Background
Flensburger Brauerei operates two interconnected fermentation cellars (known as "Gelber Raum" and "Roter Raum") with a combined volume of approximately 11,000 m³ (7,500 m³ of air space due to tank volumes).
The facility faced severe humidity problems with room temperatures of 10-15°C and tank temperatures of 5°C. Before installation, humidity levels varied between 60-95% RH, with frequent peaks exceeding 75% RH depending on external conditions and cleaning schedules.
As a brewery with high quality standards, Flensburger wanted to lead the way in production environment climate control. The objective was to create optimal conditions for the yeast process while ensuring long-term structural integrity through proactive humidity control.
What problems did Airwatergreen's dehumidifiers solve?
The main issue was uncontrolled humidity, which caused condensation primarily on cold tanks. The NEXT 400 unit was positioned outside the yeast halls and connected via ducted air circulation to both rooms, supplying dry air with a maximum of 40% RH. This configuration was necessary because the machine could not physically fit inside the rooms (due to narrow 90 cm doorways).
With the NEXT 400 in operation since May 2025, the climate has been dramatically stabilized. The indoor humidity is now consistently maintained at 60±5% RH, with the system extracting between 5–13 kg of water per hour. Before-and-after data demonstrates a clear transformation: fluctuations of 60–95% RH prior to installation have been replaced by stable control at 60±5% RH.
Operational benefits
Since the installation in May 2025, Flensburger Brauerei has achieved the following concrete improvements:
Humidity control
- Stable conditions: Consistent 60±5% RH (down from 60-95% RH fluctuations)
- Room 1 performance: 70±5% RH at 14°C (sensor 1-controlled)
- Room 2 performance: 60±5% RH at 15°C (sensor 2-monitored)
- Elimination of condensation on cold fermentation tanks
Maintenance and cost reduction
- Mold prevention: Zero mold formation since installation
- Reduced building preservation maintenance
- Reduced cleaning frequency required for mold removal
- Lower maintenance on cooling and fermentation equipment
Why the Airwatergreen solution made a difference
The brewing industry places unique demands on humidity control. Traditional dehumidifiers struggled with Flensburger's specific challenges: low temperatures (10–15°C), limited installation space, and the need to manage two separate areas simultaneously.
The benefits of CVP technology in brewery environments
Airwatergreen's patented CVP technology operates efficiently in the challenging 10–15°C environment typical of fermentation cellars, where conventional dehumidifiers struggle or fail entirely. Without effective dehumidification, breweries risk product quality issues from mold contamination, increased operating costs from constant cleaning and repainting, and potential equipment corrosion from persistent moisture.
Flexible installation that overcomes practical obstacles
The external placement solution of the NEXT 400 overcame the physical installation challenge (narrow doorways) while still delivering efficient coverage of two rooms through optimized air distribution ductwork. Air ducts were routed through existing windows (by removing the glass panes), 32A power was connected from the inside, and drainage was straightforwardly managed during the test period.
Long-term value creation
For Flensburger Brauerei, the solution meant not only the elimination of an acute problem but a fundamental improvement in production conditions. Stable climatic conditions ensure optimal yeast quality, while protecting the building from moisture damage and providing staff with a healthier environment free from mold impact.
The system is monitored via the cloud-based AWG Climate Control System, providing real-time data on humidity levels, water extraction, and energy consumption. This makes it a reliable and efficient choice for breweries needing to maintain strict climate control for yeast quality while reducing maintenance costs and ensuring building longevity.