R-507 are much higher in mid-range refrigeration temperatures compared to R-134a. Nevertheless, these advantages are counterbalanced by a significant decrease in the coefficient of performance (COP) of R-404A and R-507 compared to R-134a. The greater the evaporation temperature, the lower the COP. The vapour pressure is slightly lower than that of R-507. The cooling capacity and the COP are both slightly lower compared to R-507 and very much lower compared to R-442A (RS50).