Temperature Range - Select the chiller based on the temperature range required. Some applications require very low temperatures so it is best to start by confirming the temperature range of the chiller matches your application.
Cooling Power - Select the chiller which has sufficient cooling power at the temperature required. Chiller manufacturers often list the cooling power at various temperatures. Always consider losses and select a chiller that is at least 25% bigger than what is needed (note that the cooling power at the lowest temp is 0).
Power requirements - For smaller chillers 120V power is often used by default but larger chillers often use 230V to 460V single and three phase power.
Environment - Air cooled chillers require space around them to exchange air. If there is not sufficient air flow or the air is too hot the chiller will not work correctly. In some cases it may be best to use liquid cooled chillers, especially if the room is small or too hot.
Pump Pressure and Flow
Turbine Pumps – Provide moderate flow and moderate pressures
Positive Displacement Pumps – Produce moderate flow at high pressure
Centrifugal Pumps (Magnetic Drive) – Offer higher relative flow rates at lower pressures