Compressor selection depends on load profile, capacity control, operating temperatures and maintenance requirements. Scroll, parallel-scroll and screw solutions cannot be divided by a single universal capacity threshold.

Single and multiple scroll arrangements

A single compressor and staged multiple compressors have different minimum-load behaviour. Oil management, circuit design and staging logic matter in tandem and multiple arrangements. Multiple compressors do not automatically provide N+1 redundancy.

Screw compressors

Screw equipment can be considered for larger duties. Compare capacity-control method and part-load efficiency using actual model data. A screw unit is not inherently more efficient than every scroll alternative at every load.

Reading Vega tables

VG SS is presented as single scroll and VG DS as twin scroll. The VG MS table lists 4, 6 or 8 compressors depending on model; the whole series must not be described as four-compressor equipment. Use verified model data and quotation scope for VG DW.

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

Copeland — multiple scroll arrangements

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