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Which type of cooling for serverrooms is the right one?

Which type of server or IT-room cooling should I choose?

For many companies, the aspect of cooling server- or IT-rooms is more relevant than ever. This has several causes. The main one is the increase in data traffic (due to, for example, the increase in working from home) and the rising temperatures worldwide (global warming). As a manufacturer of cooling for these smaller server rooms, we encounter many different situations that can be improved by means of our climate solutions. We are happy to advise you on this. In this article, we explain two of our climate solutions and compare them with each other. These are the EC-Tower and the MiniSpace EC. Two different climate solutions, each with the same goal. Which solution is right for you?

Introducing: The EC-Tower

In contrast to a regular comfort split system, the EC-Tower is an efficient and complete cooling solution for smaller server- and IT-rooms. The EC-Tower is characterized as a total solution, in terms of ease of installation and variable cooling capacity at low energy costs. The EC-Tower is available in cooling capacities from 2.3 - 52.0 kW and is standard equipped with steam humidification and electrical reheating. The inverter compressor seamlessly adjusts the cooling capacity to the heat load. Pre-filled refrigerant is also standard, suitable for up to 15 or 30 meters of refrigerant pipe length, depending on the type selected.

The largest capacity of this series, the 52.0 kW variant, is a very reliable solution because of the two separate evaporator coils in the indoor unit, each of which is connected to its own individual outdoor unit with separate inverter compressor and condenser.

The installation is relatively simple due to the use of a comfort split system outdoor unit and the same standard connection dimensions on both the indoor and outdoor unit. This means that the installation and assembly is no problem for the professional installer.

Introducing: The MiniSpace EC

With the MiniSpace EC you get the same high-quality precision cooling technology, as for cooling large or hyperscale data centers, but tailored for smaller server- and IT-rooms The MiniSpace EC can be individually selected for you with different options, capacities and designs. The unit has a cooling capacity of 5.0 - 25.0 kW and is available in a direct expansion (DX) version, a chilled water (CW) version and a G-system DX with plate heat exchanger (condenser) that runs on an existing cooling water network or can be connected to a dry cooler.

The MiniSpace EC units require little floor space, the unit comes in two sizes. Construction size 1 of 600 x 600 mm (the size of a computer floor tile) and construction size 2 of 1,000 x 810 mm. The compact size generally means that the units can be integrated into existing server- or IT-rooms without further modifications. The MiniSpace EC also offers extra benefits with the optional Direct Free Cooling function which provides energy savings of up to 90%.

How do you make the choice between those two systems?

In order to be able to choose between the EC Tower and the MiniSpace EC, you must take several aspects into account. If you have a variable heat load that falls into one of the ranges of the EC-Tower (see table 1), the EC-Tower distinguishes itself significantly in terms of simplicity due to the standardized complete unit. The installation of the system is comparable to the installation of the well-known comfort split systems.

When a fixed heat load or/and customization is required, or when special circumstances arise, the MiniSpace EC is more suitable than the EC Tower. The Minispace EC is flexible when it comes to customization in capacity, air flow and the optional components that can be selected. The MiniSpace EC requires more expertise in refrigerant pipe design and installation. If the requested cooling capacity exceeds 25 kW, a "larger" solution with the CyberAir must be considered, which is also offered as customization. In summary, the MiniSpace EC is the right solution for customization, where with the EC-Tower you opt for a standardized unit with the additional ease of installation.

We hope this article can help you choose the right cooling solution for smaller server- and IT-rooms. But whatever choice you make, the EC Tower or the MiniSpace EC, you will get an air conditioning unit which is developed to help you with your server- or IT room and is equipped with a complete set of features. For example, both EC Tower and MiniSpace EC are standard equipped with a common alarm contact, the possibility to link him to your existing Building Management System (BMS) via Modbus RTU protocol and a variable-speed fan with a high motor efficiency up to 92% which leads to savings in operating costs. This is just a short summary of the functions both units have to offer.


Table 1Nominal sensible Cooling capacity kWEC-Tower set with outdoor unit selection

2,3 – 4,5 kW 1x EC-Tower 91 D/U
1x SRC 50 ZSX-S
2,8 – 6,8 kW 1x EC-Tower 91 D/U
1x FDC 71 VNX
5,0 – 9,3 kW 1x EC-Tower 181 D/U
1x FDC 140 VSA
5,0 – 10,8 kW 1x EC-Tower 181 D/U
1x FDC 140 VSX
7,0 – 17,5 kW 1x EC-Tower 181 D/U
1x FDC 200 VSA
10,0 – 21,4 kW 1x EC-Tower 251 D/U
1x FDC 250 VSA
7,0 – 44,7 kW 1x EC-Tower 502 D/U
2x FDC 250 VSA

If you would like more information, please do not hesitate to contact us. Our experts are happy to advise you at every stage of the process.