Honeywell TH8320U - TROUBLESHOOTING

69-1706 G.H. 01-04 www.honeywell.com/yourhome
TH8320U AND TH8321U TOUCH SCREEN PROGRAMMABLE THERMOSTATS
Automation and Control Solutions
Honeywell International Inc. Honeywell Limited-Honeywell Limitée
1985 Douglas Drive North 35 Dynamic Drive
Golden Valley, MN 55422 Scarborough, Ontario
M1V 4Z9
TROUBLESHOOTING (SEE TABLE 8)
Table 8. Troubleshooting.
Symptom Possible Cause Action
Display does not come on. Thermostat is not being
powered.
Check for 24 Vac between C and Rc.
Check that AAA batteries are installed
correctly and are good.
Temperature settings do not
change.
The upper or lower temperature
limits were reached.
Check temperature setpoints.
Check Installer Setup Numbers 0600 and
0610; modify as needed.
The keypad is fully locked. Check Installer Setup Number 0670 to
change keypad locked options.
Heating or cooling does not come
on.
Thermostat minimum off-time is
activated.
Wait up to five minutes for the system to
respond.
System selection is not set to
Heat or Cool.
Set system Selection to correct position.
O/B terminal is not set correctly
(Heat Pumps only).
Check Installer Setup Number 0190 and
set correctly.
System type Selection is
incorrect.
Check Installer Setup Number 0170 and
make sure correct System type is
chosen.
Thermostat is calling for Heat
(Heat on) or Cool (Cool on) but no
heating or cooling is running.
Heating or cooling equipment is
not operating.
Check wiring.
Check Installer Setup Number 0170 and
make sure correct system type is chosen.
Verify operation of equipment in System
Test mode.
Thermostat does not respond
when touch areas are pressed.
The keypad is locked. Check Installer Setup Number 0670 to
change keypad locked options.