Greenheck LD/LDP/LB/LBP (453283) - Manual (Page 5)

Centrifugal Roof Exhaust Fans 5
®
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
far enough to allow removal of the belt by hand. Do
not force belts on or off. This may cause cords to
break, leading to premature belt 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 (-29° to
82°C) 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. Caution should be
employed to prevent overpacking 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 is recommended.
9. Direct drive units require little maintenance except
for cleaning, wheel alignment, and oiling according
to motor label instructions.
IMPORTANT
Adjust (tighten) belt tension after the first 24-48 hours
of operation.
Belt Span 64
Deflection =
Belt Span
Figure 6
WARNING
Always disconnect, lock and tag power source before
servicing. Failure to disconnect power source can
result in fire, shock or serious injury.
AVERTISSEMENT
Pour écarter les risques d’incendie, de choc électrique
ou de blessure grave, veiller à toujours débrancher,
verrouiller et étiqueter la source de courant avant
l’entretien.
IMPORTANT
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).
AVERTISSEMENT
L’appareil doit être rendu non opérationnel lors du
nettoyage de la turbine ou du caisson (fusibles retirés,
sectionneur verrouillé).
10. The adjustable motor pulley is factory set for the
RPM specified. Speed can be increased by closing
or decreased by opening the adjustable motor
sheave.
11. Two groove variable pitch pulleys must be adjusted
an equal number of turns open or closed.
12. Any increase in speed represents a substantial
increase in the horsepower required by a unit.
13. Motor amperage should always be checked to
avoid serious damage to the motor when speed is
varied.
Maintenance
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 hp motors are permanently
lubricated and should not be lubricated further. 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 2000 hours of
running time as a general rule.
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