Honeywell RTH8500 Manuel D'utilisation page 21

RTH8500
In case of difficulty
If you have difficulty with your thermostat, please try the suggestions below.
Most problems can be corrected quickly and easily.
Display is blank • Check circuit breaker and reset if necessary.
• Make sure power switch at heating & cooling system is on.
• Make sure furnace door is closed securely.
• If thermostat is battery powered, make sure fresh AAA alkaline batteries
Button on lower • This button will remain blank unless the furnace filter change reminder is
right of screen
is blank
are correctly installed (see page 18).
activated (see System Setup in your Installation Guide).
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