Three different jobs
Chillers appear in compressed air systems in three places, and confusing them leads to the wrong specification.
- Cooling the compressor - water-cooled machines reject heat to a water circuit instead of to room air, which suits hot or enclosed plant rooms.
- Cooling the dryer - a refrigerated dryer uses a refrigerant circuit; a water-cooled condenser moves that heat into water rather than air.
- Cooling the process - some processes need chilled water directly, and the compressor is simply another heat source on the same circuit.
Why water cooling is chosen
Water carries heat away in a smaller volume than air, so a water-cooled package is quieter and less dependent on room ventilation. The trade is that the heat has to go somewhere: a cooling tower, a chiller or a process water loop. If that loop is undersized or runs warm, the compressor inherits the problem.
Sizing the loop
Match the water flow and inlet temperature to the machine's heat rejection, not to the pipe size. Allow for the tower or chiller being unable to hold its design temperature on the hottest days, and set alarms on the water temperature rather than relying on the compressor's own high-temperature trip.
Maintenance that gets skipped
Water quality matters more than most sites expect. Scale on a heat exchanger reduces capacity quietly, and fouling on the water side is invisible until the machine derates. Strainers, water treatment and an annual inspection of the exchanger are cheaper than a replacement.
Send us your working pressure, required flow and site conditions and we will propose a configuration. Contact OPPAIR.