Lennox ZCC Series Unit Information page 21

PULLEY ALIGNMENT
ALIGNED
MOTOR
BELT
PULLEY
NOT ALIGNED
FIGURE 7
F-Check Belt Tension
Over-tensioning belts shortens belt and bearing life.
Check belt tension as follows:
1 - Measure span length X. See figure 8.
2 - Apply perpendicular force to center of span (X) with
enough pressure to deflect belt 1/64" for every inch
of span length or 1.5mm per 100mm of span length.
Example: Deflection distance of a 40" span would be
40/64" or 5/8".
Example: Deflection distance of a 400mm span would
be 6mm.
Example: Deflection distance of a 400mm span would
be 6mm.
DRIVE
ADJUSTABLE SHEAVE
NO.
BROWNING NO.
1 1VP34x7/8
2 1VP40x7/8
3 1VP34x7/8
4 1VP44x7/8
5 1VP50x7/8
6 1VP50x7/8
10 1VP50x1-1/8
11 1VP50x1-1/8
12 1VP50x1-1/8
BLOWER
PULLEY
TABLE 2
MANUFACTURER'S NUMBERS
OEM PART NO. BROWNING NO.
31K6901 AK61x1
79J0301 AK59x1
31K6901 AK46x1
P-8-1488 AK74x1
P-8-2187 AK69x1
P-8-2187 AK64x1
P-8-1977 BK77x1
P-8-1977 BK67x1
P-8-1977 BK62x1
Page 21
3 - Measure belt deflection force. For a new 2 and 3hp
belt, the deflection force should be 5.0-7.0 lbs. (35-
48kPa). For a new 5hp belt, the deflection force
should be 7-10lbs. (48-69kPa).
A force below these values indicates an under-
tensioned belt. A force above these values indicates
an over-tensioned belt.
MEASURE BELT TENSION
DEFLECTION 1/64" PER INCH OF SPAN
OR 1.5mm PER 100mm OF SPAN
F-Field-Furnished Blower Drives
For field-furnished blower drives, use "BLOWER DATA"
(table of contents) to determine BHP and RPM required.
Reference table 2 for drive component manufacturer's
numbers.
DRIVE COMPONENTS
FIXED SHEAVE
OEM PART NO.
100244-20
31K6801
100244-17
100244-21
37L4701
12L2501
49K4001
100244-24
100244-23
FORCE
FIGURE 8
BELT
BROWNING NO. OEM PART NO.
A44 44L5501
AX45 100245-23
A41 100245-18
AX48 100245-50
AX48 100245-50
AX46 31K7101
BX50 100245-49
BX46 100245-48
BX46 100245-48