| 1/00 | Compression machines, plant or systems with non-reversible cycle (F25B 3/00, F25B 5/00, F25B 6/00, F25B 7/00, F25B 9/00 take precedence) |
| 1/02 | Compression machines, plant or systems with non-reversible cycle (F25B 3/00, F25B 5/00, F25B 6/00, F25B 7/00, F25B 9/00 take precedence) with compressor of reciprocating-piston type (F25B 1/1 takes precedence) |
| 1/04 | Compression machines, plant or systems with non-reversible cycle (F25B 3/00, F25B 5/00, F25B 6/00, F25B 7/00, F25B 9/00 take precedence) with compressor of rotary type (F25B 1/1 takes precedence) |
| 1/047 | Compression machines, plant or systems with non-reversible cycle (F25B 3/00, F25B 5/00, F25B 6/00, F25B 7/00, F25B 9/00 take precedence) with compressor of rotary type (F25B 1/1 takes precedence) of screw type |
| 1/053 | Compression machines, plant or systems with non-reversible cycle (F25B 3/00, F25B 5/00, F25B 6/00, F25B 7/00, F25B 9/00 take precedence) with compressor of rotary type (F25B 1/1 takes precedence) of turbine type |
| 1/06 | Compression machines, plant or systems with non-reversible cycle (F25B 3/00, F25B 5/00, F25B 6/00, F25B 7/00, F25B 9/00 take precedence) with compressor of jet type, e.g. using liquid under pressure (F25B 1/1 takes precedence) |
| 1/08 | Compression machines, plant or systems with non-reversible cycle (F25B 3/00, F25B 5/00, F25B 6/00, F25B 7/00, F25B 9/00 take precedence) with compressor of jet type, e.g. using liquid under pressure (F25B 1/1 takes precedence) using vapour under pressure |
| 1/10 | Compression machines, plant or systems with non-reversible cycle (F25B 3/00, F25B 5/00, F25B 6/00, F25B 7/00, F25B 9/00 take precedence) with multi-stage compression (with cascade operation F25B 7/00) |
| 3/00 | Self-contained rotary compression machines, i.e. with compressor, condenser, and evaporator rotating as a single unit |
| 5/00 | Compression machines, plant, or systems, with several evaporator circuits, e.g. for varying refrigerating capacity (with cascade operation F25B 7/00) |
| 5/02 | Compression machines, plant, or systems, with several evaporator circuits, e.g. for varying refrigerating capacity (with cascade operation F25B 7/00) arranged in parallel |
| 5/04 | Compression machines, plant, or systems, with several evaporator circuits, e.g. for varying refrigerating capacity (with cascade operation F25B 7/00) arranged in series |
| 6/00 | Compression machines, plant, or systems, with several condenser circuits |
| 6/02 | Compression machines, plant, or systems, with several condenser circuits arranged in parallel |
| 6/04 | Compression machines, plant, or systems, with several condenser circuits arranged in series |
| 7/00 | Compression machines, plant, or systems, with cascade operation, i.e. with two or more circuits, the heat from the condenser of one circuit being absorbed by the evaporator of the next circuit (F25B 9/00 takes precedence) |
| 9/00 | Compression machines, plant, or systems, in which the refrigerant is air or other gas of low boiling point |
| 9/02 | Compression machines, plant, or systems, in which the refrigerant is air or other gas of low boiling point using Joule-Thompson effect; using vortex effect |
| 9/04 | Compression machines, plant, or systems, in which the refrigerant is air or other gas of low boiling point using Joule-Thompson effect; using vortex effect using vortex effect |
| 9/06 | Compression machines, plant, or systems, in which the refrigerant is air or other gas of low boiling point using expanders (F25B 9/1 takes precedence) |