Greenheck Fan Greenheck Tamper-resistant Centrifugal Roof Exhaust NYD - Manual (Page 5)

5 Models NYD & NYB • Tamper-Resistant Centrifugal Roof Exhaust Fans
®
IMPORTANT
Adjust (tighten) belt tension after the first
24-48 hours of operation.
WARNING
Always disconnect, lock and tag power source
before servicing. Failure to disconnect power
source can result in fire, shock or serious injury.
CAUTION
Uneven cleaning of the wheel will produce an out
of balance condition that will cause vibration in the
fan.
WARNING
This unit should be made non-functional when
cleaning the wheel or housing (fuses removed,
disconnect locked off).
Maintenance: NYD/NYB
A proper maintenance program will help these units
deliver years of dependable service. Installation and
maintenance are to be performed only by qualified
personnel who are familiar with local codes and
regulations and who are experienced with this type
of equipment.
Motor maintenance is generally limited to cleaning
and lubrication (where applicable). Cleaning should
be limited to exterior surfaces only. Removing dust
buildup on motor housing ensures proper motor
cooling.
Greasing of motors is only intended when fittings
are provided. Many fractional horsepower motors
are permanently lubricated and should not be
lubricated after installation. Motors supplied with
grease fittings should be greased in accordance
with manufacturers’ recommendations. Where
motor temperatures do not exceed 104ºF (40ºC),
the grease should be replaced after 2,000 hours of
running time as a general rule.
Direct drive units require little maintenance except
for cleaning wheel, alignment and oiling according
to motor label instructions.
The unit should be made non-functional when
cleaning the wheel or housing (fuses removed,
disconnect locked off, etc.).
Wheels require very little attention when moving
clean air. Occasionally, oil and dust may accumulate
causing imbalance. When this occurs the wheel and
housing should be cleaned to ensure smooth and
safe operation.
All fasteners should be checked for tightness each
time maintenance checks are performed prior to
restarting unit.
A proper maintenance program will help these units
deliver years of dependable service.
Belt/Bearing Maintenance NYB Unit
1. Belts tend to stretch after a period of time. They
should be checked periodically for wear and
tightness. When replacing belts, use the same
type as supplied with the unit.
2. Matched belts should always be used on units
with multi-groove pulleys.
3. For belt replacement, loosen the tensioning
device enough to allow removal of the belt by
hand. Do not force the belts on or off. This may
cause cords to break, leading to premature
failure.
4. Once installed, adjust belts as shown in
“Pre-Starting Checks.”
5. Shaft bearings can be classified in two groups:
relubricating and non-relubricating. All bearings
are factory lubricated and require no further
lubrication under normal use (between -20ºF and
180ºF in a relatively clean environment).
6. Units installed in hot, humid or dirty locations
should be equipped with special bearings.
These bearings will require frequent lubrication.
7. On NYB belt driven fans, the standard cast
pillow block bearings are factory lubricated
and are provided with external grease fittings.
Annual lubrication is recommended, or more
frequently if needed, see Table 2. Do not over-
grease. Use only one or two shots of lubricant
with a hand gun. Maximum hand gun rating
is 40 psi. Rotate bearings during lubrication
where good safety practice permits. Caution
should be employed to prevent over packing or
contamination.
7. Grease fittings should be wiped clean. The unit
should be in operation while lubricating. Extreme
care should be used around moving parts.
8. Grease should be pumped in very slowly until a
slight bead forms around the seal. A high grade
lithium base grease should be used.
9. To ensure tightness, check pulley setscrews.
Proper keys must be in keyways.
10. Fan RPM should not be readjusted. Only use
pulleys of identical size and type when replacing
pulleys.
11. During the first few months of operation check
bearing setscrews periodically to ensure
tightness.
12. If unit is to be left idle for an extended period,
remove belts and store in a cool, dry place to
avoid premature belt failure.