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PLANT-02 · Central plant

Low chilled-water ΔT syndrome

The chilled-water loop's supply-to-return delta is below design when the chiller is loaded.

Capacity-basedBAS trendsMedium effort

What does PLANT-02 mean?

The chilled-water loop's supply-to-return delta is below design when the chiller is loaded.

Why does it matter?

Low ΔT means the loop is moving more water than the load actually needs. CHW pump power goes up cubically with flow, chillers run at low efficiency, capacity is artificially limited. A classic — and expensive — pumping syndrome.

What should you do?

Check coil valves for being stuck open (most common cause), 3-way valves bypassing flow, decoupled bridge balance, and CHW pump control sequence.

How Energy Agent prices a finding

Written by Pelorus Engineering · Brent Waluzak, P.E. (FL), President, Pelorus EngineeringLast updated
Estimate it

What is low ΔT costing in pumping?

Estimate the extra pump energy from moving more water than the load needs.

Enter a repair or controls-change cost to see the simple payback.
Avoidable cost per year—Energy —Simple payback Enter a cost to fix to see the payback.

    Pump power rises with the cube of flow. At design ΔT the loop needs only (actual ÷ design) of today’s flow, so pump power at design would be that ratio cubed. Energy Agent measures ΔT and pump power from the plant trends.

    Screening estimate. Energy Agent measures the real fault hours and load from your trends and prices them at your tariff.

    Request a demoSee how Energy Agent prices a finding

    Screening-level estimates; confirm with measurement and verification before capital commitment.

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