Emerson SENSI TOUCH 2 1F96U-42WF Series Installation Manual page 13

NOTES
ACCESSORY DEVICE
2-Wire accessory
Device has it's own power
source to turn the unit on.
Set switch on the back of
the thermostat to "Accessory."
1-Wire accessory
Device pulls power from the
HVAC system. Set switch on the
back of the thermostat to "System."
Sensi Touch 2 Smart Thermostat | INSTALLATION GUIDE
Accessory
Wire 1
Wire 2
Accessory
24V
24VAC switch
Accessory
System
Thermostat
ACC+
ACC-
Thermostat
ACC+
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