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Maintenance
Always disconnect power before working on or near a unit. Lock and tag the disconnect switch or breaker to
prevent accidental power up. Failure to comply with this safety precaution could result in serious injury or death.
Once the fan has been put into operation, a periodic maintenance program should be set up to preserve the
reliability and performance of the fan.
Items to be included in this program are:
• Fasteners and set screws
• Bearings
• Lubrication of bearings and motor
• Belts
• Removal of dust, dirt and debris
• Dampers for roof upblast configuration
Changing the belts or drives can significantly increase the amp draw of the motor. If changes are made to the
drives or belts, the amps must be checked to assure no overamping.
Fasteners and Set Screws - Normal fan vibration has a tendency to loosen mechanical fasteners. Periodic
inspection should include checking all fasteners, set screws, and locking collars attaching the propeller to the shaft
and the shaft to the bearings. Loose bearing set screws and locking collars will lead to premature failure of the fan
shaft.
Bearings on belt drive fans - Bearings are the most critical moving part of the fan and should be inspected at
periodic intervals. Locking collars and set screws, in addition to fasteners attaching the bearing to the bearing plate,
must be checked for tightness.
In a clean environment and temperature between 32° and 200°F (0 to 93°C), fan shaft bearings with grease fittings
should be lubricated semi-annually using a high quality lithium based grease. Bearings operating outside these
temperature parameters require special high or low temperature grease. If unusual environmental conditions exist,
such as temperatures below 32°F (0°C) and above 200°F (93°C), high moisture, or contaminants, more frequent
lubrication is required.
With the unit running, add grease very slowly with a manual grease gun. Be careful not to unseat the seal by over
lubricating or using excessive pressure. Bearings without grease fittings are lubricated for life.
Bearings are one of the most critical parts of a fan and should be inspected at regular intervals. Locking collars, set
screws and fasteners attaching the bearings to the fan should also be checked.
Model TBI fans are equipped with extended lubrication lines as standard. The grease fittings are located on the
exterior of the fan housing next to the motor cover and should be wiped clean before adding grease.
Motors - Motor maintenance is generally limited to cleaning and lubrication. Cleaning should be limited to exterior
surfaces only. Removing dust and grease build-up on the motor housing assists proper motor cooling.
Do not allow water or solvents to enter the motor or bearings. Under no circumstances should motors or bearings
be sprayed with steam, water or solvents.
Lubrication of motors is intended only when fittings are provided. Many fractional horsepower motors are
permanently lubricated for life and require no further lubrication. Motors supplied with grease fittings should be
greased in accordance with the manufacturer's directions on the motor nameplate.
Belts - Premature belt failures are frequently caused by improper belt tension (either
too loose or too tight), misaligned pulleys, or by prying belts on and off pulleys. The
proper tension for operating a V-belt is the lowest tension at which the belts will
not slip at peak load conditions. For initial tensioning, the proper belt deflection is
1/64-inch for each inch of belt span, measured half way between the pulley centers.
For example, if the belt span is 64 inches, the belt deflection should be one inch
using moderate thumb pressure at midpoint of the drive (Fig. 2).
Check belt tension two times during the first 24 hours of operation, after 100 hours of operation, and periodically
thereafter. To adjust belt tension, simply pivot the motor on the motor plate. Use the bolts in the slotted brackets and
adjustment rods with bolts as adjustment points until proper belt tension is attained.
8
Tubular Inline Fans
WARNING
IMPORTANT
IMPORTANT
Fig. 2
Deflection = Belt Span
64
Belt Span
C
®
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