Carrier AQUAZONE 50PSH, Installation, Start-Up And Service Instructions Manual

Page: 39 / 64

39
Step 9 — Wire Control Connections
COMPLETE C AND DELUXE D CONTROL
Control wiring for units with PSC and Constant Torque blower
motors are connected to a terminal block located in the unit elec -
trical box. Refer to the unit wiring diagram for connection details.
Units with Complete C or Deluxe D control packages can be con -
trolled using the included thermostat inputs (R, O, Y1, C, G) for
single stage heat pump thermostat or field-installed DDC (Direct
Digital Controls) controls. Note that the reversing valve on the
unit is energized when the unit is in the cooling mode. See Fig. 33
for typical thermostat connections.
Fig. 33 — Typical Thermostat Connections
Control wiring for units with constant airflow ECM blower mo -
tors is routed through a constant airflow ECM interface board.
Thermostat input wiring is connected to the 10-pin screw type ter -
minal block on the lower center portion of the ECM Interface
Board. In addition to providing a connecting point for thermostat
wiring, the interface board also translates thermostat inputs into
control commands for the Electronic Commutated Motor (ECM)
DC fan motor and displays an LED indication of operating status.
Refer to the unit wiring diagrams for complete details. See Fig. 34.
The thermostat connections and their functions are as follows:
ECM INTERFACE THERMOSTAT CONNECTIONS
• Y1 First Stage Compressor Operation
• Y2 Second Stage Compressor Operation
• G Fan
• O Reversing Valve (energized in cooling)
• W1 Auxiliary Electric Heat (runs with compressor)
• EM/W2 Emergency Heat (electric heat only)
• NC Transformer 24 VAC Common (extra connection)
• C1 Transformer 24 VAC Common (primary connection)
• R Transformer 24 VAC Hot
• H Dehumidification Mode
THERMOSTAT AND DDC SENSORS
Thermostats or DDC space sensors should be located on an interi
-
or wall away from supply ducts. Avoid locations subject to direct
sunlight or drafts, or external walls. Thermostat wiring should be
18 AWG (American Wire Gage). Refer to the installation instruc -
tions for the thermostat for further details.
HOT GAS REHEAT CONTROL
Units with hot gas reheat (HGRH) will include an additional H
terminal on the input terminal board for dehumidification control.
To enable a call for dehumidification, a 24V signal must be sent to
the H terminal with no voltage applied to the Y1 or O terminals.
Any call for cooling (Y1 and O) will override the dehumidifica -
tion call.
AUXILIARY RELAY (DELUXE D ONLY)
All units with Deluxe D control include an auxiliary relay that can
be field wired to enable a field provided loop pump or solenoid
valve when there is a call for compressor operation. See Fig. 17.
Fig. 34 — ECM Interface Board Physical Layout
WARNING
To avoid possible injury or death due to electrical shock, open
the power supply disconnect switch and secure it in an open
position during installation.
CAUTION
Never route control wiring through the same conduit as power
supply wiring. Electrical noise and transients from the power
wiring can cause communication issues or damage to the con -
trol wiring and connected control components.
C O
Y
R
G
IMPORTANT: Exceptionally long runs of thermostat wire
should be avoided to prevent voltage drops in the control circuit.
R R
C1 C2
10
EM
W1
O
Y2
Y1
G
H
C
W2
W1
O
Y2
Y1
G
CFM
H
CFM ADJUST
A
B
C
D
NORM
[+]
[-]
TEST
HGRH
YES NO
HGRH
J01
R C G O Y1 Y2 W1 W2 H C
1
3
9 8
7
6 5
2
4
11
LEGEND
1 Motor harness plug
2 Blower CFM adjustment
3 Motor settings
4 Dehumidification indication
5 Thermostat digital contact inputs
6 CFM count indicator
7 Thermostat input status indication
8 Reheat digital outputs
9 Thermostat outputs
10 24 VAC
11 Dehumidification method selector