Carrier 38AU 16 Series - Page 17

17
DISCONNECT ALL POWER TO UNIT AND CONVE-
NIENCE OUTLET.
Remove the blank cover plate at the convenience outlet; discard
the blank cover.
Loosen the two screws at the GFCI duplex outlet, until approxi-
mately 1/2-in. (13 mm) under screw heads are exposed. Press the
gasket over the screw heads. Slip the backing plate over the screw
heads at the keyhole slots and align with the gasket; tighten the
two screws until snug (do not over-tighten).
Mount the weatherproof cover to the backing plate as shown in
Fig. 17. Remove two slot fillers in the bottom of the cover to per-
mit service tool cords to exit the cover. Check for full closing and
latching.
Fig. 17 — Weatherproof Cover Installation
ALL UNITS
Voltage to compressor terminals during operation must be within
voltage range indicated on unit nameplate. See Tables 13 and 14
(on page 18). On 3-phase units, voltages between phases must be
balanced within 2% and the current within 10%. Use the formula
shown in the legend for Table 13, Note 5 (see page 19) to deter-
mine the percent of voltage imbalance. Operation on improper
line voltage or excessive phase imbalance constitutes abuse and
may cause damage to electrical components. Such operation
would invalidate any applicable Carrier warranty.
FIELD CONTROL WIRING
The 38AU unit control voltage is 24 v. See Appendix B Wiring
Diagrams (on pages 40-55) for typical field control connections
and the unit’s label diagram for field-supplied wiring details.
Route control wires to the 38AU unit through the opening in unit’s
end panel to the connections terminal board in the unit’s control
box.
Remainder of the system controls connection will vary accord-
ing to the specific construction details of the indoor section (air
handler or packaged fan coil). Figures 18 (38AUZ) and 19
(38AUD) depict typical connections to a Carrier 40RU fan coil
unit. Plan for field connections carefully and install control wir-
ing correctly per the project plan. Additional components and
supplemental transformer accessory may be required.
The 38AU unit requires an external temperature control device.
This device can be a thermostat (field-supplied).
THERMOSTAT
Install a Carrier-approved accessory thermostat according to in-
stallation instructions included with the accessory. For typical
thermostat connections see Figures 18 (38AUZ) and 19 (38AUD).
Locate the thermostat accessory on a solid wall in the conditioned
space to sense average temperature in accordance with the ther-
mostat installation instructions.
Fig. 18 — Typical Remote Thermostat Connections -
38AUZ
Fig. 19 — Typical Remote Thermostat Connections -
38AUD
The 38AUZ is a single-circuit, two-stage cooling unit. Select a
two-stage cooling thermostat, with or without supplemental heat-
ing as needed.
Cover — While-In-Use
Weatherproof
Baseplate For
GFCI Receptacle
Gasket
GFCI Receptacle
Not Included
T
O
P
TO
P
TOP
W
E
T
LOC
A
TI
O
N
S
W
E
T
L
O
C
A
TI
O
N
S
NOTES:
1. Connect only if thermostat requires 24-vac power source.
2. Connect W1 and W2 if supplemental heaters are installed.
3. Y2 connection for Single Circuit/2-Stage units only.
Field Wiring
(Note 1)
(Note 2)
(Note 3)
(Note 2)
LEGEND
(Note 1)
(Note 2)
(Note 3)
(Note 3)
1. Typical multi-function marking. Follow manufacturer’s configuration instructions to select Y2.
2. Connect only if thermostat requires 24-vac power source.
3. Connec
t W1
and W2 if supplemental heaters are ins
talle
d.
Field Wiring
LEGEND
NOTES: