Installation manual

835966-UIM-D-0614
8 Johnson Controls Unitary Products
FIELD CONNECTIONS CONTROL WIRING -
COMMUNICATING
1. The Communication Harness (used in the outside heat pump unit) is
provided with the communicating thermostat.
2. Route low voltage four conductor shielded thermostat communica-
tions harness into junction box and connect to communications port
on control board. See Figures 5, 6, 7, and 8.
3. The complete connection diagram and schematic wiring label is
located on the inside surface of the unit service access panel.
4. Replace the corner cover and service access panel removed in
Steps 2 and 4 of the “Field Connections Power Wiring” section.
5. Route the 24-volt control wiring in accordance with national electri-
cal codes (NEC) Class 2 from the outdoor unit to the indoor unit and
thermostat.
6. All field wiring to be in accordance with NEC and/or local city codes.
7. Mount the thermostat about 5 ft. above the floor, where it will be
exposed to normal room air circulation. Do not place it on an outside
wall or where it is exposed to the radiant effect from exposed glass
or appliances, drafts from outside doors or supply air grilles.
.
FIGURE 6: Communications Harness Connection
If unit is going to be setup as a communicating system, the conven-
tional wiring must be removed from the Outdoor Control Board.
Ambient temperature sensor should extend below corner cover by 1”.
To eliminate erratic operation, seal the hole in the wall at the thermo-
stat with permagum or equivalent to prevent air drafts from affecting
the operation of the thermostat.
COMMUNICATIONS PORT
CONTROL BOARD
COMMUNICATIONS
HARNESS
JUNCTION
BOX
NOTICE
NOTICE
FIGURE 7: Communicating HP with Communicating Air Handler or
Furnace
FIGURE 8: Communicating HP with Non-Communicating Air Handler
or Furnace using Communicating Interface Control
Do not place more than one wire under any single communication
terminal screw (there are four communication terminal screws). If
more than one wire must be connected to a terminal screw, attach
only the terminal end of a one wire pigtail no longer than 6“, and
use a wire connector to connect the other end of the pigtail to the
other wires. Failure to do this will result in nuisance communication
error faults. See Figure 9.
FIGURE 9: Multi-wire Terminal Connection
R
C
Y1
Y2
Touch Screen
Communicating
Control
Air Handler/Furnace
Communicating
Control
Heat Pump
Communicating
Control
GND
or C
GND
or C
B-
R
A+
GND
or C
GND
or C
B-
R
A+
GND
or C
GND
or C
B-
R
A+
R
C
Y1
Y2
HUM
W2
DHUM
W
G
C
R
O
Y
Y2
HUM
W2
DHUM
W
G
C
R
O
Y
Y2
Touch Screen
Communicating
Control
Communicating
Indoor
Interface Control
Non-Communicating
Indoor Unit
Heat Pump
Communicating
Control
Wire per
non-comm.
installation
manual
Assume that
connections
are from
thermostat
GND
or C
GND
or C
B-
R
A+
GND
or C
GND
or C
B-
R
A+
GND
or C
GND
or C
B-
R
A+