Primary vs Secondary Chilled Water Pumps

Understanding your system's flow strategy.
Choosing the right pumping configuration—primary-only, primary-secondary, or variable primary—is essential for chiller plant efficiency, stability, and cost. EKG Malaysia provides expert design review, balancing, and optimisation for all configurations, ensuring your system meets performance and energy goals.

Primary Pumps

• Role: Circulate water through the chiller(s) only.

• Flow: Typically constant speed to meet the chiller's fixed flow requirement.

• Goal: Protect the chiller and ensure stable evaporator operation.

Secondary Pumps

• Role: Circulate water through the building load (AHUs, FCUs).

• Flow: Usually variable speed, responding to changing cooling demand.

• Goal: Maintain comfort while saving energy at part load.

Common System Designs:

Primary-Secondary (Decoupled) System

• Uses a common pipe to hydraulically separate the two loops.

• Best for: Systems with multiple chillers, retrofits, or where chiller protection is the priority.

Variable Primary Flow (VPF) System

• A single set of variable speed pumps serves both the chiller and building.

• Best for: Modern plants with variable-flow chillers. Offers the highest pump energy savings.

Why It Matters in Malaysia:

• Part-load efficiency is critical—systems often run at 40–70% load.

• Correct design prevents Low Delta-T Syndrome, a major energy waster.

• Supports GBI / Green Building certification through optimized operation.

EKG’s Service:
We provide design review, commissioning, and optimisation to ensure your pumping strategy is correctly implemented, stable, and efficient.

Get the right hydraulic design.
The optimal setup balances performance, energy savings, and reliability.

Contact EKG Malaysia to design, verify, or optimise your chilled water pumping system.