Ammonia R717 is a natural refrigerant gas, with multiple applications in industrial refrigeration, especially in R744 cascade systems or in secondary fluid systems, such as glycol water.

Its main characteristics are:

  • High refrigerating power
  • GWP – Global Warming Potential = 0
  • ODP – Ozone Depletion Potential =0
  • Availability at a constant price

Particular care must always be taken when handling and storing this refrigerant because it is a toxic gas (regulated by Royal Decree 147/27), flammable in certain concentrations and incompatible with copper and its alloys. Its good solubility in water prevents the formation of ice in the system, but in high percentages humidity can cause corrosion or mechanical problems due to the formation of sludge.

CompositionPurityImpurities (ppmv)Supply modeCapacity (l)Contents (kg)
NH3≥ 99.5 %0H2O ≤ 3000
O ≤ 50       
Oils ≤ 10
Large cylinder250 l125 kg
Steel cylinder40 l20 kg
Maximum degree of filling: 0.53kg/l                                                            
Valve connection: Group III – UNI 4407

Chemical and physical properties
Physical state:Liquefied gas
Molecular weight:17 g/mol
Melting point:-77.7 °C
Boiling point (at 1,013 bar):-33 °C
Critical temperature:-132.4 °C
Critical pressure:114.8 bar
Relative density, gas (*):0.6 (air=1)
Relative density, liquid:0.7 (water=1)
Absolute density (*):1.161 g/l
Appearance/colour:Colourless gas
Auto-ignition temperature:630°C
Flammability limit in air:15 to 30
Exposure limit value (TLV):25
Safety classification (ASHRAE 34)B2
(*) at 1.013 bar and 21.1 °C