D

69-1538 4
USING THIS GUIDE
The T8665C,D,E Communicating Thermostat
uses two-way radio frequency (RF) to send and
receive information. This information can be
used to make changes to your thermostat
settings, or settings from your Energy Utility.
The following symbols will help you identify the
features that apply to your system:
—–Tip symbol. Look for helpful
tips throughout this guide
when you see this symbol.
— – Compressor with the word,
Heat Pump, below.These
features are availble when
used with a heat pump.
Keyboard and Display Description
Keyboard
The keyboard is located behind the thermostat
cover. Three frequently used keys: increase ,
decrease , and i key are located next to the
display. See Fig. 1.
Display
The thermostat displays important information
such as day, time, schedule period,
temperature, filter information, system and fan
operation. See Fig. 2.
WARNING: This product operates under
provisions of Part 15 of the FCC Rules.
Modifications to this product not specifically
authorized by Honeywell may void the user’s
authority to operate this device.
80
90
70
60
90
80
70
60
H
EAT PUMP