KAH Operation & Maintenance Guide
Page: 7 of 88
Krueger | 1401 N Plano Rd | Richardson, TX 75081 | 972.680.9136 | kruegerinfo@krueger-hvac.com | www.krueger-hvac.com
Inspecting Belts and Sheaves
1. Verify that the sheaves are properly aligned and tight
on the shaft. Improper sheave alignment and belt
tension are potential causes of excessive noise and
vibration, and shortened belt and bearing life. Refer
to SECTION 3 - MAINTENANCE in this manual for
more information.
2. Check the belt tension. If not familiar with the process,
refer to SECTION 3 - MAINTENANCE in this manual.
It is normal for belts to loosen after start-up. The new
belts will run in or take a set by seating slightly deeper
into the grooves of the sheaves. Recheck the tension
after one day, and three days.
3. Make sure the motor mounting bolts and adjustable
motor base bolts are tight.
Checking Isolators
Check the fan base isolators and thrust restraints for
proper adjustment.
•
Standard fan isolation consists of spring isolators as
shown in Figure 3 (right) mounted under the internal
fan assembly.
•
For thrust restraint adjustment procedures, if
applicable, refer to the service manual.
•
Prepare the fan isolators for operation, using the
following instructions:
1. After removing the tie down bolts from the
internal fan assembly, check the blower/motor
frame for the correct height, and that the frame
is level.
2. To adjust the isolators as shown in Figure 3
(right).
a. Loosen the cap screws on top of the
adjustment bolt.
b. Turn the adjusting bolt.
c. Check the operational height and level of
the frame. Repeat this procedure until the
height and frame are level.
d. Tighten the cap screws. Refer to the
service manual for additional instructions.
•
Verify the fan is aligned with the AHU discharge.
•
Readjust the isolators as necessary.
SECTION 2 - START-UP & OPERATION (CONTINUED)
FIGURE 2 - FAN & MOTOR ISOLATOR SUPPORT FRAME
Tie Down Bolts
FIGURE 3 - SPRING ISOLATOR
SETSCREW
DIAMETER
(IN)
HEX SIZE
ACROSS
FLATS (IN)
MINIMUM
RECOMMENDED TORQUE
IN LB
FT LB
1/4
1/8
66 - 85
5.5 - 7.08
5/16
5/32
126 - 164
10.5 - 13.7
3/8
3/16
228 - 296
19.0 - 24.7
7/16
7/32
348 - 452
29.0 - 35.7
1/2
1/4
504 - 655
42.0 - 54.6
5/8
5/16
1104 - 1435
92.0 - 119.6
TABLE 1 - TORQUE FOR TIGHTENING SET SCREWS
