Lowering of temperature drop across Cooling Tower Fills condition is poor Replace / Clean Fills
Fan not in operation Check motor, put fan in operation in correct direction
Distribution of water through Nozzles on Fills not correct Clean the Nozzles
Change in design parameters as water flow rate, Air flow rate Check Pump flow rate, plant load, Clean Heat transfer surfaces wherever possible adjust Fan blade angle
Wet Bulb temperature higher Check design condition, try to avoid saturated air recirculation.
Motor Not Working Improper power supply Consult supply terminals.
Phase supply improper Check phase power, consult power supply terminal
Starter not performing properly Replaces starter, connect phase failure safety devices.
Motor winding damaged Send out for repair with specific explanation as per motor quality
Bearing jammed Clean / Replace Bearing
Fluctuating water flow observed Nozzles clogged Clean nozzles
Pump performing at higher / lower discharge pressure Check pump graph, check pump power, remove air trap, replace pump
Sump water level low Makeup sufficient water in basin
Valves, pump baffles, filters chocked Perform cleaning activity
Water carry away from top of Tower Water flow more than design parameter Put the correct pump
Nozzles clogged, not in position Clean nozzles, put in correct direction
Fills Chocked Clean / replace fills
Motor RPM higher Put the correct motor with comparatively lower RPM
Air flow not sufficient Fills clogged Clean / replace fills
Fan angle of attack is not correct Increase fan angle
Fan speed not correct Check motor power supply voltage, bearing condition
Excess vibration & noise through fan Fan not in good condition Replace / repair fan
Balancing not done Do static & dynamic balancing of fan
Motor not performing in good condition Check motor bearing
Motor mounting frame not in good condition Put a good motor support frame
Fan touching casing Create proper clearance between fan tip & casing