5803642-TIM-B-0620
Johnson Controls Ducted Systems
19
Thermostat Wiring
The thermostat should be located on an inside wall
approximately 56 inch above the floor where it will not be
subject to drafts, sun exposure or heat from electrical fixtures or
appliances. Follow the manufacturer's instructions enclosed
with thermostat for general installation procedure. Color-coded,
insulated wires should be used to connect the thermostat to the
unit. Refer to Table 8 for control wire sizing and maximum
length.
Typical Control Wiring Detail
Figure 22: Typical Control Wiring
Table 8: Control Wire Sizes
Wire Size
Maximum Length
1
1. From the unit to the thermostat and back to the unit.
18 AWG
150 Feet
OCC
C
RC
G
Y2
Y1
W2
W1
X
R
THERMOSTAT
TERMINALS
CONTROL
TERMINAL
BLOCK
TERMINALS ON A
LIMITED NUMBER
OF THERMOSTATS
1
4
3
1
2
4
Second stage
ŚĞĂƟŶŐŶ
ot required on single stage he
ĂƟŶ
g units.
Jumper is required if there is no Smoke Detector circuit.
Jumper is required for any co
ŵďŝŶĂƟŽŶ
of R, RC, or RH.
5
5
OCC is an output from the thermostat to indicate the Occupied
ĐŽŶĚŝƟ
on.
X is an input to the thermostat to display Error Status condi
Ɵ
ons.
3
W2
Y1
G
OCC
Y2
X
R
SD-24
C
W1
2
24V
C
24 VAC
Class 2
SD-24
Jumper Located on Harness
Smoke
Detector
SD-R
24V Output
R
(If No Smoke Detector)
(If Smoke Detector Is Used)
R~Occ Jumper:
Smart Equipment Control boards come from the
factory with a jumper wire between R and OCC
terminals on the thermostat terminal strip. Failure
to remove this jumper will place the unit into the
Occupied mode no matter what the occupancy
demand is from the thermostat or EMS system.
To allow Thermostat or EMS control of the
Occupied mode for the unit, this jumper must be
removed during commissioning.
