Greenheck PVe (472846) - Manual (Page 20)

20 Model PVe Heat Recovery Unit
Fan Motors
Motor maintenance is generally limited to cleaning
and lubrication. Cleaning should be limited to exterior
surfaces only. Removing
dust and grease buildup
on the motor housing
assists proper motor
cooling. Never wash-
down motor with high
pressure spray. Greasing
of motors is only intended
when fittings are provided.
Many fractional motors
are permanently lubricated for life and require no further
lubrication.
Fan Wheel & Fasteners
Wheels require very little attention when moving clean
air. Occasionally oil and dust may accumulate on the
wheel causing imbalance. When this occurs the wheel
and housing should be cleaned to assure smooth and
safe operation. Inspect fan impeller and housing for
fatigue, corrosion or wear.
Routinely check all fasteners, set screws and locking
collars on the fan, bearings, drive, motor base and
accessories for tightness. A proper maintenance
program will help preserve the performance and
reliability designed into the fan.
Bearings
Most bearings are permanently lubricated and require
no further lubrication under normal use. Normal use
being considered -20º to 120ºF and in a relatively
clean environment. Some bearings are relubricatable
and will need to be regreased depending on fan use.
Check your bearings for grease zerk fittings to find
out what type of bearing you have. If your fan is not
being operated under normal use, bearings should be
checked monthly for lubrication.
Maintenance Procedures
Lubrication
Check all moving components for proper lubrication.
Apply lubrication where required. Any components
showing excessive wear should be replaced to maintain
the integrity of the unit and ensure proper operation.
Dampers
Check all dampers to ensure they open and close
properly and without binding. Backdraft dampers can
be checked by hand to determine if blades open and
close freely. Apply power to motorized dampers to
ensure the actuator opens and closes the damper as
designed.
Fan Belts
Belts must be checked on a regular basis for wear,
tension, alignment, and dirt accumulation. Premature
or frequent belt failures can be caused by improper
belt tension (either too loose or too tight) or misaligned
sheaves. Abnormally high belt tension or drive
misalignment will cause excessive bearing loads and
may result in failure of the fan and/or motor bearings.
Conversely, loose belts will cause squealing on start-
up, excessive belt flutter, slippage, and overheated
sheaves. Both loose and tight belts can cause fan
vibration.
When replacing belts on multiple groove drives, all belts
should be changed to provide uniform drive loading. Do
not pry belts on or off the sheave. Loosen belt tension
until belts can be removed by simply lifting the belts off
the sheaves. After replacing belts, insure that slack in
each belt is on the same side of the drive. Belt dressing
should never be used.
Do not install new belts on worn sheaves. If the
sheaves have grooves worn in them, they must be
replaced before new belts are installed.
The proper belt setting is
the lowest tension at which
the belts will not slip under
peak load operation. For
initial tensioning, set the belt
deflection at 1/64-inch for each
inch of belt span (measured halfway between sheave
centers). For example, if the belt span is 64 inches,
the belt deflection should be one inch (using moderate
thumb pressure at mid-point of the drive). Check belt
tension two times during the first 24 hours of operation
and periodically thereafter.
Belt Span
Deflection =
Belt Span
64
WARNING
REFER TO GENERAL SAFETY INFORMATION
Do not operate this unit without the filters and
birdscreen installed. They prevent the entry of foreign
objects such as leaves, birds, etc.
Do not remove access panels or other unit
components while standing on a ladder or other
unsteady base. Access panels and unit components
are heavy and serious injury may occur.