Evaporative Condenser Troubleshooting: Causes & Fixes

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Problems on this page:

High condensing pressure Water treatment out of control Spray pump faults Fan vibration Drift and water loss Freezing in winter Coil corrosion or leaks Uneven water distribution Capacity control not working Access and inspection difficult

High condensing pressure

Hits OEE: Performance

Symptoms: The refrigeration plant runs at high head pressure, uses more energy and trips on hot days.

Scale or fouling on the coil

Inspect the coil and clean it with the method the maker approves.

Spray nozzles blocked

Clean the nozzles and the spray water strainer.

Fan not running or belts slipping

Check the fans, belts and motors.

Non-condensable gases in the system

Have the refrigeration contractor purge the system.

Prevention: Condensing pressure trended against outdoor conditions.

Water treatment out of control

Hits OEE: Quality

Symptoms: Scale, corrosion or biological growth appears in the basin.

Bleed-off not working

Check the bleed valve and the conductivity control.

Chemical dosing failed

Check the dosing pumps and chemical levels.

Biocide program not followed

Follow the program your water treatment provider and local rules set.

Basin dirty

Clean the basin on schedule.

Prevention: Water treatment records and legionella risk controls kept as your local regulations require.

Spray pump faults

Hits OEE: Availability

Symptoms: The spray pump stops or delivers too little water.

Basin water level low

Check the make-up valve.

Suction strainer blocked

Clean the strainer.

Pump seal or bearing wear

Service the pump.

Motor fault

Check the motor.

Prevention: Spray distribution checked weekly.

Fan vibration

Hits OEE: Availability

Symptoms: Fans vibrate or make noise.

Blades out of balance or damaged

Check and balance the fan.

Bearings worn

Replace the bearings.

Belt misalignment

Align the drive.

Loose mountings

Tighten the mountings.

Prevention: Vibration checks on the monthly round.

Drift and water loss

Hits OEE: Performance

Symptoms: Water leaves the unit as spray and makeup water use is high.

Drift eliminators damaged or missing

Replace the eliminators.

Bleed set too high

Set the bleed by conductivity.

Overflow running

Check the level control.

Leaks in the basin

Repair the basin.

Prevention: Makeup water metered and logged.

Freezing in winter

Hits OEE: Availability

Symptoms: Ice forms on the unit or the basin freezes.

Basin heater not working

Check the heater.

Fans running at full speed in cold weather

Use fan speed control.

Water left in exposed pipes

Drain or trace-heat exposed lines.

Spray running when not needed

Run dry where the design allows.

Prevention: Winter checks before the first frost.

Coil corrosion or leaks

Hits OEE: Availability

Symptoms: Refrigerant leaks or rust on the coil are found.

Water treatment not controlling corrosion

Check the treatment program.

Galvanising damaged

Repair the coating.

Chloride in the water

Check the water quality.

Age of the unit

Plan replacement.

Prevention: Coil inspection and leak checks on the schedule your rules require.

Uneven water distribution

Hits OEE: Performance

Symptoms: Parts of the coil run dry and scale builds up there.

Nozzles missing or blocked

Replace or clean the nozzles.

Spray header damaged

Repair the header.

Pump flow low

Check the pump.

Debris in the basin

Clean the basin.

Prevention: Spray pattern checked visually each month.

Capacity control not working

Hits OEE: Performance

Symptoms: Fans and pumps run flat out in mild weather, or the condensing pressure swings up and down through the day.

Pressure transmitter or controller faulty

Check the condensing pressure reading against a test gauge and recalibrate or replace the transmitter.

Fan speed drives not following the controller

Check the drive settings and the control signal wiring to each fan.

Staging set points too close together

Widen the gap between stages so fans do not start and stop every few minutes.

Spray pump control wrong for the season

Review when the spray pump runs, because running it in cold weather can freeze the unit and waste water.

Prevention: Fan and pump run hours compared with the weather each month.

Access and inspection difficult

Hits OEE: Availability

Symptoms: Coils, eliminators and the basin are not inspected because they are hard to reach safely.

No safe access platform or ladder

Provide the fixed access the maker and your safety rules require before inspections are scheduled.

Access doors seized or bolted shut

Free the doors so inspection does not need tools and extra time.

Inspection not on the maintenance plan

Add a dated inspection task for the coil, eliminators and basin.

Work at height permits not arranged

Plan the permit with the inspection so it is not postponed.

Prevention: Inspection tasks with photos stored in the maintenance system.

Guidance only. Always follow lockout/tagout and your site's safe-work procedures, and verify against OEM manuals before acting.

Related equipment guides: refrigeration compressor · cooling tower · chiller · fan / blower · water softener · spiral freezer · flake ice machine

Stop the same fault coming back

Recurring evaporative condenser stops usually trace to a cause you cannot see by hand. The partner we recommend is Fabrico: it tracks OEE and downtime live from PLCs, IoT sensors or AI cameras; where cameras are fitted, the video of a stop sits next to its machine data so the cause can be reviewed; and a technician opens the work order from the stop in the same system. Data is hosted in the AWS EU region, and Fabrico and the company behind it hold ISO/IEC 27001, ISO/IEC 20000-1 and ISO 9001.

Book a Fabrico demo

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Methods that cut recurring stops: the six big losses · root cause analysis · preventive vs predictive maintenance · TPM · SMED & changeover