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PLANT-06 · Central plant

Cooling-tower fan short-cycling

The cooling tower's fan is starting and stopping more frequently than its minimum-runtime allows.

Capacity-basedBAS trendsMedium effort

What does PLANT-06 mean?

The cooling tower's fan is starting and stopping more frequently than its minimum-runtime allows.

Why does it matter?

Hard on the gearbox, motor, and VFD. Also wastes the inrush current and prevents stable condenser-water control.

What should you do?

Investigate the tower control sequence — is staging hunting? Is the CW supply setpoint too tight? Consider a longer minimum-on timer.

How Energy Agent prices a finding

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

What is short cycling costing?

Estimate the energy wasted on starts, and remember the wear is the bigger bill.

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.

    Each start costs roughly a couple of minutes of full-load energy before the unit is doing useful work. Extra starts above a sane rate, times that penalty, times the unit size and the affected hours. Energy Agent counts the starts from status 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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    Send twelve months of interval data and a BAS trend export. Energy Agent returns a ranked list of what is wasting money, what each item is worth per year at your tariff, and what to do about it.

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