Source 1 S1-THEU21P7S Installation Instructions

Installation Instructions

Installation Instructions
TM
HVAC SERVICE PARTS
Turn off the power to the Heating/Air
Conditioning system at the main fuse panel.
Most residential systems have a separate
breaker for disconnecting power to the furnace.
Remove the cover of the old thermostat and
loosen the screws holding the thermostat base
or subbase to the wall to lift away.
Disconnect the wires from the old thermostat.
Tape the ends of the wires as you disconnect
them, and mark them with the letter of the
terminal for easy reconnection to the new
thermostat.
A COMMON WIRE MUST BE CONNECTED
IN ALL APPLICATIONS.
C
R
Y1
W1/O/B
G
W2
5 Wire, 1 Stage Heat Pump
O reversing valve.
Residential Heat Pumps, split systems
& package units, with no auxiliary heat.
5 Wire, 1 Stage Heat Pump
B reversing valve.
Residential Heat Pumps, split systems &
package units, with no auxiliary heat.
7 Day
7 Day
Programmable
Programmable

SAMPLE WIRING DIAGRAMS

COMMON
POWER
COMPRESSOR
REVERSING VALVE
FAN
COMMON
POWER
COMPRESSOR
REVERSING VALVE
FAN
MOD E
TERMINAL CONNECTIONS
Wire from the
old thermostat
terminal marked
W1, W or H
Y1 or Y
B
O
W2
G or F
Rh, R, M, Vr, A
C
6 Wire, 1 Stage Cool &
2 Stage Heat-Heat Pump
O reversing valve.
Residential Heat Pumps, split
systems & package units, with
auxiliary heat.
5 Wire, 1 Stage Cool &
Heat-Gas or Electric
Residential Gas or Electric
Heat, Electric Cool, split
systems & package units
to C
to R
to Y1
4 Wire, 1 Stage Heat
Gas or Electric
to W1/O/B
Residential Gas or Elec-
tric Heat units with a sep-
to G arately controlled fan.
to C
to R
4 Wire, 1 Stage Cool
Residential Electric Cool
to Y1
units.
to W1/O/B
to G
Control up to 2-Heat & 1-Cool
Control up to 2-Heat & 1-Cool
System Powered
System Powered
Backlit Digital Display
Backlit Digital Display
S1-THEU21P7S
Install on the
new thermostat
Function
connector marked
Gas Furnace W1/O/B
Electric Cool
Rev. Valve
W1/O/B
(Energize to Heat)
Rev. Valve
W1/O/B
(Energize to Cool)
Aux. Heat W2
Fan
Power
Common
COMMON
POWER
COMPRESSOR
REVERSING
VALVE
FAN
ELECTRIC
HEAT
COMMON
POWER
COOLING
GAS OR
ELECTRIC
HEAT
FAN
COMMON
POWER
GAS OR
ELECTRIC
HEAT
FAN
COMMON
POWER
COOLING
FAN
Auxiliary Heat Indicator
Auxiliary Heat Indicator

Fahrenheit or Celsius

Fahrenheit or Celsius
Model
Y1
G
R
C
to C
to R
to Y1
to W1/O/B
to G
to W2
to C
to R
to Y1
to W1/O/B
to G
to C
to R
to W1/O/B
to G
to C
to R
to Y1
to G