Lennox CB29M-21, Unit Information

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Page 12
BLOWER ASSEMBLY
FIGURE 4
BLOWER MOTOR
CAPACITOR (C4)
BLOWER MOTOR
(B3)
BLOWER
HOUSING
BLOWER
WHEEL
I–Blower Motor (B3)
All CB29M and CB30M units use single phase direct
drive blower motors with a run capacitor. Figure 4
shows the parts arrangement. All motors use multiple
speed taps. Typically, the high speed tap is energized
during normal operation. The horse power for each
blower motor is listed in table 1.
All units are factory wired for the minimum blower speed
for heat pump and cooling applications with or without
electric heat. No field wiring is required. The wiring dia-
grams show factory set blower speeds. To run the blower
on high speed, refer to the installation instructions. All
speeds shown are minimums. Do not change motor taps
to operate at speeds lower than those shown in the tables.
460 Volt Blower Motor Windings
A third tap (blue) on 460 volt motors is used for internal
wiring during low speed operation and must not be
connected to line voltage. During low speed (yellow
tap) operation, the high speed (black) tap is discon-
nected from line voltage and is connected to the blue
internal wiring tap. This is done by the blower relay
(K3). For more information refer to Service and Applica-
tion Note (Corp. 8909–L7) on 460 volt blower motor
windings.
J–Blower Motor Capacitor (C4)
All CB29M and CB30M series units use single phase direct
drive motors with a run capacitor. The run capacitor is
mounted on the blower housing. See figure 4. Capacitor
ratings are shown in table 1.
TABLE 1
CB29M & CB30M BLOWER RATINGS
UNIT HORSE POWER
CAPACITOR
RATING
CB29M-21/26 (P) 1/5 HP 7.5MFD / 370V
CB29M-31 (P) 1/3 HP 5MFD / 370V
CB29M-41 (P) 1/3 HP 5MFD / 370V
CB29M-46 (P/G) 1/2HP 10MFD / 370V
CB29M-51 (P/G) 3/4 HP 10MFD / 370V
CB29M-65 (P/G) 3/4 HP 20MFD / 370V
CB30M-21/26 (P) 1/5 HP 7.5MFD / 370V
CB30M-31 (P) 1/3 HP 15MFD / 370V
CB30M-41 (P) 1/3 HP 15MFD / 370V
CB30M-46 (P) 1/3 HP 20MFD / 370V
CB30M-51 (P/G) 1/3 HP 20MFD / 370V
CB30M-65 (P/G) 1/2 HP 20MFD / 370V
K–Coil
All CB29M and CB30M series units have dual slab coils
arranged in an “A” configuration. Each coil has two or
three rows of copper tubes fitted with ripple–edged
aluminum fins. An expansion distributor feeds multiple
parallel circuits through the coils. The coil is designed to
easily slide out of the unit cabinet.
L–Plastic Drain Pans
Both upflow/downflow and horizontal drain pans are
provided and installed on the CB29M and CB30M units.
The drain pans are made from fiberglass filled plastic.
The drain hole is used for right-hand discharge only,
and must be plugged when the unit is configured for
left-hand discharge.