Brand: Honeywell
Category: Thermostat
Manual Type:
Language:
Manual for TH8110U - Troubleshooting and error codes + PDF Download
Uploaded: April 8, 2025, 1:53 p.m.
Manual Publish Date: 2004-03-01
Warranty Summary
No warranty information is provided in this manual.
Using the Thermostat:
- Touch screen interface.
- Press keys with your fingertips.
- Use arrow keys to set Year, Month and Day.
- Use arrow keys to set current time.
System and Fan Settings:
- System Settings: Heat, Off, Cool, Auto.
- Fan Settings: Auto (default), can be programmed in schedule.
Troubleshooting and error codes
| Symptom | Possible Cause | Action |
|---|---|---|
| Display does not come on. | Thermostat is not being powered. | Check for 24 Vac between C and Rc. Verify AAA batteries installed correctly and 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. |
| Heating or cooling does not come on. | Thermostat minimum off-time is activated. | Wait up to five minutes for the system to respond. |
| 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; verify correct system type is chosen. Verify equipment operation in System Test mode. |
| Thermostat does not respond when touchpad is pressed. | The keypad is locked. | Check Installer Setup Number 0670 to change keypad locked options. |
Troubleshooting and error codes
| Symptom | Possible Cause | Action |
|---|---|---|
| Display does not come on. | Thermostat is not being powered. | Check for 24 Vac between C and Rc. Verify AAA batteries installed correctly and 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. |
| Heating or cooling does not come on. | Thermostat minimum off-time is activated. | Wait up to five minutes for the system to respond. |
| 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; verify correct system type is chosen. Verify equipment operation in System Test mode. |
| Thermostat does not respond when touchpad is pressed. | The keypad is locked. | Check Installer Setup Number 0670 to change keypad locked options. |