An outdoor air handling unit (AHU) is a ventilation unit designed to be installed outside a building—typically on the roof or against an exterior wall. It is fully weatherproof, insulated, and built to withstand varying temperatures, humidity, wind, and mechanical stress. Outdoor AHUs have become increasingly common, especially in industrial settings and large buildings where indoor machine room space is limited or where high ventilation capacity is required.
What Does an Outdoor AHU Mean in Practice?
An outdoor AHU differs from an indoor unit in terms of its structure and level of protection. Key features include:
- Fully weather-resistant casing (corrosion-resistant materials, tight joints)
- Thermal and condensation insulation to prevent cold bridges and freezing
- Insulated service doors and compartments to protect components
- Robust base/frame to safely transfer loads to the roof or ground foundation
- Design for northern climates: frost protection, defrost solutions, and condensate management
- Depending on the application, the unit may include a counterflow heat exchanger, coil heat exchanger, or plate heat exchanger.
When is an Outdoor AHU the Best Choice?
Outdoor AHUs are used whenever indoor space is insufficient or when placing the unit outside provides clear technical or economic advantages.
1. When there is no machine room or it is too small
In many industrial and commercial buildings, machine rooms are limited, or expanding them would be costly. An outdoor AHU solves space challenges without major structural modifications.
2. Industrial halls and production facilities
For projects with large airflows, units are physically large. Outdoor installation:
- Frees up indoor space for production
- Reduces noise impact
- Facilitates maintenance and spare parts replacement
- This is one of the most common use cases.
3. When modernizing a building’s ventilation
- An outdoor unit is often the easiest and fastest way to renovate ventilation without internal structural changes.
4. When high energy efficiency (heat recovery) is required
Modern outdoor AHUs can be equipped with:
- Counterflow heat exchangers
- Efficient EC fans
- Precise automation
This provides significant savings, especially in industrial applications with large airflows.
5. Applications with special requirements
Outdoor AHUs are particularly suitable for:
- Food industry
- Chemical and process industries
- ATEX areas (optional)
- Cleanrooms
- Warehouses and logistics centers
- The unit can be precisely customized to meet the application’s requirements.
Advantages of Outdoor Installation
- No need for a separate machine room
- Frees up usable indoor space
- Easy to install and maintain
- Weather-resistant design lasts for decades
- Supports higher airflow and capacities
- Cost-effective solution for renovation projects
Summary
An outdoor AHU is an excellent solution when there is insufficient indoor space, when large airflows are required, or when a technically efficient and easy-to-maintain ventilation solution is desired. Its weatherproof design and modern heat recovery make it particularly suitable for industrial facilities and large buildings.
ClimaPro – Outdoor AHUs – Why Choose Us?
✔ Domestic design and manufacturing
We build AHUs in Finland, tailored for Finnish conditions.
✔ Customized sizing
Each unit is designed for the specific customer, ensuring optimal energy efficiency, usability, and maintainability.
✔ Robust and weather-resistant design
We use high-quality materials and thermal insulation to ensure flawless operation year-round.
✔ Direct support for designers and contractors
We assist throughout the project: sizing, technical support, modernization, and lifecycle planning.