Installation

Warning

Caution

Note

necessary, correct the alignment. See the Maintenance section for belt tensioning and sheave alignment—page 22.

Improper installation of the fan guard will destroy the structural in- tegrity of the fan guard. It is essential that the fan guard be installed in accordance with the Field Installation Manual shipped with the tower. Do not force the fan cylinder out of round.

3.Momentarily energize (“bump”) the motor and observe rotation of the fan. The fan should rotate in a counterclockwise direction when viewed from below. If rotation is backwards, shut off the fan and reverse two of the three primary leads supplying power to the motor.

If tower is equipped with a two-speed motor, check for proper rota- tion at both speeds. Check also to see that starter is equipped with a 20 second time delay which prevents direct switching from high speed to low speed. If the fan is intended to be reversed for deicing purposes, make sure that the starter is equipped with a 2 minute time delay between changes of direction. These delays will prevent abnormal stress from being applied to the mechanical equipment and the electrical circuit components.

4.Run the motor and observe the operation of the mechanical equip- ment. Operation should be stable.

5.After the first 30 minute run check motor AMPS and voltage with full water and heat load. Repitch fan, if necessary—correct for low ambi- ent temperatures. Refer to motor manual.

6.After 10 to 60 hours of operation check the torque on the fan and motor sheave bushings and check belt tension. Refer to the Main- tenance section of this manual for torque values and belt tensioning instructions—page 22.

If the water supply system is not being operated—or if there is no heat load on the system—motor amps read at this time may indicate an apparent overload of as much as 10–20%. This is because of the increased density of unheated air flowing through the fan. Determi- nation of an accurate motor load should await the application of the design heat load.