In closing, the engineer should always give close attention to each of the various factors that will ultimately influence his final decision on the way forward, be it initial cost, operating costs, client relations, longevity, environmental impact and the like.“ Protecting the coil against corrosion is paramount for ensuring optimum operating life.” RACA Continued in part two … www. refrigerationandaircon. co. za 39
MICROCHANNEL HEAT EXCHANGERS
new top-end 800kW( r) air-cooled chiller, at today’ s rates, is in the order of +/- R3.2-million – excluding installation costs.
Other challenges facing the use of MCHEs are:
• Limited infrastructure and technical support facilities
• Space availability
• Lack of skilled technicians familiar with MCHE technology
• Difficulty in achieving effective leak repairs in the field
• Challenges in achieving the correct refrigerant charge voices
Monetary constraints due to higher initial manufacturing costs and the need for specialised maintenance can be a barrier for widespread acceptance, particularly in cost-sensitive markets.
As previously mentioned, the real possibility of refrigerant leaks can be particularly problematic due to the high cost of each heat exchanger replacement panel. This and the difficulty in effecting a permanent repair( in the event of a leak) has no doubt led to a degree of resistance to the wider use of MCHEs in the field.
Vibration is widely thought to be a possible factor when addressing the refrigerant leak issues associated with an air-cooled chiller installation, although no conclusive evidence has been proved to date. Nevertheless, it would be prudent to ensure the installation of adequate anti-vibration mountings as a matter of course, with the view to eliminate any high-frequency‘ vibration harmonics’ that could well be associated with the various chiller components once installed.
Packaging, delivery and handling of the chiller from point of manufacture to site, is an extremely important aspect
RACA Journal I February 2026
for consideration. Proper handling, shipping and site control management is essential, due to the delicate nature of the aluminium materials used.
In closing, the engineer should always give close attention to each of the various factors that will ultimately influence his final decision on the way forward, be it initial cost, operating costs, client relations, longevity, environmental impact and the like.“ Protecting the coil against corrosion is paramount for ensuring optimum operating life.” RACA Continued in part two … www. refrigerationandaircon. co. za 39