rack-mounted cooler system for computers

[NoNickName]

Yeah, that's a commonly installed system. Please contact Aquacooling http://www.aquacooling.co.uk/ . They will also supply a system for leak prevention under negative pressure.
Don't forget that a leak in the door coil would spray the computers.That's where a negative pressure system comes handy.

[r.bartlett]

Rittal do both versions. a DX door or roof mounted cabinet cooler or a water cooler version

http://www.rittal.co.uk/products/sys...rol/index.html

They also do a very high spec server room cooler but that will be well outside your budget