Fan System; Fan Motor Bearings; Fan Shaft Ball Bearings - EVAPCO ATC-E Operation And Maintenance Instruction

Operation and Maintenance Instructions
System/Condensing Temperature Drops
Decrease the fan speed, as required.
System Off / No Load
The system pump turns off. The starter interlock will energize any optional basin heaters in cold weather.
The recirculation pump should not be used as a means of capacity control, and should not be cycled frequently. Excessive cycling
can lead to scale build-up, and reduce wet and dry performance.
Dry Operation
During colder winter months it is possible to turn off the spray pump, drain the cold water basin, and just cycle the fans. Be sure to
leave the basin drain open during this time to prevent collection of rain water, snow, etc. If the unit has positive closure dampers
they should be fully opened before the fans turn on. If this method will be used on a centrifugal fan, forced draft unit, be sure to
verify that the motor and drives have been properly sized to handle the reduction in static pressure experienced when the spray
water is turned off.
NOTE: MINIMUM CONTROL POINT FOR PROCESS FLUID SHOULD NEVER BE LOWER THAN 42º F.
NOTE: WHEN A UNIT IS PROVIDED WITH A DISCHARGE DAMPER ASSEMBLY, THE CONTROL SEQUENCE SHOULD
CYCLE THE DAMPERS OPEN AND CLOSED ONCE A DAY REGARDLESS OF CAPACITY REQUIRMENTS TO PREVENT
THE ASSEMBLY FROM SEIZING. THE FAN MOTOR SHOULD BE SHUT OFF WHENEVER THE DAMPERS ARE CLOSED.

Fan System

The fan systems of both centrifugal and axial driven units are rugged; however, the fan system must be checked regularly and
lubricated at the proper intervals. The following maintenance schedule is recommended.

Fan Motor Bearings

EVAPCO evaporative cooling units use either a T.E.A.O. (Totally Enclosed Air Over) or a T.E.F.C. (Totally Enclosed Fan Cooled) fan
motor. These motors are built to "Cooling Tower Duty" specifications. They are supplied with permanently lubricated bearings and
special moisture protection on the bearings, shaft and windings. After extended shut-downs, the motor should be checked with an
insulation tester prior to restarting the motor.

Fan Shaft Ball Bearings

For induced draft units, lubricate the fan shaft bearings every 1,000 hours of operation or every three months. For forced draft
units, lubricate the fan shaft bearings every 2,000 hours of operation or every six months. Use any of the following synthetic
waterproof, polyurea inhibited greases which are suitable for operation between -20°F and 350°F. (For colder operating
temperatures, contact the factory).
Mobil – Polyrex EM Chevron - SRI Timken Pillowblock Grease
Feed grease slowly into the bearings or the seals may be damaged. A hand grease gun is recommended for this process.
When introducing new grease, all grease should be purged from the bearings.
Most EVAPCO units are supplied with extended grease lines to allow easy lubrication of the fan shaft bearings as shown in Table 1.
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