Mammoth V-Cube - Manual (Page 18)

Dampers
Units from Venmar CES may or may not incorporate the
use of dampers. If dampers are present within the unit,
the following maintenance should occur in order to pre-
vent the unit from working under too much pressure and
to prevent any other issues.
Dampers must be kept free of foreign matter that might
impede normal free movement. Bearings between blades
and frames are made of polymer and require no mainte-
nance. Note that the damper shafts do not need lubrica-
tion. All Venmar CES dampers and linkages are assembled
with non lubricating bearings.
• Attachment mechanism linking motors to dampers
should be checked for tightness.
• Damper jackshafts (if provided) are fitted with grease
nipples and should be lubricated once a year. Use a
premium quality lithium based grease conforming
to NLGI Grade 2 or 3 (examples are: Mobil Mobilith
AW2, Chevron Amolith #2, Texaco Premium RB or
Shell Alvania #2).
• Dampers should be inspected for dirt; check the
shaft, arms, bars and controls rod every three
months.
• Inspect the seals to ensure none have pulled loose or
deteriorated. If a seal has been damaged, repair or
replace it with the same seal or same seal material.
Contact Venmar CES for replacement parts.
Belt.Driven.Fans
Belt driven fan, motor and drive assemblies should be
checked and inspected at regular intervals per the inspec-
tion list and procedures below. Listen for vibrations or
unusual sounds. Severe damage, premature failure and
loss of airflow can be avoided by regular inspection and
maintenance.
1. Check the fan, motor and bearing mounting bolts for
tightness according to the bolt torque chart in Table
1 below at time of start-up, after 24 hours, then
every three months.
2. Check the fan wheel hub, bearings and drive sheave
set screws for tightness according to the set screw
torque chart in Table 2 below at time of start-up,
after 24 hours of operation, monthly for the initial
three months then every three months thereafter.
If wheel or bearing set screws have worked loose,
check the wheel for any signs of movement (inlet
space clearance between the fan wheel and housing)
or loose blades. If Loctite was used on any set screws
that have come loose, the set screws must be re-
moved and cleaned before re-tightening and Loctite
must be re-applied.
!
WARNING
Many of the following steps need to be performed with
the unit powered off and locked out. Disconnect the
main power switch to the unit before performing service
and maintenance procedures.
Table 1: Minimum head bolt torque in lb-ft (Grade 5 bolts)
Size (Inches) Thread Designation Minimum Torque
1/4 –20
1/4–28
5/16–18
5/16–24
3/8–16
UNC
UNF
UNC
UNF
UNC
6
7
14
16
24
3/8–24
7/16–14
7/16–20
1/2–13
1/2–20
UNF
UNC
UNF
UNC
UNF
28
42
45
69
83
9/16–12
9/16–18
5/8–11
5/8–18
3/4–10
UNC
UNF
UNC
UNF
UNC
99
118
150
176
254
3/4–16
7/8–9
7/8–14
1–8
1–14
UNF
UNC
UNF
UNC
UNF
301
358
422
500
602
Soft metric conversions are not acceptable for screw and hex sizes.
Table 2: Wheel set screw torque in lb-ft
Set Screw Size
Diameter (Inches)
Carbon Steel Set Screw Torque*
lb-in lb-ft
1/4 75 6.2
5/16 144 12.0
3/8 252 21.0
7/16 396 33.0
1/2 600 50.0
5/8 1,164 97.0
3/4 2,016 168.0
7/8 3,204 267.0
1 4,800 400.0
*Stainless steel set screws are not hardened and should not be
tightened to more than half the values shown.
VCES-V-CUBE-IOM-1A 18