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RTH4300B Programmable Thermostat
About your new thermostat
In case of difficulty
If you have difficulty with your thermostat, please try the following suggestions.
Most problems can be corrected quickly and easily.
Display is blank
• Check circuit breaker and reset if necessary.
• Make sure heating & cooling power switches are on.
• Make sure furnace door is closed securely.
• Make sure fresh AA alkaline batteries are correctly installed
(see page 14).
Heating or
cooling system
does not respond
• Set System switch to Heat. Make sure the temperature is set higher
than the Inside temperature.
• Set System switch to Cool. Make sure the temperature is set lower than
the Inside temperature.
• Check circuit breaker and reset if necessary.
• Make sure heating & cooling power switches are on.
• Make sure furnace door is securely closed.
• Wait 5 minutes for the system to respond.