Greenheck DGX Installation, Operation And Maintenance Manual page 38

Lock-out the gas and the electrical power to the unit before performing any maintenance or service
V-Belt Drives
V-belt drives must be checked on a regular basis for
wear, tension, alignment and dirt accumulation.
Check the tension by measuring the deflection in the
belt as shown in figure #62.
Check the alignment by using a straight edge across
both sheaves as shown in figure #63.
IMPORTANT!
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.
Figure 62. Belt tension
Maintenance - Routine
CAUTION!
operations to this unit.
IMPORTANT!
When replacing V-belts on
multiple groove drives all belts
should be changed to provide
uniform drive loading.
B elt S pan
D eflection =
64
B elt S pan
IMPORTANT!
Premature or frequent belt failures can be caused by
improper belt tension, 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.
Do not install new belts on worn
sheaves. If the sheaves have
grooves worn in them, they must
be replaced before new belts are
Figure 63. Drive Alignment
38
Abnormally low belt tension
will cause squealing on
start-up, excessive belt
flutter, slippage and
overheated sheaves
IMPORTANT!
installed.