FAQs - Liquid Cooling

The advantages of liquid cooling over traditional air conditioning include higher heat transfer performance, improved thermal control, lower energy consumption, increased server rack densities and lower noise levels.

The disadvantages include the potential for fluid leaks, which can be catastrophic, the need for servers, storage devices and GPUs to be compatible with immersion cooling systems, the specialised service procedures required, and environmental considerations including end-of-working life fluid disposal of a potentially hazardous substance, some of which may be less environmentally friendly than others (i.e. PFA – Perfluoroalkoxy alkane – referred to as a ‘forever chemical’).

Liquid cooling is more efficient than air cooling as the dielectric liquids used have a higher thermal conductivity and heat capacity, than air. These properties allow liquids to absorb and transfer heat much faster and more effectively, enabling lower operating temperatures and higher performance for server components including CPUs and GPUs.

Liquid cooling systems require more specialized maintenance than traditional air-cooled systems, including the type of computer room air conditioners used in server rooms and data centres.

Liquid cooling systems required regular cooling quality checks, potential system flushing, leak detection and temperature monitoring. Whilst temperature and spot water leakage detection is important for air-conditioned environments, liquid systems raise the risk of coolant leaks and require more specialist handling and monitoring of the dielectric fluids used.

There are two main technologies for liquid cooling in data centres. The first is known as “Direct-to-Chip Liquid Cooling” which uses cold plates attached directly to key components like CPUs and GPUs. A liquid coolant is circulated through the plates, absorbing heat from the hardware and carrying it away to a heat exchanger. The second is “Immersion Cooling” where the entire servers themselves are submerged in a non-conductive (dielectric) liquid. The liquid absorbs heat directly from all components, offering very high cooling efficiency and eliminating the need for most traditional air-based systems.