Unusual noises in the Media Markt store in Berlin-Wedding got the atten­tion of tech­ni­cians from Daume, a building equip­ment specialist. They were actu­ally there to do other construc­tion work and noticed a sporad­i­cally occur­ring rota­tion noise: a motor bearing failure about to happen in the air supply system. If a failure occurred, things would get stuffy for the store’s customers and its employees. “The system was still running with a belt-driven housed fan from 1995. The tech­nology has made a lot of progress since then,” says Marco Mitter­müller, head of customer service at the Daume Group in Berlin.

The entire range

Mittermüller’s employer is an owner-managed group of compa­nies head­quar­tered in Duder­stadt. It supports public sector, commer­cial and indus­trial customers in all aspects of building equip­ment: heating, cooling, venti­lation, sani­ta­tion, and measure­ment and control systems. Daume looks after all of the Media Markt and Saturn stores in Germany; there are 29 of them in Berlin alone.

First one, now six

For the assign­ment at the store in Berlin-Wedding, Daume brought ebm-papst on board. The plans called for the venti­lation system to provide air condi­tioning for 4,000 square meters of floor space on two floors. The solu­tion: six RadiPac EC centrifugal fans connected in parallel in a FanGrid. They could fit in the existing air handling unit.

Compar­ison of air flow through the RadiPac FanGrid ...

... and the belt-driven centrifugal fan.

Manage­ment at the Media Markt store didn’t have to think twice; the expected amount of energy savings was convincing enough. The project was imple­mented within three months. “That’s not incred­ibly fast, but compared with other projects, the deci­sion-making phase was much shorter than usual because of the worries that the system could fail,” says Mitter­müller.

“Most customers dream of amor­ti­za­tion periods of less than a year.” 

Marco Mitter­müller, Daume

A major benefit of the project is that Media Markt can save 70 percent on elec­tricity. As Mitter­müller says, “Compared with current models, the old fans use up lots of elec­tricity.” The change from belt-driven AC fans to the FanGrid with fans from ebm-papst has reduced the Media Markt store’s annual elec­tricity bill from 18,651 to 5,367 euros. “Most customers dream of amor­ti­za­tion periods of less than a year. In this case, and of course accounting for the repair costs, we were able to realize that,” says Mitter­müller.

When­ever there’s room for improve­ment

Marco Mitter­müller says, “We can rely on ebm-papst. When­ever we rebuild venti­lation systems with EC fans, we always work with ebm-papst – in other words, when­ever there’s room for improve­ment.”

The belt-driven fan’s drive motor was damaged. Quick action was called for. (Photo | Daume)

A giant blower was aimed at the heat exchanger. (Photo | Daume)

Since the deci­sion in favor of the conver­sion was made quickly, Daume was able to begin disman­tling the old system without delay. (Photo | Daume)

Every­thing still fits. The housing can stay. (Photo | Daume)

After the conver­sion: six brand-new EC fans ready to go to work. (Photo | Daume)