69-1507—2 G.H. Rev. 12-02
www.honeywell.com/yourhome
T8602D CHRONOTHERM
®
IV DELUXE PROGRAMMABLE THERMOSTATS
Printed in U.S.A. on recycled
paper containing at least 10%
post-consumer paper fibers.
Automation and Control Solutions
Honeywell
Honeywell Limited-Honeywell Limitée
1985 Douglas Drive North
35 Dynamic Drive
Golden Valley, MN 55422
Scarborough, Ontario
M1V 4Z9
System on indicator
(flame=heat,
snowflake=cool) is
displayed, but no
warm or cool air is
coming from the
registers.
Fan operation set for 0
(conventional heat) when it
should be set for 1 (electric
heat)
Enter Installer Setup number 2 and reconfigure the fan
operation.
Conventional heating equipment
turns on the fan when the
furnace has warmed up to a
setpoint.
Wait a minute after seeing the on indicator and then check the
registers.
Heating or cooling equipment is
not operating.
Verify operation of heating or cooling equipment in self-test.
Outdoor tempera-
ture not displayed
a
Option not activated.
Enter Installer Setup number 24 and set to 1. Thermostat must
have OT terminals and a C7089B1000 installed.
Outdoor
temperature
display is incorrect
a
Outdoor sensor is connected
incorrectly.
Refer to C7089B1000 Installation Instructions and check wiring
between the thermostat and sensor.
Wrong sensor.
Replace sensor with C7089B1000 Sensor.
Thermostat
backlight appears
dim.
Backlight can fade over the life
of the batteries.
• Wait until Replace Battery indicator is illuminated and
replace batteries.
• Replace batteries now.
a
Select models.
Table 6. Troubleshooting Guide. (Continued)
Symptom
Possible Cause
Action
