Carrier 30XA, 30RB and AquaEdge chillers manufactured before 2020 ship with three-row copper-aluminum condenser bundles that weigh up to 650 kg per section and hold 180 kg of refrigerant. Kaltra now produces microchannel coils for Carrier chillers using aluminum multi-port technology that rejects identical heat duty in 45 % less face area while holding only 110 kg of charge, translating into 1 600 € annual carbon-tax savings on a 700 kW machine.
Flat tubes contain twenty to ninety ports 0.7 mm wide, pushing internal heat-transfer coefficients above 5 kW m⁻² K⁻¹. The geometry keeps air-side pressure drop below 65 Pa at 2.5 m s face velocity, so fan current falls 25 % and sound power follows the same curve.
Kaltra vacuum-brazes every joint at 600 °C under nitrogen, creating a monolithic block rated for 30 bar working pressure and 200 °C continuous temperature. The all-aluminum core eliminates galvanic corrosion, giving microchannel coils for Carrier chillers a 20-year design life in coastal or urban atmospheres without protective coatings.
Headers are CNC-machined to Carrier drawing numbers, ensuring original inlet/outlet positions, bolt patterns and casing dimensions. The coils slide into existing rack rails without moving fan decks, control boxes or structural steel, cutting installation time to one shift. Integral sub-cooling circuits recover 7 K of liquid temperature, raising chiller COP by 3 % and reducing compressor lift during peak summer afternoons.
Weight drops from 650 kg to 450 kg per section, removing 200 kg of roof load and allowing retrofit projects to reuse existing rigging chains and curb layouts. Fin spacing is selectable from 18 to 22 FPI, letting engineers balance capacity versus sound power when fans operate at night-time reduced speed.
Kaltra’s sizing portal embeds AI routines trained on 50 000 laboratory tests. Enter Carrier model number, capacity and ambient conditions, and the code returns exact microchannel coils for Carrier chillers with validated performance curves, fan power and live price within 60 seconds. Export packages include STEP files, wiring diagrams and ERP-ready BOMs, so procurement and service teams work from the same dataset.
Production capacity reaches one million cores per year across facilities in Graz and Plzeň, with fourteen vacuum-brazing furnaces operating 24/7. Standard lead time is ten working days; emergency batches ship in 72 hours, pre-brazed, pressure-tested to 52 bar and dried to −40 °C dew point.
Users benefit from lower operating costs, smaller carbon footprint and faster maintenance
turnaround. Charge reduction shortens pump-down time by 30 %, while lighter modules cut hoisting fees and roof reinforcement expenses. The result is a drop-in upgrade that extends chiller life by another two decades without structural modifications.
