Fig. 23 — Fan Rotation
Fan Pulley Alignment — Align as follows:
1.Loosen setscrews on pulleys.
2.Align pulleys visually and tighten setscrews on fan pulley to lock it in place.
3.Use the methods shown in Fig. 24 to check proper pulley alignment.
4.If pulleys are not in correct alignment, loosen the motor holddown bolts and slide the motor axially until the pulleys are aligned.
5.Tighten motor holddown bolts.
Pulley and Drive Adjustment — To obtain desired fan speed, refer to the fan motor and drive data in Tables
1.Remove belt from fan motor pulley after loosening motor from motor base.
2.Loosen setscrew in moveable flange of pulley. Screw moveable flange toward fixed flange to increase the fan speed and away from fixed flange to reduce speed. Before tightening setscrew, make certain that setscrew is over nearest flat surface of pulley hub (Fig. 24).
UNIT OPERATION HAZARD
Failure to follow this caution could cause equipment damage.
Increasing fan speed produces a greater load on motor. Do not exceed rated capacity of motor.
Condensate Drains — Keep condensate drains free of dirt and foreign matter.
Chilled Water Coil Freeze Protection — Shut off water supply to unit. Remove side panel of unit and remove vent and drain plugs in top and bottom of coil header. Drain coil and blow out remaining water. Reinstall plugs and side panel.
Fig. 24 — Fan Pulley Adjustments
Alternative freeze protection methods follow:
•Circulate hot water within the water coil’s supply main or supplementary space heating.
•Close off supply lines to unit and open a union or field- supplied drain valve in the return line.
IMPORTANT: Draining from return line will not com- pletely drain water from coils.
•After draining as much water as possible from coils, add sufficient antifreeze to prevent residual water in the coil from freezing.
•Add a sufficient quantity of
Coil Removal — Remove unit panels and corner posts as required. Disconnect coil connections and remove fastening screws. Remove coil through end or side sections of unit.
Cleaning Cooling Coil — Remove
Cleaning Insulation — The insulation contains an im- mobilized antimicrobial agent that helps prevent the growth of bacteria and fungi. Clean the inner surface of the insulation according to the separate maintenance instructions shipped with the unit.
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