DC Tower is the tallest building in Austria. The iconic landmark in the heart of Vienna houses dozens of businesses on its 60 floors. In 2022, one of the building’s two 2MW centrifugal chillers was damaged in an electrical fire. With capacity already halved, the building managers were very concerned that if the second chiller also failed, the building would be left without any cooling capacity. The building’s innovative folded glass façade means there is a need for air conditioning even in winter as well as cooling in the building’s server rooms.

For the building managers, the situation was a matter of urgency: if they were unable to source a rapid and reliable chiller replacement, customers and the rest of the occupants comfort would be greatly impacted, jeopardizing all of the building businesses. They potentially also faced very costly rent rebate demands from tenants. As well as offices, the building contains apartments, the 5* Melia Vienna hotel and a top-floor restaurant and sky bar.


The customer reached out to Trane Rental Services and the local Austrian team was able to visit the 250m-high building within a couple of hours.

It swiftly became clear that using externally-sited, air-cooled chillers would not be possible; a street lay above the building’s basement chiller plant room and there was no outdoor space. This meant that a creative approach was needed to provide an appropriate solution. Trane Rental proposed the use of indoor water-cooled chillers equipped with scroll compressors which could be brought down to the plant room via the building’s elevators.

The Trane Rental Services team needed to devise a solution using units that could fit into the building’s elevators and not exceed the elevator weight limits.

Four small footprint water-cooled scroll units were supplied to provide a total capacity of 1800 kW.

The units were disassembled as much as possible before being placed in the elevators but nevertheless, it was a very tight fit.


The rental period started during the summer of 2022 and lasted around eight months while the building’s existing centrifugal chiller was being repaired.

The customer was relieved to be able to rely on Trane Rental’s swift response and can-do approach to the installation challenges.

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Project highlights

Location: Austria

Market application: Office building

Customer need: Emergency comfort cooling: 1800 kW

Products installed: 4 x CGWN water-cooled scroll units

Cooling Capacity: 1700 kW

Featured products

Product name: City Advantage CGWF/CCUF Water-Cooled Chiller

At a glance:

  • SEER: Seasonal efficiency up to 7.31 under EN14825:2018 conditions
  • Compact: 880 mm maximum width
  • Quiet operation: low vibrations; available in both low or super low noise versions

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