42 www. refrigerationandaircon. co. za RACA Journal I March 2026
MICROCHANNEL HEAT EXCHANGERS voices
Where they don’ t quite match up, is in the maintenance and
Our regular choice will invariably be in favour of the tried-andtested copper tube / aluminium fin coil construction for as long as durability stakes:
• They are prone to premature clogging( due to the these remain available. However, if a‘ tight budget’ dictates the microchannel design) chiller selection, we will ensure that the client is made aware of
• Less durable due to their all-aluminium construction( handle the risks involved. the chiller with care from production line to site)
Currently one has the choice:‘ new age’ microchannel
• Leak repair is difficult( two epoxy process or gas torch repair) super-efficient condenser, or the‘ old school’ well proven durable
• Requires precise refrigerant charge( easy to overcharge aluminium fin on copper tube condenser. system) – proper charge is critical Going forward, we firmly believe that the problems
• Prone to leaking due to ultrasound harmonic vibration, besetting the MCHX coils will in due course be overcome, incorrect cleaning methods and overcharging the system, etc. as new materials and
1 and 2: Oil mist on the coil face indicating a refrigerant leak in close vicinity.
1
2 technology evolves. We can only wait and see. In the meantime, both budget-cost chillers and the highercost more robust( durable) offerings are readily available to the end-user, thereby catering for both sides of the spectrum.
Nevertheless, like everything in the engineering world, proper communication, instruction and user training is essential when encountering any new form of technology. Never – and I repeat, never – simply apply the‘ old’ way of doing things. You could land up with a great deal of egg on your face, not to mention the damage to your ' s and your company’ s, reputation.
Remember, when all else fails, read the instructions, then read them again for good measure.
At the end of the day, the client needs to get what he is paying for, nothing more, nothing less. He must be made completely aware of the pros and cons determining any final decision. That’ s your obligation and commitment. Achieve this and you will have a client for life. RACA
42 www. refrigerationandaircon. co. za RACA Journal I March 2026