Parts Manuals User guide
Form P-RDF, P/N 270069 R6, Page 20
Drives
Belt Tension - Check belt tension. Proper belt tension is important to the long life of the
belt and motor. A loose belt will cause wear and slippage. Too much tension will cause
excessive motor and blower bearing wear. If adjustment is required, adjust belt tension
by means of the adjusting screw on the motor base until the belt can be depressed
1/2" to 3/4". Tighten the lock nut on the adjusting screw. Be sure the belt is aligned in
the pulleys.
Blower Speed Adjustment - Units are set at the factory for the RPM required to meet
the CFM and external static pressure specied on the order. If the estimated external
static is incorrect, or changes are made to the duct system, the blower RPM may have
to be changed. Motors are equipped with adjustable pitch pulleys which permit adjust-
ment of blower speed.
To make adjustments on all RDF-1 units and on RDF-2 and RDF-3 units with less
than 7-1/2 HP motor (units with a Browning motor sheave Model VP), follow these
instructions:
1) Loosen belt tension and remove belt.
2) Loosen the set screw on the side of the pulley away from the motor.
3) Turn adjustable half of the pulley inward to increase blower speed or outward
to decrease speed. One turn of the pulley will change speed 8 to 10%.
4) After setting the pulley, tighten the set screw on the at portion of the pulley
shaft.
5) Replace belts and adjust belt tension.
6) Always check motor amps with an amp meter after RPM adjustment. The
maximum motor amp rating on the nameplate must not be exceeded.
In RDF-2 and RDF-3 models with 7-1/2 HP and larger motors (units with adjustable
Browning motor sheave Model MV), follow these instructions for adjusting RPM:
1) Slack off all belt tension by moving the motor toward driven shaft until
the belts are free of grooves. For easiest adjustment, remove the belts
from the grooves.
Replacement Drive
Components are Listed
in Tables on pages 23-31.
Tables are by RDF Size,
Type of Motor, Motor HP,
and RPM (Option AM, see
chart top of page 23),
CODE 200 - Motor Sheave
CODE 201 - Blower Sheave
CODE 202 - Belt
CODE 203 - Bushing
NOTE: Read each drive
table carefully. They are
not all in the same format.
CODE Description 1-20 1-40 1-50 1-65 2-80 2-120 3-180 3-260
180
Blower with shaft and
bearings
P/N 1357 1360 86983 86984 92343* 89345 91067 91069
Size 10" 12" 15" 18" 18" 20" 22" 30"
Mfg # A10-10AC A12-12AC A15-15A A18-18A 022920-03
027550-02
A20-20K
020350-01
A22-22K
029353-02
A30-22K
Class Class 1 Class 1 Class 1 Class 1 Class 1
Shaft 1" 1-7/16" 1-7/16" 1-7/16" 1-11/16"
P/N — — — — 89658 — 91068 91070
Size 18" 22" 30"
Mfg #
0217142-15
A18-18A
029353-01
A22-22K
029353-03
A30-22K
Class Class 2 Class 2 Class 2
Shaft 1-7/16" 2-3/16" 2-11/16"
180A
Blower Shaft
Class 1
Blowers
11302
3/4x22
11303
1x22
100747
1x23
100748
1x28.8
100748
2x28.8
100746
1.44x37.25
100751
1.44x45.73
100754
1.69x46.25
Class 2
Blowers
— — — —
100749
1.44x38.5"
—
100752
2.19x45.75"
101705
2.69x46.25'
180B Blower Bearings
Class 1
Blowers
7310
10437 106942 106942 100755
Ball Bearings (2)
1.44" 1.44" 1.69"
Pillowblock (2)
Class 2
Blowers
— — — —
106942
—
100753 101710
1.44" 2.19" 2.69"
Pillowblock (2) Pillowblock (2)
181
External Shaft Support Bearing Plate 111389
- for units with dampers (Options AQ3, AQ4 and/or AR19, AR20, AR22, AR23) 126588** 126588** —
182 Bearing BF-1127-502-A - for units 111390
183
Blower Motor Mounting Plate 12578 94371
with dampers, Options AQ3, AQ4, and/or AR19, AR20, AR22, AR23)
184 Motor Mounting Plate Left Support 87015 94369
185 Motor Mounting Plate Right Support 87016 94369
186 Blower Support (Horizontal Discharge) 207840 (2)207461 (3)207462
*Effective 8/90, RDF 2-80 models are no longer manufactured with a Class 1 blower. P/N 92343 is no longer available. Replace with Class 2
blower, P/N 89658 and Q1-1-7/16" Bushing, P/N 16177.
** Order P/N 126588 when heater has Option AR23, outside and return dampers controlled by a remote pressure sensor.
Blower and Motor Mounting (cont'd) - See illustrations on page 19.