ECH EVAPORATIVE CONDENSERS
MAINTENANCE
140.910-IOM (DEC 13)
Page 14
Inspection and Maintenance:
•
These drives require a periodic check of the belt
condition and, when necessary, tension adjustment. The
recommended service intervals are as follows:
1. Initial Start-up: Servicing is not required prior to initial
unit start-up. The drive has been tensioned and aligned
at the factory.
2. Seasonal Start-up: Readjust the belt tension.
3. Operation: After the first 24 hours of operation,
readjust the belt tension on a new unit start-up or
installation of a new belt. Thereafter, check the belt
condition monthly, and adjust tension as necessary.
Readjust tension at least once every 3 months.
Figure 12a - Belt Tension
Figure 12b - Belt Tension
•
Belt tension check:
1. Place a straight edge along the belt from sheave to
sheave as shown in Figure 12a, or use a tape measure
as shown in Figure 12b, to measure belt deflection.
2. Apply a moderate force by hand (approximately 40
lb/18.1 kg) evenly across the width of the belt in the
center of the span between the sheaves.
3.
There is adequate belt tension if the belt deflects be-
tween 1/4” and 3/8” as shown in Figures 12a and 12b.
•
Belt tension adjustment (if required):
1. Loosen the lock nut on the motor base adjusting screw.
2. Turn the motor base adjusting screw clockwise to
tension the belt, or counterclockwise to relieve belt
tension. During adjustment of belt tension, rotate the
drives several times by hand to evenly distribute the
tension throughout the belt.
•
When the belt is properly tensioned, retighten the locking
nut on the motor base adjusting screw.
NOTICE
There should be no “chirp” or “squeal” when the fan mo-
tor is started.
Alignment:
•
Check the drive alignment annually to ensure maximum
belt life.
•
Drive alignment check and adjustment:
1. Place a straight edge across the driver and the driven
sheaves as shown in Figure 13a for standard drives
and in Figure 13b for the Sentinel™ Fan System or the
Sentinel PLUS™ Fan System.
2. The straight edge should contact all four points as
shown in Figure 13a indicating proper drive alignment.
3. There should be no more than 1/16” deviation from
four points of contact.
4. In case of realignment, loosen the motor sheave and
align it with the fan sheave. Allow 1/4” for draw-up as
the bushing screw is retightened.
Figure 13a - Standard Drive Alignment
Figure 11 - Fan System (Optional Sentinel™ configuration)
