COOK QMX - Manual (Page 2)

2
Correct
Incorrect
MIN
3 DIA
duct diameter of straight duct before placing an elbow or
damper. Clearance is also required on the inlet and outlet
for maintenance such as pulley or bearing replacement.
Non-Ducted Inlet Clearance
If your fan has an open inlet (no duct work), the fan must
be placed 1 effective wheel diameter away from walls and
bulkheads.
Free Discharge
Avoid a free discharge into the plenum. This will result in
lost efficiency because it doesn’t allow for a static regain.
Inlet Duct Turns
For ducted inlets, allow at least 3 effective wheel diame-
ters between duct turns or elbows and the fan inlet.
Discharge Duct Turns
Where possible, allow 3 duct diameters between duct
turns or elbows and the fan outlet. Refer to the drawing
below.
Non-ducted Inlet Clearance
MIN
1 DIA
Free Discharge
Correct Incorrect
Correct
Incorrect
MIN
3 DIA
Inlet Duct Turns
d. Adjust the isolators by turning the leveling nut counter
clockwise several turns at a time alternately on each
isolator until the fan weight is transferred onto the iso-
lators and the fan raises uniformly off the blocks. Then
remove the blocks.
e. Turn lock nut onto leveling bolt and secure firmly in
place against the top of the mounting flange or frame.
f. Secure isolators to mounting surface.
Floor Mounted Rubber-In-Shear (RIS) Isolators
a. Mount fan on isolation base or rails (if supplied).
b. Elevate fan to provide room to insert isolators
between the fan and foundation and block in position.
c. Position isolators under fan and secure bolts.
d. Remove blocks and allow fan to rest on floor. Isolators
must be installed on a level surface (leveling should
not be required).
e. Secure isolators to mounting surface.
Ceiling Mounted Spring and Rubber-in-Shear (RIS) Iso-
lators
a. Elevate fan to operating height and brace.
b. Attach threaded rod to overhead support structure
directly above each mounting hole. Rod should extend
to within a few feet of fan.
c. Attach isolator to end of threaded rod using a nut on
each side of isolator bracket.
d. Insert another section of threaded rod through the fan
mounting hole and isolator.
e. Attach two nuts to threaded rod in isolator.
f. Place adjusting nut and locking nut on threaded rod
near fan mounting bracket.
g. Alternately rotate adjusting nut at each mounting loca-
tion until the fan weight is uniformly transferred to the
isolators. Remove bracing.
Duct and Damper Installation
Efficient fan performance relies on the proper installation
of inlet and discharge ducts, as well as dampers. Be sure
your fan conforms to the guidelines below and allows 3
Figure 1 -Floor Mount Isolators
Rubber-In-Shear Isolator Spring Isolator
Rubber-In-Shear Ceiling Isolators Ceiling Mounted Spring Isolator
Figure 2 - Ceiling Mount Isolators
Discharge Duct Turns