6
Terminal Function
One Stage Models RS4110, RS5110 and RS6110
TERMINAL
EQUIPMENT TO
CONNECT
DESCRIPTION
C
24V AC
Common
Connection
For input of 24V AC common side of transformer.
Connect to 24V AC common side of the trans-
former for line power and nightlight feature.
RH/R
24V AC
Hot Connection
Connect to 24V AC hot side of the transformer.
RC
24V AC
Hot Connection
Connect to 24V AC hot side of the cooling
transformer for two transformer systems.
Note: Remove jumper to Rh when RC is connected.
Y1*
First stage
compressor
connection
Energizes on a call for first stage of cooling.
Energizes on a call for first stage of heating when
configured as a HP.
W1*
First stage
heat connection
Energizes on a call for first stage of heating when
configured as a Non-HP.
G
Indoor fan
connection
Energizes with Y1 and Y2.
Energizes with W1 and W2 if the Gas/Elec switch
is set to electric.
Energizes when fan is switched to ON.
O
Energizes for heat pump cool reversing valve.
B
Energizes for heat pump heat reversing valve.
* This thermostat can be used as a heat-only or cool-only thermostat. Therefore, it
is not always necessary to use both W1 and Y1.
Two Stage Models RS4220, RS5220 and RS6220
TERMINAL
EQUIPMENT TO
CONNECT
DESCRIPTION
L
24V AC
Compressor Fault
Output
Connect to fault signal for input from
a compressor.
Y2
Second stage
cooling
connection.
Energizes on a call for second stage
cooling (aux.).
W2
Second stage
heat connection
Energizes on a call for second stage
heating (aux.).
E
Emergency Heat
Connection
Energizes on a call for emergency heat.
Three Stage Models RS4320 and RS6320
TERMINAL
EQUIPMENT TO
CONNECT
DESCRIPTION
E
Third stage heat
Energizes on a call for 3rd stage heat