Beutelsbach in the magnificent vicinity of Stuttgart. The monastery is located in the old city center, adorned with timber framing. Among other things, a gym, a community cinema and an event location in the old monastery cellar have been set up. A single ventilation system supplies the rooms with air, using a lot of electricity in the process.
A planning office commissioned by the city turned to the company Pfänder, which mainly automates buildings. “We do not build ventilation or heating systems ourselves, but rather take care of their control system, programming for example when and where ventilation, heating or cooling is required,” says Lukas Pfänder. Many customers come to Lukas and his brother Tobias Pfänder with old ventilation systems that consume too much electricity.
Instead of the old belt-driven fans, eight new RadiFit centrifugal fans now provide fresh air. (Photo | Lukas Zwiessele)
The system’s control cabinet was still in good condition. It was modernized, including a new control and an ebm-papst neo gateway.
A new control system does not always suffice, but completely replacing the systems is expensive and time-consuming. When looking for a partner for difficult modernization projects, the two brothers were aware of the retrofit projects of the ebm-papst Service Center Breuell & Hilgenfeldt. Since then, they have been implementing these types of upgrades in collaboration with the fan manufacturer from Mulfingen and retrofit expert Dieter Hildebrandt from Breuell & Hilgenfeldt.
Old system, new control?
For the Beutelsbach Stiftskeller, the task was to only modernize the ventilation system’s control system. “We took a look at the control cabinet on site. It was still in good condition. But we were taken aback when we looked at the ventilation: old belt-driven fans were still installed.” A new control system for an old system? As a result, the greatest potential for savings would be unused.
Our aim was to reduce the ventilation system’s energy consumption by at least 60 percent.Lukas Pfänder, Managing Director Pfänder GmbH
Dieter Hildebrandt’s suggestion: eight new RadiFit centrifugal fans in four systems that supply fresh air to the vaulted cellar, gym, showers, changing rooms, and cinema much more efficiently. The ventilation shafts in a good condition and the limited space in the cellar were perfect conditions for a retrofit: System open, old fans out, RadiFit in.
Saving energy, sixty percent and more
They then went to look at the electrics in the control cabinet. The Pfänders read the new ventilation system’s performance values for the first time: “Our aim was at least 60 percent less current consumption. This permits infinitely variable regulation of the RadiFit EC motor.
Instead of two stages that correspond to a power of 0 or 100 percent, we can now call up outputs of 16, 37, or 89 percent as required.” The 60 percent savings target was already achieved by replacing the fans, but there was still room for improvement.
This is because there is even more efficiency to be had if the demand is precisely identified and automatically controlled. The rooms of the Stiftskeller are perfectly suited to this, as Lukas Pfänder explains: “The gym is not used for half of the day. However, if there is a lesson being taught there, the CO₂ content increases sharply and, therefore, the demand for fresh air rises significantly too. After the lesson, the showers and changing rooms are used, causing high temperatures and humidity.”
With demand-based control, the ventilation system reacts independently to these rapidly changing requirements. The replaced control cabinet already offered the right conditions for this. All that was missing was sensors and gateways. Dieter Hildebrandt recognized the opportunity and presented Lukas and Tobias Pfänder with gateways from the start-up ebm-papst neo, which deals with intelligent solutions for data-based buildings.
Sensors make it smart
The sensors continuously measure CO₂ content, humidity, temperature, and fine dust concentration in the air. The values are sent to the Intelligate Air Gateway, which forwards it to the ventilation system control system. The control system has been individually adapted and programmed for the Stiftskeller. If the CO₂ value in the vaulted cellar or the humidity in the shower exceeds a certain limit value, the system automatically adjusts up and back down once the air quality is good and, thanks to the EC motor, this is done smoothly and efficiently.
We have perfectly tailored the control system to the requirements of the monastery cellar to save even more energy. Lukas Pfänder, Managing Director Pfänder GmbH
Ralf Braun, Sales Director for Germany at ebm-papst, explains: “Of course, you can also adjust it manually. However, the interaction between the sensors and the system is very reliable and, above all, economical.” Individual functions, such as sending a warning to the building’s caretaker by e-mail, are also possible if a certain value is exceeded. “This ensures a very high air quality on an ongoing basis. After the last few years and especially at larger events, that is a good feeling,” says Braun. Therefore, visitors to the monastery cellar can feel completely at ease. Thanks to the retrofit, in addition to efficient ventilation, the quality of the air is ensured at all times.
Next-level air quality
With the Multi-IAQ sensor from ebm-papst neo, there is a simple and efficient way of ensuring consistently high air quality in event rooms. The sensor measures a total of five values, namely temperature, humidity, VOC (volatile, organic compounds that are harmful to health), CO2, and fine dust in the air. The viral index is calculated using the five measured values and a complex mathematical equation. This indicates the quality of the air and the risk of virus transmission and can be read off from the freely accessible IAQ Connect app. The multi-IAQ sensor can be installed in flush-mounted sockets similar to a light switch.