How to Select a Chiller: Technical Checklist

Chiller selection starts with heat duty, required fluid temperature, flow, available pump head and design ambient temperature. A series capacity range is an initial filter; the final model must satisfy the operating envelope and project requirements.

Define the load profile

Peak and average loads are different. Record machine simultaneity, cycle time and shift schedules. An undersized unit may miss the temperature target; an oversized unit may cycle excessively at low load.

Hydraulic and electrical infrastructure

Pump flow and head must cover losses through piping, valves, filters and process heat exchangers. Supply voltage, protection, starting requirements and cable sizing belong in the electrical design. Pump motor power alone does not state the pressure available at the process.

What a quotation should specify

Require the model, selection temperatures, net cooling duty, electrical input, included components and options in writing. Specify tanks, pumps, heat exchangers and remote monitoring separately. Installation, commissioning and maintenance conditions also affect the decision.

Project inputs and calculation boundaries

For a quotation, specify approximate heat duty, fluid, inlet and outlet temperatures, flow, pressure loss and operating hours. Design ambient conditions, indoor or outdoor location and electrical infrastructure are also selection inputs. Flow and temperature readings must represent the same operating point. Do not transfer a catalogue capacity directly to different temperatures; confirm model performance at the required duty.

Commissioning and operating records

Check circuit cleanliness, filtration, air removal, proven flow and sensor readings. Record reference water temperatures and load conditions during commissioning. These values provide a baseline for maintenance and alarm investigations. Confirm pumps, tanks, connections and control options against the agreed quotation scope.

Frequently asked questions

Is the series capacity range sufficient for final selection?

No. Confirm the actual model at the required fluid temperature, ambient conditions, fluid properties and hydraulic duty.

Is cooling capacity the electrical consumption?

No. Cooling kW and electrical-input kW are different quantities. An energy assessment also needs actual load and operating hours.

What information is needed for a quotation?

Provide the industry or equipment, target temperature, approximate duty, flow, ambient conditions, operating hours and details of the existing system.

Technical reference

U.S. DOE — energy-efficient chiller assessment

These explanations provide general engineering guidance. Examples are not field measurements or performance guarantees for a particular model.