Lower Water Use Than Cooling Towers
Water is used mainly during high ambient conditions instead of continuous evaporative operation.
Adiabatic Cooler
Adiabatic Cooler
Thermocore adiabatic coolers are designed for HVAC systems, data centers, industrial process cooling, closed-loop glycol systems, free cooling applications and manufacturing facilities where hot-weather performance, low water consumption and process fluid protection are important.
An adiabatic cooler combines dry finned coil cooling with controlled air pre-cooling. During normal conditions, the unit operates like a dry cooler. During high ambient conditions, the adiabatic section reduces the air temperature before it reaches the coil, improving heat rejection while using far less water than a conventional cooling tower.
Product Overview
Adiabatic Cooler Overview
An adiabatic cooler is a closed-loop heat rejection system that combines dry coil cooling with evaporative air pre-cooling. Process fluid, water or glycol flows inside finned tube coils and does not directly contact outside air or spray water. Ambient air passes through or across an adiabatic pre-cooling section before reaching the coil when hot-weather assistance is required.
This product is suitable for projects that need better hot-climate performance than a dry cooler, lower water consumption than a cooling tower, and better fluid protection than open evaporative cooling systems.
Cooling TypeDry cooling + adiabatic air pre-cooling
Fluid LoopClosed-loop water or glycol
Heat Exchange CoreFinned coil + fans + adiabatic media
Water UseIntermittent and lower than cooling tower
Main BenefitWater saving with hot-weather performance
Working Principle
How Does an Adiabatic Cooler Work?
The system usually operates in dry mode first. Hot fluid flows inside the finned tube coil while fans move ambient air across the coil. When dry cooling is not enough, the adiabatic pre-cooling section activates and reduces the air temperature before the air reaches the coil.
1
Hot fluid enters the closed coilWater, glycol or process fluid remains inside the finned tube coil circuit.
2
Fans move air through the unitAmbient air is drawn or pushed across the heat exchange section.
3
Dry cooling handles normal operationHeat transfers from fluid to tube, fins and air without using water in mild conditions.
4
Adiabatic mode activates in hot conditionsWater wets the pre-cooling media and evaporation lowers the air temperature entering the coil.
5
Cooled fluid returns to the systemThe fluid stays protected in the closed loop and returns to the process or chiller system.
Adiabatic Cooling Design
Why Choose an Adiabatic Cooler?
Adiabatic coolers are selected when dry cooling alone cannot maintain the required outlet temperature during hot weather, but the project still needs lower water consumption, closed-loop fluid protection and reduced cooling tower maintenance.
Better Hot-Weather Performance Than Dry Coolers
Adiabatic air pre-cooling lowers the air temperature entering the coil and improves heat rejection capacity.
Closed-Loop Fluid Protection
The process fluid remains inside the coil and is not exposed to outdoor air or open spray water.
Extended Free Cooling Hours
Adiabatic assistance can extend free cooling operation in data center and HVAC systems.
Reduced Plume Risk
Compared with continuous evaporative cooling towers, adiabatic operation can reduce visible plume in many conditions.
Flexible Control Strategy
The unit can operate in dry mode, adiabatic assist mode or staged fan control mode according to system demand.
Applications
Applications of Adiabatic Coolers
Adiabatic coolers are used where customers need water-saving heat rejection with better peak-temperature performance than standard dry cooling. They are suitable for HVAC, industrial process cooling, data centers and closed-loop utility cooling systems.
Compressor
Data Center
HVAC
Industrial Process
Industrial Refrigeration
Pharmaceutical
Plastic Processing
Power Plant
Adiabatic Coolers Application Image Placeholder
Comparison
Adiabatic Cooler vs Dry Cooler
Adiabatic coolers and dry coolers both protect the process fluid inside a closed coil. The main difference is that an adiabatic cooler can reduce the entering air temperature during hot conditions, while a dry cooler relies on ambient air only.
| Item | Adiabatic Cooler | Dry Cooler |
|---|---|---|
| Cooling Method | Dry coil cooling with adiabatic air pre-cooling when needed | Dry sensible air cooling only |
| Water Use | Intermittent water use during adiabatic operation | No water use in standard dry operation |
| Hot-Weather Performance | Better than dry cooler under high ambient conditions | Limited by dry bulb temperature |
| Maintenance | Coils, fans, adiabatic media, water distribution and controls | Coils, fans, controls and fluid loop |
| Best For | Projects needing water saving and better peak ambient performance | Projects where water use should be avoided completely |
| Selection Logic | Choose when dry cooling alone is not enough in hot weather | Choose when outlet temperature target is achievable by dry cooling |
System Comparison
Adiabatic Cooler vs Cooling Tower vs Closed Circuit Cooling Tower
These systems all reject heat, but they use water differently. An adiabatic cooler uses water to pre-cool air only when needed, a cooling tower exposes circulating water directly to air, and a closed circuit cooling tower uses spray water over a closed coil.
| Item | Adiabatic Cooler | Open Cooling Tower | Closed Circuit Cooling Tower |
|---|---|---|---|
| Fluid Protection | Process fluid stays inside dry finned coil | Circulating water is exposed to air | Process fluid stays inside coil |
| Water Use | Intermittent, usually lower annual use | Continuous make-up water required | Spray water loop required during evaporative operation |
| Cooling Limit | Between dry bulb and wet bulb depending on adiabatic effectiveness | Limited by wet bulb temperature | Limited by wet bulb and coil heat transfer |
| Water Treatment | Required for adiabatic water section | Required for open circulating water | Required for spray water loop |
| Best For | Water-saving closed-loop cooling with peak ambient support | Lowest practical evaporative water temperature | Closed-loop fluid protection with evaporative performance |
Technical Selection
Technical Selection Guide
Selecting an adiabatic cooler requires fluid data, ambient air conditions, water quality and operating strategy. A professional selection should consider heat load, fluid type, glycol concentration, dry bulb, wet bulb, annual operating hours, water availability, fan control and desired dry/adiabatic operating sequence.
| Parameter | Why It Matters |
|---|---|
| Heat Rejection Capacity | Determines cooler size and required heat transfer capability. |
| Fluid Type | Water, glycol or process fluid affects heat transfer and pressure drop. |
| Glycol Concentration | Affects viscosity, freezing point, coil sizing and pump power. |
| Fluid Flow Rate | Influences coil circuiting, pressure drop and heat transfer. |
| Inlet / Outlet Fluid Temperature | Defines the required cooling duty and approach target. |
| Design Dry Bulb Temperature | Defines peak dry air cooling condition. |
| Design Wet Bulb Temperature | Helps evaluate adiabatic pre-cooling effectiveness. |
| Water Quality | Affects media life, scaling risk and water treatment requirements. |
| Operating Hours | Determines expected annual water use and adiabatic system duty. |
| Noise Requirement | Affects fan selection, fan speed and control strategy. |
| Control Strategy | Determines dry mode, adiabatic mode, fan staging and water activation logic. |
Key Components
Key Components of an Adiabatic Cooler
Performance depends on the finned coils, adiabatic media, water distribution system, fans, controls, casing, frame and airflow path. Each component should support stable dry operation, controlled adiabatic assistance and practical maintenance.
Finned Tube Coils
The closed heat exchange core where process fluid rejects heat to air.
Adiabatic Media
Pre-cools the incoming air through controlled water evaporation.
Water Distribution System
Supplies water evenly to the adiabatic media or pre-cooling section.
Axial Fan
Moves air through the pre-cooling and coil sections.
Fluid Headers and Connections
Distributes fluid into coil circuits and collect cooled fluid from the unit.
Casing and Frame
Support outdoor installation, airflow path and component protection.
Material Options
Material Options
Material selection affects corrosion resistance, heat transfer, water-side durability, service life and maintenance cost. The best configuration depends on fluid type, water quality, ambient environment, coastal exposure, industrial pollution and budget.
Coil Materials
Coil material should match heat transfer requirements, fluid compatibility and corrosion environment.
Copper tube
Aluminum fin
Stainless steel tube
Epoxy-coated fins
Adiabatic Media and Water Parts
Water-side parts should resist scaling, fouling and mineral deposits under local water conditions.
Adiabatic pads
Water distribution
Drain system
Strainers
Casing, Fan and Electrical Options
Fan, casing and control selections affect airflow, energy consumption, sound level and outdoor durability.
Galvanized steel
Aluzinc steel
EC fan
Low-noise option
Water Management
Adiabatic Water Management
A good adiabatic cooler page should explain water use clearly. Adiabatic coolers reduce water consumption compared with cooling towers, but they still require proper water management because the pre-cooling section uses evaporation during hot conditions.
Intermittent Water Operation
Water is only used when the control system activates adiabatic pre-cooling based on ambient or fluid temperature.
Dry mode first
Water assist only when needed
Water Quality Control
Water quality affects scaling, deposits, biological growth and adiabatic media service life.
Filtration
Bleed / flush logic
Media protection
Winter and Drainage Planning
Cold climate projects should consider drain-down, freeze protection, valve location and seasonal operation mode.
Drain design
Freeze protection
Seasonal controls
Maintenance
Maintenance and Operation Considerations
An adiabatic cooler has lower water system exposure than a cooling tower, but it requires more maintenance than a dry-only cooler. Coil cleanliness, media condition, water distribution and control logic should be checked regularly.
Coil and Airside Cleaning
Finned coils and air inlet areas should be kept clean to maintain airflow and heat transfer efficiency.
- Inspect fin surface
- Remove dust and debris
- Avoid fin damage during cleaning
Adiabatic Media Inspection
Media, pads or wetting sections should be inspected for scaling, clogging, uneven wetting and mineral deposits.
- Check media condition
- Verify water distribution
- Clean strainers and valves
Fluid Loop and Controls
Closed-loop fluid and controls should be monitored to maintain stable outlet temperature and freeze protection.
- Check glycol concentration
- Monitor inhibitors
- Verify dry / adiabatic control sequence
Advantages
Performance Advantages
Adiabatic coolers are selected when customers need water-saving heat rejection with better hot-weather performance than dry cooling alone.
Lower Annual Water Use
Water is used only during adiabatic assist periods instead of continuous evaporation.
Closed Fluid Loop
Process fluid remains inside the coil and is not exposed to outside air.
Improved Peak Performance
Adiabatic pre-cooling improves capacity during high dry bulb conditions.
Free Cooling Support
Can extend free cooling operation for HVAC and data center systems.
Reduced Cooling Tower Burden
Lower drift, blowdown and open-water exposure than many cooling tower systems.
Flexible Operation Modes
Dry mode, adiabatic mode and fan speed control can be staged by system demand.
Suitable for Water-Sensitive Sites
Useful where water cost, water scarcity or discharge control is a project concern.
Custom Engineering Support
Coil, media, fan, control and material options can be configured for project needs.
Custom Engineering
Custom Engineering Options
Thermocore can customize adiabatic coolers according to heat rejection capacity, fluid type, glycol concentration, coil material, adiabatic media, fan configuration, water management, control strategy, casing material, noise requirement, installation layout and export shipping requirements.
Thermal Customization
For projects with special heat load, fluid temperature, approach or dry/wet bulb requirements.
Heat rejection
Flow rate
Approach temperature
Dry / wet bulb design
Adiabatic System Customization
For water saving, media selection, water distribution, flushing, drainage and water quality requirements.
Adiabatic pads
Water distribution
Flush control
Drain design
Fan, Coil and Control Customization
For low noise, energy saving, corrosion resistance, BMS integration and special voltage requirements.
EC fans
VFD control
Coated coils
BMS signal
Not Sure Whether Adiabatic Cooler Is Right for Your Project?
Send your heat rejection capacity, fluid type, glycol concentration, flow rate, inlet and outlet temperature, design dry bulb and wet bulb temperature, water quality and operating schedule. Our engineering team will compare adiabatic cooler, dry cooler, closed circuit cooling tower and open cooling tower options for your project.
Heat rejection
Fluid / glycol
Dry & wet bulb
Water quality
Operating hours
FAQ
Adiabatic Cooler FAQ
These FAQs are written for HVAC engineers, data center teams, industrial buyers and contractors who need to understand adiabatic cooler selection, dry/adiabatic operation, water management, controls, maintenance and customization.
What is an adiabatic cooler?
An adiabatic cooler is a closed-loop air-cooled heat rejection unit that combines dry cooling with adiabatic air pre-cooling. Process fluid, water or glycol flows inside finned tube coils, while ambient air passes across the coil surface. During hot ambient conditions, an adiabatic pre-cooling system wets pads, media or a controlled air pre-cooling section before the air reaches the coil. This reduces the entering air temperature and improves heat rejection while using much less water than a conventional open cooling tower.
How does an adiabatic cooler work?
Hot fluid enters the closed finned tube coil. In normal conditions, fans move ambient air across the coil for dry sensible heat rejection. When ambient temperature rises or outlet fluid temperature cannot be maintained in dry mode, the adiabatic system activates. Water is applied to pre-cooling media or an air-side wetting section, and evaporation lowers the air temperature before it reaches the coil. The cooler can then reject more heat while the process fluid remains isolated inside the coil.
Why choose an adiabatic cooler?
An adiabatic cooler is selected when a project needs lower outlet fluid temperatures than a standard dry cooler can provide in hot weather, but the customer still wants lower water consumption and better fluid protection than an open cooling tower. It is useful for HVAC, industrial process cooling, data centers, free cooling loops and water-sensitive projects that require a balance between energy efficiency, water saving and thermal performance.
What is the difference between an adiabatic cooler and a dry cooler?
A standard dry cooler rejects heat using ambient air only, so its performance is limited by dry bulb temperature. An adiabatic cooler adds a water-assisted air pre-cooling stage that lowers the air temperature entering the coil during hot conditions. This allows the adiabatic cooler to achieve lower fluid outlet temperatures or smaller equipment size than a dry-only cooler in many climates, but it requires water supply, water management and additional maintenance for the adiabatic section.
What is the difference between an adiabatic cooler and a cooling tower?
A cooling tower exposes circulating water directly to air and uses continuous evaporative cooling. An adiabatic cooler keeps the process fluid inside a closed coil and only uses water to pre-cool the air when needed. Cooling towers can often reach lower water temperatures closer to wet bulb temperature, but they require more water treatment and make-up water. Adiabatic coolers usually consume less water and provide better process fluid isolation.
What is the difference between an adiabatic cooler and a closed circuit cooling tower?
Both can protect the process fluid inside a coil. A closed circuit cooling tower uses spray water over the coil for evaporative heat transfer, while an adiabatic cooler mainly cools the incoming air before it reaches a dry finned coil. The adiabatic cooler usually has lower water consumption than continuous spray coil systems, but closed circuit cooling towers may provide stronger evaporative performance when very low fluid temperatures are required.
What information is needed for adiabatic cooler selection?
Important selection data includes heat rejection capacity, fluid type, glycol concentration if applicable, fluid flow rate, inlet fluid temperature, required outlet fluid temperature, design dry bulb temperature, design wet bulb temperature, project location, altitude, operating hours, water availability, noise requirement, power supply and material preference.
Does an adiabatic cooler need water treatment?
Yes, but the water treatment requirement is usually different from an open cooling tower. The process fluid is closed inside the coil, but the adiabatic pre-cooling water still needs water quality management to reduce scaling, biological growth, mineral deposits and media fouling. The required treatment depends on water quality, operating hours, bleed strategy and adiabatic system design.
What materials are commonly used?
Common material options include copper tube aluminum fin coils, stainless steel tubes, epoxy-coated fins, galvanized steel casing, Aluzinc steel casing, stainless steel casing, adiabatic pre-cooling media, water distribution piping, axial fans, EC fans and control panels. Material selection should consider water quality, ambient environment, coastal exposure, industrial pollution and required service life.
What should I send to get a quotation?
To receive an accurate quotation, send the heat rejection capacity, fluid type, glycol concentration, flow rate, inlet and outlet fluid temperatures, design dry bulb temperature, design wet bulb temperature, project location, altitude, water quality, operating schedule, power supply, installation space, noise requirement, material preference and any control or customization requirements.
Start Your Project
Need an Adiabatic Cooler for Your Cooling Project?
Send us your heat rejection capacity, fluid type, glycol concentration, flow rate, inlet and outlet fluid temperature, design dry bulb and wet bulb temperature, project location, water quality and noise requirement. Our engineering team will help you select a suitable adiabatic cooler configuration.