What do the LED’s below the display mean?
The LED’s indicate when the HVAC system is activated. With a call for heating or cooling, the HEAT or COOL LED will be illuminated.
THE AUX LED indicates the second stage of heating or cooling.
The CHECK LED is used only on the 9820i. It indicates the heat pump should be serviced by a qualified technician.
The EMER LED indicates that the emergency heat is turned on.
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