Technical Knowledge · NH₃ Refrigerant · Russian Industrial Practice · HFC vs Ammonia · CIS
NH₃ (R-717) has been the dominant refrigerant in Russian industrial refrigeration for over a century and remains so today, despite the wide availability of HFC and HFO synthetic refrigerants that have largely displaced ammonia in Western European commercial refrigeration. The reasons are thermodynamic, economic, and regulatory — and they are unlikely to change in the Russian context within the foreseeable future. This article explains why Russian cold chain operators, fish processing plants, blast freeze facilities, and industrial process cooling installations continue to specify ammonia refrigeration systems, and what this means for compressor selection.
✓ HFC vs Ammonia
✓ Regulatory Landscape
✓ DW / 4MW NH₃ Series
4MW series ammonia refrigeration compressor in service at a large Russian cold chain facility — the 4MW frame is the standard specification for industrial NH₃ systems above 350 kW in Russia, where ammonia’s superior thermodynamic efficiency and zero global warming potential make it the economically and environmentally rational choice for large-scale industrial refrigeration.
The Thermodynamic Case for Ammonia
Ammonia has the highest refrigerating effect per unit mass of any common refrigerant — approximately 1,370 kJ/kg at −15°C evaporating temperature, compared with 163 kJ/kg for R-404A and 218 kJ/kg for R-134a at the same condition. This means that an ammonia refrigeration system circulates roughly 6–8 times less refrigerant by mass than an equivalent HFC system to achieve the same refrigerating capacity, which reduces the size of the heat exchangers, pipework, and compressor relative to the heat exchangers, pipework, and compressor required for HFC service. Smaller refrigerant pipework diameters reduce capital cost and refrigerant inventory.
The COP of an ammonia refrigeration system is consistently 3–10% higher than an equivalent HFC system at the same operating conditions. This COP advantage is most pronounced at low evaporating temperatures — exactly the conditions prevalent in Russian industrial refrigeration applications such as blast freezing (−35°C to −40°C evaporating) and deep-freeze cold storage (−25°C to −30°C evaporating). For a 500 kW refrigeration installation operating 8,000 hours per year with a COP advantage of 5%, the annual energy saving from specifying NH₃ instead of R-404A amounts to approximately 25,000 kWh per year — a significant operating cost reduction over the 25–30 year life of an industrial refrigeration plant.
Ammonia vs HFCs in Russian Industrial Practice

| Factor | NH₃ (R-717) | R-404A (HFC) | R-134a (HFC) |
|---|---|---|---|
| Global Warming Potential | 0 | 3,922 | 1,430 |
| Refrigerating effect (−15°C) | 1,370 kJ/kg | 163 kJ/kg | 218 kJ/kg |
| Relative system COP | Best | 3–10% lower | 3–7% lower |
| Refrigerant purchase cost | Very low | High (10–20x NH₃) | Moderate |
| Flammability | B2L (mildly flammable) | A1 (non-flammable) | A1 (non-flammable) |
| Toxicity | B (toxic above 300 ppm) | A (low toxicity) | A (low toxicity) |
| Leak detectability | Excellent (sharp odour) | Poor (odourless) | Poor (odourless) |
GWP values based on AR4 100-year values. COP comparison at −25°C evaporating / +35°C condensing.
The Russian Regulatory Context
Russia is a signatory to the Montreal Protocol but has not adopted the European F-Gas Regulation that drives HFC phase-down in the EU. The Russian regulatory framework for refrigerants is governed primarily by GOST standards and Rostechnadzor rules for hazardous industrial equipment — and ammonia has been the subject of these regulations for decades, with a well-established compliance framework that Russian industrial operators know and understand. The Kigali Amendment to the Montreal Protocol commits Russia to an HFC phase-down schedule, but the Russian implementation timeline extends further than the EU phase-down, and the regulatory pressure to switch from ammonia — which has a GWP of zero — to HFO alternatives simply does not exist in the Russian context.
The practical result is that Russian industrial refrigeration system designers, installers, and operators have continued to develop their expertise in ammonia systems throughout the period when Western European practice shifted toward HFCs. The engineering knowledge base for ammonia refrigeration design, installation, safety management, and maintenance is deep in Russia. Technicians trained on ammonia systems are available throughout the country. Spare parts for ammonia compressors, condensers, evaporators, and controls are stocked by Russian suppliers. This infrastructure advantage further reinforces ammonia’s dominance: switching to an HFC refrigerant in a Russian industrial setting means sourcing refrigerant from a limited number of suppliers, working with a smaller pool of HFC-experienced engineers, and losing the practical cost advantages of ammonia’s thermodynamic properties.
Applications Where Ammonia Dominates in Russia

Ammonia Safety: Why Toxicity Is Manageable at Industrial Scale
The main objection to ammonia is its toxicity — ammonia is classified as B2L (toxic and mildly flammable) and requires safety measures not needed for HFC refrigerants. However, at industrial scale, this toxicity disadvantage relative to HFCs is significantly smaller than it appears in commercial refrigeration contexts for three reasons:
Why PET Bottle Plants Use Chiller Cooling, Not NH₃ Refrigeration
Injection stretch blow moulding (ISBM) plants producing PET bottles cool the blow moulds and the preform conditioning zone using chilled water circuits at +8°C to +12°C — not ammonia refrigeration at −25°C. The cooling duty in an ISBM plant is modest compared with a cold storage or blast freezing installation — typically 50–200 kW of mould cooling — and the temperature level required (+8°C to +12°C chilled water) is achievable with air-cooled HFC or HFO chillers of 20–200 kW capacity without the safety infrastructure that ammonia refrigeration at industrial scale requires. This is the practical boundary between where ammonia dominates (large-scale refrigeration at low temperatures) and where HFC or HFO chillers are more appropriate (small to medium process cooling at moderately low temperatures). ISBM plants sit firmly in the second category. The ammonia refrigeration compressors described in this series are specified for the cold chain and industrial process cooling installations that supply the food and beverage products that the ISBM industry packages.
FAQ — Ammonia Refrigerant in Russian Industrial Practice
DW and 4MW Series Ammonia Refrigeration Compressors
DW series (55–350 kW) and 4MW series (350–1,600 kW) ammonia reciprocating compressors for single-stage and two-stage compound refrigeration — cold storage, blast freezing, fish processing, brewery, and industrial process cooling. GOST-R certified. Full Russian documentation. Response within 48 hours.