COOK AC - Manual (Page 4)

4
Fan Bearings
NOTICE! The fan bearings are provided
prelubricated. Any specialized lubrication instructions
on fan labels supersedes information provided herein.
Bearing grease is a petroleum lubricant in a lithium
base conforming to a NLGI #2 consistency. If user
desires to utilize another type of lubricant, they take
responsibility for flushing bearings and lines, and
maintaining a lubricant that is compatible with the
installation.
A NLGI #2 grease is a light viscosity, low-torque, rust-
inhibiting lubricant that is water resistant. Its temperature
range is from -30°F to 200°F and capable of intermittent
highs of 250°F.
Bearings should be relubricated in accordance with the
condition chart below.
For best results, lubricate the bearing while the fan is in
operation. Pump grease in slowly until a slight bead forms
around the bearing seals. Excessive grease can damage
seal and reduce life through excess contamination and/or
loss of lubricant.
In the event that the bearing cannot be seen, use no
more than three injections with a hand operated grease
gun.
Motor Bearings
Motors are provided with prelubricated bearings. Any
lubrication instructions shown on the motor nameplate
supersede instructions below.
Direct Drive 1050/1075,1200,1300 &1500 rpm units use a
prelubricated sleeve bearing that has a oil saturated
wicking material surrounding it. The initial factory lubrication
is adequate for up to 10 years of operation under normal
conditions. However, it is advisable to add lubricant after 3
years. Use only LIGHT grade mineral oil or SAE 10W oil up
to 30 drops. If the unit has been stored for a year or more it
is advisable to lubricate as directed above. For units in
severe conditions, lubrication intervals should be reduced
to half.
Motors without sleeve bearings (as described above) will
have grease lubricated ball or roller bearings. Motor
bearings without provisions for relubrication will operate up
to 10 years under normal conditions with no maintenance.
In severe applications, high temperatures or excessive
contaminates, it is advisable to have the maintenance
department disassemble and lubricate the bearings after 3
years of operation to prevent interruption of service.
Conditions Chart
For moist or otherwise contaminated installations; divide the interval by a
factor of 3. For vertical shaft installations divide the interval by a factor of 2.
RPM Temp °F Greasing Interval
Up to 1000
-30 to 120 6 months
120 to 200 2 months
1000 to 3000
-30 to 120 3 months
120 to 200 1 month
Over 3000
-30 to 120 1 month
120 to 200 2 weeks
Any Speed < -30 Consult Factory
Any Speed > 200 1 week
For motors with provisions for relubrication, follow
intervals of the table below.
NOTICE! Motors are provided with a polyurea mineral
oil NGLI #2 grease. All additions to the motor bearings
are to be with a compatible grease such as Exxon Mobil
Polyrex EM and Chevron SRI.
The above intervals should be reduced to half for vertical
shaft installations.
Motor Services
Should the motor prove defective within a one-year period,
contact your local Loren Cook representative or your nearest
authorized electric motor service representative.
Changing Shaft Speed
All belt driven ventilators (5HP or less) are equipped with
variable pitch pulleys. To change fan speed, perform the
following:
1. Loosen setscrew on driver (motor) pulley and remove
key, if equipped.
2. Turn the pulley rim to open or close the groove facing. If
the pulley has multiple grooves, all must be adjusted to
the same width.
3. After adjustment, inspect for proper belt tension.
Speed Reduction:
Open the pulley in order that the belt rides deeper in the
groove (smaller pitch diameter).
Speed Increase:
Close the pulley in order that the belt rides higher in the
groove (larger pitch diameter). Ensure that the RPM limits of
the fan and the horsepower limits of the motor are
maintained.
Relubrication Intervals
Service
Conditions
NEMA Frame Size
Up to and
including 184T
213T-365T 404T and larger
1800 RPM
and less
Over 1800
RPM
1800 RPM
and less
Over 1800
RPM
1800 RPM
and less
Over 1800
RPM
Standard 3 yrs. 6 months 2 yrs. 6 months 1 yr. 3 months
Severe 1 yr. 3 months 1 yr. 3 months 6 months 1 months
Maximum RPM with standard or reenforced wheel
Size
ACE-B ACRU-B &
ACW-B
ACRU-HP &
ACW-HP
ACRU-XP
&
ACW-XP Standard Reinforced Standard Reinforced Standard Reinforced
60 1981 -
70 1941 -
80 1806 -
100 2013 - 2002 -
120 1669 - 1671 -
135 1574 - 1574 -
150 1519 - 1520 - 1952 -
165 1296 - 1295 - 1728 - 2508
180 1513 - 1546 - 1829 - 2396
195 1348 - 1353 - 1570 - 2100
210 1190 - 1197 - 1626 - 2126
225 1043 - 1086 - 1435 - 1879
245 885 - 901 - 1185 1234 1616
270 752 - 766 - 1025 1049 1656
300 837 861 837 877 980 1046 1391
330 716 734 716 748 830 912 1182
365 624 648 624 659 735 872 1132
402 539 550 539 560
445 463 465 463 473
490 360 396 360 403
540 347 401 -