Technical Guide

550569-YTG-D-1212
10 Johnson Controls Unitary Products
CONVENTIONAL CONTROL WIRING (24 VAC)
* Optional dehumidification humidistat switch contacts open on humidity rise.
CONTROL WIRING USING COMMUNICATION
Air Handler Control Wiring
Typical A/C - Cooling only Applications
THERMOSTAT
AIR HANDLER
BOARD
1-STAGE
AIR CONDITIONING
RR
G
Y
W1
W2
C
G
W1
W2
Y
C
Y/Y2
Y1
O
HUM
X/L
COM
HUMIDISTAT
*
THERMOSTAT
AIR HANDLER
BOARD
1-STAGE
AIR CONDITIONING
RR
G
Y
W1
W2
C
G
W1
W2
Y
C
Y/Y2
Y1
O
HUM
X/L
COM
HUMIDISTAT
*
Air Handler Control Wiring
Typical A/C with Electric Heat Applications
y
Two Stage H/P with York Guard VI Board & Copeland “Ultra Tech”
Conventional Application - Not Hot Heat Pump
THERMOSTAT
AIR HANDLER
BOARD
2 - STAGE SCROLL
HEAT PUMP
RR R
GG
Y2
E
W
W
O O
O
X/L X/L X/L
C
C
Y/Y2
Y1
Y1
Y2 OUT
Y2
W2 OUT
W1 OUT
BS
W2
W1
HUM
COM
HUMIDISTAT
*
Y1
7RXFK6FUHHQ
&RPPXQLFDWLQJ&RQWURO
$
5
%
&
$LU+DQGOHU
&RPPXQLFDWLQJ&RQWURO
&
%
5
:
:
$
2
+80
;/
5
*
<<
<
&20
$LU&RQGLWLRQHU+HDW3XPS
&RPPXQLFDWLQJ&RQWURO
&
%
5
$