Refrigerant Compressed Air Dryer
Sub-Zero Refrigeration Dryers
Revolutionary Regenerative Refrigerated Dryers
Why choose a sub zero refrigeration dryer?
The revolutionary CMT dryer is the only regenerative refrigerant dryer available in the compressed air market today. It combines the sub zero pressure dew point (PDP) of a typical regenerative desiccant dryer, with the low operating and energy costs of a refrigerant dryer, to provide an extremely low total cost of ownership (TCO). Sub zero air dryers take clean, dry air to new levels of cost-efficiency across a broad spectrum of operating conditions.
Optimised for Class 3 air quality
Many applications require very dry, high-quality air with sub zero dew points. CompAir’s desiccant dryers are the best option for the most stringent requirements – ISO Class 1-2 with a pressure dew point (PDP) as low as -70°C (-94°F). However, ISO Class 3 air, with a PDP of -20°C (-4°F), is sufficient for a large portion of the market. For applications that only require Class 3 air, we've expanded our family of high quality air dryers with our CMT dryers. They combine the ease of maintenance and operation of a refrigerated dryer with the sub zero pressure dew points typically associated with a desiccant dryer. Please download our white paper at the bottom of the dryers homepage to learn more about the ISO classes and how the apply to compressed air. Please contact us directly to get further information on this topic.
Features
Pre-Cooling
Air enters the dryer through the pre-cooler/re-heater
Regeneration
Leaving the pre-cooler/ re-heater, the air enters the first heat exchanger for regeneration
Drying
With only 15% of the of the moisture remaining, the air now enters the sub zero dryer heat exchanger where it is cooled and dried to -20°C (-4°F) PDP.
Reheating
The air dried to -20°C (-4°F) PDP is reheated before exiting the dryer in two steps.
Please download the brochure under the downloads tab to learn more about these dryers
Both Refrigerant Compressed Air Dryers and Sub-Zero Refrigeration Dryers are used in compressed air systems to remove moisture from compressed air, but they work in slightly different temperature ranges and applications. Here’s a clear comparison:
1️⃣ Refrigerant Compressed Air Dryer
A Refrigerant Compressed Air Dryer is the most common type of air dryer used in industrial compressed air systems.
How it Works
Warm compressed air enters the dryer.
A refrigeration system cools the air to about +2°C to +5°C dew point.
Moisture condenses into water.
Water is separated and drained out.
Key Features
Pressure Dew Point: +2°C to +5°C
Energy efficient
Low maintenance
Suitable for most industrial applications
Common Applications
Manufacturing plants
Automotive workshops
Pneumatic tools
Packaging industries
2️⃣ Sub-Zero Refrigeration Dryer
A Sub-Zero Refrigeration Dryer is a specialized low-temperature refrigeration dryer designed to reach dew points below 0°C.
How it Works
Uses advanced refrigeration cycles to cool compressed air below freezing temperature.
Can achieve dew points around -20°C or lower depending on design.
Key Features
Pressure Dew Point: -10°C to -20°C or lower
Prevents freezing in cold environments
Provides much drier air than standard refrigeration dryers
Common Applications
Cold climate operations
Food processing
Pharmaceutical manufacturing
Instrument air systems
🔎 Main Difference
Feature Refrigerant Dryer Sub-Zero Refrigeration Dryer
Dew Point +2°C to +5°C -10°C to -20°C
Dryness Level Moderate Very Dry
Cost Lower Higher
Applications General industry Critical or cold environments
✅ Simple summary:
Refrigerant Dryer → Standard industrial moisture removal
Sub-Zero Dryer → Extra-dry air with dew point below 0°C
If you want, I can also explain:
Types of compressed air dryers (5 main types)
Refrigerated vs Desiccant dryer differences
How to select the right dryer for an air compressor system.
