Operating Manual
Troubleshooting
If you have difficulty with your thermostat, please try the following.
Most problems can be corrected quickly and easily.
Display is blank
No response to
key presses (or
temperature
does not
change)
Backlight is dim
No "CLOCK"
button
69-2539EFS—01
• Check circuit breaker and reset if necessary.
• Make sure power switch at heating & cooling system is ON.
• Make sure furnace door is closed securely.
• Check to make sure the thermostat is not locked (see page 19).
• Make sure heating and cooling temperatures are set to acceptable
ranges:
• Heat: 40° to 90°F (4.5° to 32.0°C)
• Cool: 50° to 99°F (10.0° to 37.0°C)
• If thermostat is AC powered, a dim display is normal. The backlight
remains ON at a low level, and brightens when a key is pressed.
• If the clock button is not visible, the time displayed is being controlled
by the utility. If the time displayed ever varies from the actual local
time by more than a few minutes, please contact your utility as this
may indicate a communications problem.
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