Dorin CO2 — the Italian transcritical specialist
By DigiEntropy Engineering · 2026-03-08 · 5 min read
Officine Mario Dorin (Florence, Italy) builds reciprocating compressors that almost exclusively target transcritical and subcritical R744 applications. The CD-series is the EU reference for compact CO2 commercial refrigeration. A focused brand worth knowing.
About this post — Authored by an AI assistant using DigiEntropy's polynomial corpus, the universal compressor predictor, and the project's chart-generation tooling. Charts are produced by Python scripts that read the same database the live site queries; tables and formulas are pulled from the same engineering modules. Findings reflect the project's current dataset and methodology — send corrections or deeper questions to admin@digientropy.com.
Officine Mario Dorin (Florence, Italy) has spent the last 15 years narrowing their product line: where competitors have broadened across refrigerants, Dorin has gone deeper on one — R744 / transcritical CO2. The result is a brand that does one thing exceptionally well, and is widely spec'd when that one thing is what you need.
The CD-series (transcritical) and CC-series (subcritical) are Dorin's main DigiEntropy presence. Compact reciprocating CO2 compressors covering 3 kW to 80 kW per unit — exactly the band where R744 commercial refrigeration packs live.
15 years - narrowing to one refrigerant - R744 / transcritical CO2
Officine Mario Dorin (Florence, Italy) has spent the last 15 years narrowing their product line: where competitors have broadened across refrigerants, Dorin has gone deeper on one — R744 / transcritical CO2.
80 kW - top of the per-unit range - from 3 kW
Compact reciprocating CO2 compressors covering 3 kW to 80 kW per unit — exactly the band where R744 commercial refrigeration packs live.
130 bar - CD-series discharge rating - suction rating: 50 bar
Transcritical-rated, semi-hermetic reciprocating. Capacity range: 5-50 kW per compressor. Discharge rating: 130 bar. Suction rating: 50 bar.
4949 - polynomial rows decoded - from a 17 MB pickle file
The decoded catalog: 4949 polynomial rows + 515 model-asset entries + 422 model tech-spec entries.
35 - distinct compressor variants - R744 + legacy refrigerants
Covers 35 distinct compressor variants across R744 + legacy refrigerants. Each model carries qualified-refrigerant + envelope-limit data alongside the polynomials.
Why a specialist brand matters
Most refrigeration brands cover the full refrigerant landscape — HFCs, HFOs, naturals — across many compressor families. The advantage: one supplier relationship for everything. The disadvantage: tradeoffs in any individual application.
Dorin's transcritical-CO2 specialisation gets you:
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Optimised for high pressure - 100+ bar discharge
Cylinder + valve + crankcase engineering tuned for CO2's pressure regime, not adapted from HFC heritage.
Compact form factor
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