guide
CDU comparison guide
How to compare coolant distribution units fairly: which fields matter, why capacity only means something at a stated approach temperature, flow and fluid, and a table of published CDU data with every missing value marked not disclosed rather than guessed.
Why a CDU comparison needs rating conditions
CDU capacity depends on the approach temperature difference (ATD) between facility water in and technology coolant out, on TCS flow per kW and on the fluid. Published figures show how much this matters. Eaton rates one ROL unit at 2,300 kW with an 8 °C approach and 1,150 kW with 4 °C. LiquidStack rates its CDU-1MW between about 1,004 kW and 1,350 kW depending on flow per kW. Compare products only at the same ATD, flow per kW and fluid.
Fields to compare
Architecture (liquid-to-liquid or liquid-to-air). Location (in-rack, in-row, facility or skid). Capacity with ATD, flow per kW, fluid and supply temperatures. Flow and available pressure. Pump and filter redundancy. Filtration grade. Fluid compatibility and wetted materials. Controls protocols and group control. Footprint and weight. Electrical supply. Product status (prototype, announced, orderable, shipping). Regional service in the project country.
How to read the table
Rows come straight from published supplier records on this site, each linked to its source. Where a field is blank on the supplier's own page it reads not disclosed. A missing value is not a weakness of the product, only a gap in public information, so ask the supplier. Status reflects the supplier's own wording on the date checked.
Normalising quotes
Ask every bidder to state capacity at one agreed point, for example 4 °C ATD, 1.5 lpm/kW, PG25 TCS, with your facility water temperature. Ask for pump power at that point and for part load curves. Check whether quoted capacity assumes N or N+1 pumps running.
What we could not verify
For most products, fluid compatibility lists, certifications and evidence of service teams in specific countries were not published. Several new models are announced but not yet shipping. The supplier pages are the authority and may change.