The needs for economical, low-power cooling for electronics enclosures are said to be met by the MHC series of core-type heat exchangers and MHH series of heat pipe heat exchangers. The MHC series achieves high heat transfer performance and compactness with an efficient impingement cooling system for cooling at above ambient. The series features as closed loop system maintaining NEMA 12 cabinet integrity, reduced fan noise, and long life. The MHH series of heat pipe heat exchangers provides economical above ambient cooling to electronics enclosures. With the utilization of a heat pipe to dissipate heat, power consumption is said to be greatly reduced in cooling the enclosure's interior air temperature.