Pub. No. 18HD50D1-1A-EN 12/2018
Part No. 37-7768003
5
Trane XR203 Programmable Thermostat
4.5 Wiring Diagrams
NOTES:
1) Wire third party condensate overflow
switches between Y of the thermostat
and Y1 of the airflow control board
2) X2 is required to energize aux heat
during defrost
1 or 2 Stage Heat Pump with TAM7/TAM9 (24V Mode)
Indoor Unit
Outdoor Unit
Thermostat
Rc
Rh
O/B
Y
G
W/E
C
L
Y2
W2
R
R
O
O
Y1
G
W1
B
Y0
Y2
W2
W2
W2
W3
W2
BK
B
X2
Y/Y1
Y2
NOTES:
1) Y1 and Y0 connections must be made as shown
for freeze protection and internally mounted
condensate overflow circuits to function properly.
2) Wire third party condensate overflow switches
between Y of the thermostat and Y1 of the airflow
control board
1 or 2 Stage Cooling with TAM7/TAM9 (24V Mode)
Indoor Unit
Outdoor Unit
Thermostat
Rc
Rh
O/B
Y
G
W/E
C
L
Y2
W2
R
R
O
Y1
G
W1
B
Y0
Y2
W2
W2
W2
W3
W2
BK
B
Y/Y1
Y2
