WARNING:
In heat pump applications, do not connect anything to the W1
terminal. When switched to HP mode, W1 is connected internally
to Y1 on the thermostat.
1. Turn off power to heating and cooling system.
2. Remove cover from old thermostat to expose wires (Figure 1).
3. Disconnect wires one at a time from existing terminals. Use enclosed
labels to mark existing wires. Refer to cross references in the Wiring Table
if existing wiring does not directly match the labels.
4. Remove existing thermostat base from wall.
Step 2: Installing Model 8401 Thermostat
NOTE: FOR NEW INSTALLATIONS, MOUNT THERMOSTAT ON
INSIDE WALL, FIVE FEET ABOVE THE FLOOR. DO NOT
INSTALL BEHIND A DOOR, IN A CORNER, NEAR AIR
VENTS, IN DIRECT SUNLIGHT, OR NEAR ANY HEAT OR
STEAM GENERATING FIXTURES. INSTALLATION AT THESE
LOCATIONS WILL AFFECT THERMOSTAT OPERATION.
1. Turn power off to the heating and cooling systems.
2. Place HEAT-OFF-COOL in OFF position (Figure 2).
3. Place
AUTO-ON switch into AUTO position (Figure 2).
3
Figure 1
heat off cool
auto on
°
F
Figure 2
heat off cool
auto on
°
F
!
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