Reznor B5SM Unit Installation Manual - Manual (Page 8)

8
stArtuP & ADjustMEnts
Pre-start Check List
Prior to start-up, complete the following inspection:
√ Verify the unit is level and condensate can drain. Check
condensate drain line(s) for proper slope and trap.
√ Verify the air handler is mounted securely.
√ Verify the surrounding area and top of the unit is free
from obstructions and debris.
√ Check all ductwork connections. Make sure the duct
work is adequetly sealed to prevent air leakage.
√ Check all coil connections for leaks.
√ Verify that the line voltage power leads are securely
connected and the unit is properly grounded.
√ Verify that the low voltage wires are securely connected
to the correct leads on the low voltage terminal strip.
Make sure the thermostat is wired correctly.
√ Verify the blower rotates properly. Check the blower belt
between the pulleys for proper tension and alignment.
√ Verify the power supply branch circuit overcurrent
protection is sized properly.
√ Verify all filters are in place and all equipment access/
control panels are in place
Blower rotation - 3 phase units only
If blower is turning opposite of arrow direction, disconnect
all power to unit and allow all rotating equipment to stop,
then interchange any two field wired leads at the terminal
block OR disconnect connections.
Blower speed Adjustment
The blower speed has been preset at the factory. For
optimum system performance and comfort, it may be
necessary to change the factory set speed. Please refer
to the Blower Performance Data section (page12).
notE: Adjustment of the blower speed is made through
varying the pitch of the motor sheave. This adjustment
allows for a wide range of installation applications. Do
not adjust a sheave to a setting not shown in the tables.
Grounding
WArnInG:
the unit cabinet must have an uninterrupted
or unbroken electrical ground to minimize
personal injury if an electrical fault should occur.
Do not use gas piping as an electrical ground!
This unit must be electrically grounded in accordance
with local codes or, in the absence of local codes, with
the National Electrical Code (ANSI/NFPA 70) or the CSA
C22.1 Electrical Code. Use the grounding lug provided in
the control box for grounding the unit.
Motor sheave Adjustment
The motor sheave consists of an outer, moveable pulley
face and an inner stationary face. To adjust the motor
sheave,
1. Relieve the belt pressure by loosening motor mount
bolts and the belt tensioning bolts on the motor mount.
2. Move the blower fan belt out of the way (if necessary)
and loosen the set screw in the outer sheave face.
3. Rotate the face in increments of one half or full turns
only. notE: This maintains the set screw position
precisely over the flats on the pulley hub. Rotating the
sheave clockwise (when viewed from the lead end of
motor - opposit end of shaft) will make the blower run
slower which decreases airflow. Rotating the sheave
counter clockwise (as viewed from lead end) will cause
the blower to speed up.
4. Tighten the setscrews after the desired adjustment has
been made and verify the moveable face is properly
secured.
V-Belt Alignment & tensioning
IMPortAnt! Belt alignment is extremely critical for
proper operation and life expectancy of belts and
motor bearings. If not equipped with proper alignment
tools, prior to removal of blower and motor pulley,
measure center of each pulley to a reference point
for replacement of new pulleys.
After installing the blower pulley onto the blower shaft,
use an in-groove belt alignment tool to verify the parallel
offset of the sheave and pulley. If a laser alignment tool
is unavailable, place a straight edge, piano wire, or string
in the center of the adjustable sheave and pulley V-notch
to adjust parallel offset alignments.
notE: The straight edge, piano wire or string should be
close to the center of the groove and contact each sheave
in two places (see Figure 6). The objective is to have the
center lines of the two sheaves in line. Belt drives should
be aligned as perfect as possible to maximize drive life.
Calculate or measure the belt span length as shown in
Figures 7 & 8 (page 9). Calculate the required deflection
by multiplying this number by 1/64. For example, if the
belt span is 32 inches, 32 x 1/64 = 1/2 inch deflection.
notE: Excessively high or low tensions will affect belt
life. Check belt tensions again after 24 hours of operation.
Keep extra belts stored in a cool, dark, dry place.
The belt tension is controlled utilizing the adjustable motor
mounting plate. To release the belt tension, first loosen
the 4 motor mounting nuts that attach the motor to the
mounting plate approximately ½-1 turn and then use
the adjusting bolt to release the belt tension. To tighten,
complete the steps in the reverse order.
The amount of phase imbalance (1.32%) is satisfactory
since the amount is lower than the maximum allowable
2%. Please contact your local electric utility company if
your voltage imbalance is more than 2%.