Carrier 38AK - Manual (Page 6)

Install the sensor for thermistor input control on the header
tube designated in Fig. 13 and 14. Insert relay into socket.
Install the Motormaster® III relay in the unit control box,
in the location specified in Fig. 15 and 16. Use the two
no. 6-20 X 3/4-in. screws provided.
Connect one sensor lead to the violet control signal lead
on the Motormaster III controller and to a field-supplied
16 AWG wire with a wirenut. Connect the remaining
sensor lead to the gray control sensor lead on the
Motormaster III controller and to another field-supplied
16 AWG wire with a wirenut.
Route both field-supplied wires through a factory-
punched access hole under the control box. Attach the wires
to screw terminals 1 and 9 on the Motormaster III relay in
the control box. Wrap and tie excess sensor wiring. Wrap
wirenuts with waterproof tape to prevent them from loos­
ening and to ensure watertightness. Refer to Step 4 - Make
Electrical Connections and the unit wiring diagram for more
information on wiring the sensor.
A CAUTION
Sensor assembly is delicate. Handle with care.
Step 4 — Make Electrical Connections
NOTES;
1
A WARNING
To avoid possibility of electrical shock and personal
injury, turn off all power to unit before making elec­
trical connections. Tag all disconnects to alert others
not to turn on power until work is completed.
The wires necessary for wiring the Motormaster III con­
trol to the unit must be field-supplied. Use 16 AWG (Amer­
ican Wire Gage) (1.5 mm^) appliance material wire, with
2/64-in. (.8 mm) minimum insulation thickness. Use 75 C
type or equivalent. All wiring must comply with NEC
(National Electrical Code) and applicable local codes.
38AK008,012 AND 38AKS008-012 UNITS - Power wir­
ing must comply with all local and national electrical code
(NEC) requirements. Refer to Eig. 17-19 for power wiring
connections. Utilize field-supplied wirenuts and 'A in.
insulated female quick-connects for making power wiring
connections. Wrap wirenuts with waterproof tape to pre­
vent them from loosening and ensure watertightness.
NOTES;
1. On 50 Hz units, disconnect the yellow wire connected
to terminal 22 of the compressor contactor (C).
2. See wiring diagram on unit for more details.
48/50HJ008-014 AND 48/50TJ008-014 UNITS - Power
wiring must comply with all local and National Electrical
Code (NEC) requirements. Refer to Fig. 20-25 for power
wiring connections. Utilize field-supplied wirenuts and
V4-in. insulated female quick-connects for making power
wiring connections. Wrap wirenuts with waterproof tape to
prevent them from loosening and ensure watertightness.
On 220 V, 50 Hz units, disconnect the black wire con­
nected to capacitor 1. On 400 v, 50 Hz units, disconnect
blue wire connected to capacitor 1. Cap wire with a wire­
nut (50TJ008-014 only).
2. See wiring diagram on unit for more details.
38AQS008 AND 50LJQ008,012 UNITS - Power wiring
must comply with all local and National Electrical Code
(NEC) requirements. Refer to Fig. 26-28 for power wiring
connections. Utilize field-supplied wirenuts and 'A-in. in­
sulated female quick-connects for making power wiring con­
nections. Wrap wirenuts with waterproof tape to prevent
them from loosening and ensure watertightness. See wiring
diagram on unit for more details.
Step 5 — Install Field-Fabricated Wind Baffles
and Brackets
A WARNING
To avoid the possibility of electrical shock, open
all disconnects before installing or servicing this
accessory.
Wind baffles must be field-fabricated for all units to en­
sure proper cooling cycle operation at low-ambient temper­
atures with Motormaster III controls. See Fig. 29 and 30
for number and sizes of baffles required and for baffle de­
tails. Use 20-gage (1 mm) galvanized sheet metal or similar
corrosion-resistant material for the baffles. Use field-
supplied screws to attach baffles to unit. Screws should be
'A-in. (6.3 mm) diameter or larger. Drill required screws
holes for mounting the baffles.
A CAUTION
To avoid damage to refrigerant coils and electrical com­
ponents, use extreme care when drilling screw holes
and screwing in fasteners.
Step 6 — Restore Power To Unit - When all elec­
trical connections have been made, ensure they are tight
and correct.
1. Restore power to the unit.
2. Check the phase sequence indicator on the Motormaster
III control. It should not be lit. If lit, turn off power and
reverse LI (black) and L2 (yellow) power leads. See
Fig. 3.
3. With phasing on Motormaster III control correct,
make sure that the fan motors are rotating in the
proper direction. If fan rotation is backwards, shut off
power. Reverse the supply power leads between the
Motormaster III control and the condenser fan motor to
correct rotation.
4. Reinstall control box cover.
5. Reinstall unit access panel.