Owner's Manual

When the batteries are low, the battery icon will come on and flash.

The two AA Batteries in the unit need to be replaced. In some installations your

heater system will stop functioning when the thermostat loses power. Replace

batteries as soon as you see this warning. The thermostat programs will remain

for 30 seconds while the batteries are removed and replaced.

Do not take longer than 30 sec to change the batteries in your unit

or you will lose all custom settings and all programming. Only the

Energy-Star

program will remain. Once the batteries are replaced,

the system will return to normal in 2 seconds.

NOTE: Your thermostat comes from the factory calibrated to + or - .5 degree F. It is an

accurate instrument. If you want your thermostat to display the same temperature as

another thermometer in your home, you can adjust its calibration.

To change the calibration:

Mode switch of the unit must be in the HEAT or COOL position.

Press the <Time

Press the Temp Up/Temp Down arrows to adjust the temperature reading.

Press HOME to save the new setting.

Calibration

Lock

Allows you to lock the Program (to prevent any changes in custom settings)

To enable or disable the program lock, press the following buttons one at a time, in

this sequence.

then FILTER, then SET CLOCK, and last HOME.

The LOCK icon (a key) appears when the system is locked.

Low Battery

PG 9

PG 10

Filter

The life of a heater filter varies depending on many factors, furnace run time,

and this will vary from the filter life noted on the filter media.

The 8050C has a feature that keeps track of actual furnace run time and

reminds you to periodically replace your system's air filter.

Press the FILTER button once to review the current filter record.

The FILTER and HR icons come on with accumulated filter hours being displayed.

Press to clear the record. Press again to recover the previous record.

To see the filter limit setting, press and hold the FILTER button for two seconds.

To change the filter limit hours setting, press F. or or B. Press and hold

for faster setting. The filter limit can be set within 000-500 hours.

To leave the filter display, press HOME or wait 60 seconds.

TIME

4 Special Features cont.