Carrier 50TJ016-028 Installation, Start-Up And Service Instructions Manual page 28

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NOTE: A 63-mm (2 / -in.) bolt and threaded plate are included in
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the installer's packet. They should be added to the motor support
channel below the motor mounting plate to aid in raising the motor.
The plate part no. is 50DP503842. The adjustment bolt is
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1 / -inch.
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Fig. 39 — 50TJ024 and 028 Evaporator-Fan
Motor Section
50TJ024,028 UNITS (See Fig. 39) —
028 units use a fan motor mounting system that features a
slide-out motor mounting plate. To replace or service the
motor, slide out the bracket.
1. Remove the evaporator-fan access panel and the heat-
ing control access panel.
2. Remove the center post (located between the evaporator
fan and heating control access panels) and all screws se-
curing it.
3. Loosen nuts on the two carriage bolts in the motor mount-
ing base.
4. Using jacking bolt under motor base, raise motor to top of
slide and remove belt. Secure motor in this position by
tightening the nuts on the carriage bolts.
5. Remove the belt drive.
6. Remove jacking bolt and tapped jacking bolt plate.
7. Remove the 2 screws that secure the motor mounting
plate to the motor support channel.
8. Remove the 3 screws from the end of the motor support
channel that interfere with the motor slide path.
9. Slide out the motor and motor mounting plate.
10. Disconnect wiring connections and remove the 4 mount-
ing bolts.
11. Remove the motor.
12. To install the new motor, reverse Steps 1-11.
Belt Tension Adjustment —
1. Loosen fan motor bolts.
2. Adjust belt tension:
a. Size 016 Units: Move motor mounting plate up or
down for proper belt tension (13 mm [
deflection with one finger).
b. Size 024,028 Units: Turn motor jacking bolt to
move motor mounting plate up or down for proper
belt tension (10 mm [
with one finger [4 kg (9 lb) force]).
3
/ -16 x
8
The 50TJ024,
To adjust belt tension:
1
/ in.]
2
3
/ in.] deflection at midspan
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NOTE: Dimensions are in mm (inches).
Fig. 40 — Condenser-Fan Adjustment
3. Tighten nuts.
4. Adjust bolts and nut on mounting plate to secure motor in
fixed position.
Condenser-Fan Adjustment (Fig. 40)
NOTE: For size 028 units with optional high-static condenser
fans, refer to section below for adjustment.
1. Shut off unit power supply.
2. Remove fan top-grille assembly and loosen fan hub
screws.
3. Adjust fan height on unit, using a straightedge placed
across the fan orifice.
4. Tighten setscrews and replace rubber hubcap to prevent
hub from rusting to motor shaft.
5. Fill hub recess with permagum if rubber hubcap is
missing.
Condenser Fan
Option, Size 028 Only) —
formed wire mount bolted to a fan deck and covered with a
wire guard. The exposed end of the fan motor shaft is protected
from weather by grease. If the fan motor must be removed for
service or replacement, be sure to regrease fan shaft and rein-
stall fan cover, retaining clips, and fan guard. For proper per-
formance, the fans should be positioned as shown in Fig. 41.
Tighten setscrews to 14 ± 1 ft-lb (18 ± 1.3 N-m).
Check for proper rotation of the fan(s) once reinstalled
(clockwise for high static and counterclockwise for standard
viewed from above). If necessary to reverse, switch leads at
contactor(s) in control box.
EconoMi$er Adjustment
LED INDICATION — The EconoMi$er controller features
an onboard diagnostic LED (light-emitting diode) that flashes
to indicate its status. See Table 20 for flash codes. The control-
ler also has terminal connections (LED) for remotely mounting
an LED, if desired. The flash code priorities are as follows:
1. On/Off or continuous flash
2. Critical fault
3. Non-critical fault
If any sensors are opened, shorted, or removed, the
EconoMi$er determines whether the failure is critical or non-
critical and flashes the appropriate code. If a non-critical sensor
fault occurs (i.e., outdoor air humidity), the EconoMi$er auto-
matically reconfigures its control strategy to a more appropriate
mode. If a critical sensor fault occurs (i.e., discharge air ther-
mistor), the EconoMi$er reverts to a safe mode of operation
until the sensor problem is resolved.
MANUAL CONFIGURATION PUSHBUTTON — The
EconoMi$er controller also features an onboard button (CON-
FIG) to help troubleshoot the system. The button can perform 3
different functions.
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Adjustment (High-Static
Each fan is supported by a