Greenheck G/GB (471558) - Manual (Page 10)

Downblast Centrifugal Roof Exhaust 10
®
Recommended Bearings Lubrication
Frequency in Months
NOTE: If unusual environment conditions exist
(extreme temperature, moisture or contaminants)
more frequent lubrication is required.
A good quality lithium base grease, conforming to
NLGI Grade 2 consistency, such as those listed in
Table 3 may be used.
Table 3: Grease Manufacturers
Manufacturer Grease (NLGI #2)
U.S. Electric Motors Grease No. 83343
Chevron U.S.A. Inc Chevron SRI Grease #2
Mobil Oil Corporation
Mobilith
Mobil 532
Texaco, Inc.
Premium BRB #2
Texaco Multifak #2
Amoco Oil Co. Rykon Premium #2
Exxon Unirex N2
Shell B Shell Alvania #2
Table 2: Suggested Fan Bearing Lubrication Intervals
Interval
(months)
Type of Service
1 to 3
Heavy duty in dirty, dusty locations; high ambient
temperatures; moisture laden atmosphere; vibration.
3 to 6
12 to 24 hours per day, heavy duty, or if moisture is
present
6 to 12
8 to 16 hours per day in clean, relatively dry
atmosphere
12 to 18 Infrequent operation or light duty in clean atmosphere
Poor Poor
Dampers must open fully.
Use motorized dampers in
low airflow applications to
reduce losses. Avoid sharp turns or
entrance conditions which
cause uneven flow. Use
turning vanes in elbows to
reduce adverse effects.
Good
Good
Provide uniform airflow at
fan inlet to assure optimum
performance. Provide uniform airflow at
fan inlet and through the
damper to assure optimum
performance. The curb
cap should be three wheel
diameters from the radius.
Use turning vanes in duct
when possible.
Fan Inlet Connections
In order to assure proper fan performance, caution
must be exercised in fan placement and connection
to the ventilation system. Obstructions, transitions,
poorly designed elbows, improperly selected
dampers, etc., can cause reduced performance,
excessive noise and increased mechanical stress.
For performance to be as published, the system must
provide uniform and stable airflow into the fan.