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19
Step 7 — Adjust Indoor-Fan Speed —
Adjust indoor-
fan rpm to meet jobsite conditions.
Table 5 shows fan rpm at motor pulley settings for the
50HJQ004-007 units. Tables 6 and 7 shows data for indoor-fan
motors. Refer to Table 8 for accessory and option static pres-
sure drops, see Table 9 for indoor-fan motor efficiency, see
Tables 10-25 to determine fan speed settings.
For units with electric heating, required minimum cfm is
900 for 50HJQ004; 1200 for 50HJQ005; 1500 for 50HJQ006
and 1800 for 50HJQ007.
BELT-DRIVE MOTORS — Fan motor pulleys are factory-
set for speed shown in Table 1. Check pulley alignment and
belt tension prior to start-up.
To change fan speed:
1. Shut off unit power supply and tag disconnect.
2. Loosen belt by loosening fan motor mounting nuts. See
Fig. 33.
3. Loosen movable pulley flange setscrew (see Fig. 34).
4. Screw movable flange toward fixed flange to increase
speed or away from fixed flange to decrease speed.
Increasing fan speed increases load on motor. Do not ex-
ceed maximum speed specified in Table 1.
5. Set movable flange at nearest keyway of pulley hub and
tighten setscrew. (See Table 1 for speed change for each
full turn of pulley flange.)
To align fan and motor pulleys (see Fig. 34):
1. Loosen fan pulley setscrews.
2. Slide fan pulley along fan shaft.
3. Make angular alignment by loosening motor from
mounting.
To adjust belt tension:
1. Loosen fan motor mounting nuts.
2. Slide motor mounting plate away from fan scroll for
proper belt tension (
5
/
8
-in. deflection with 7 to 10 lbs
force).
3. Tighten motor mounting nuts.
4. Adjust bolt and tighten nut to secure motor in fixed
position.
Table 5 — Fan Rpm at Motor Pulley Settings*
*Approximate fan rpm shown.
†Indicates high-static motor and drive package.
UNIT
50HJQ
MOTOR PULLEY TURNS OPEN
0
1
/
2
1
1
1
/
2
2
2
1
/
2
3
3
1
/
2
4
4
1
/
2
5
5
1
/
2
6
004
1090
1055
1025
990
960
925
890
860
825
795
760
—
—
004†
1455
1423
1392
1360
1328
1297
1265
1233
1202
1170
1138
1107
1075
005
1185
1150
1115
1080
1045
1015
980
945
910
875
840
—
—
005†
1455
1423
1392
1360
1328
1297
1265
1233
1202
1170
1138
1107
1075
006
1460
1425
1385
1350
1315
1275
1240
1205
1165
1130
1095
1055
1020
006†
1685
1589
1557
1525
1493
1460
1428
1396
1364
1332
1300
—
—
007
1585
1540
1490
1445
1395
1350
1300
1255
1210
1165
1120
—
—
007†
1685
1589
1557
1525
1493
1460
1428
1396
1364
1332
1300
—
—
Fig. 33 — Belt Drive Motor Mounting
Fig. 34 — Evaporator-Fan Pulley Adjustment
Summary of Contents for 50HJQ004-007
Page 42: ...42 Fig 43 Typical Wiring Schematic 50HJQ006 007 Shown ...
Page 43: ...43 Fig 43 Typical Wiring Schematic 50HJQ006 007 Shown cont ...
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