Owner's Manual & Installation Instructions

18 49-5000517 Rev. 2
Power failure Indicator
The programmable thermostats with battery backup also will
indicate a main power failure when the 24 VAC power from
the room air conditioner is not present.
Power failure
The thermostat will display a power failure
indication (“PF”) on the screen.
Note: If “PF” is displayed, it means the
24 VAC power to the thermostat is lost.