BATTERIES ONLY - This thermostat can run on batteries only using 2AAA
alkaline batteries. The batteries will last at least 1 year; replace the batteries
once a year or when the low battery icon comes on the display. If the batteries
are not replaced, the thermostat will shut off the HVAC and then stop working.
24VAC - This thermostat can run on the HVAC 24VAC (C wire) if available.
As shown in the wiring diagrams, the C wire is the other side of the 24VAC
heating transformer and can be found where the other thermostat wires
connect at the wall or at the furnace. Do not use the common or ground side
of the line voltage. If the C wire is used, the batteries are then for back-up in
case of power loss only and will last much longer. With the C wire connected,
the thermostat will continue to work if the batteries die or are removed.
Power Options
PG
14
PG
13
NOTE:Your thermostat comes from the factory calibrated to +/- 1
o
of actual
temperature. 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:
Set the Mode switch to HEAT or COOL.
Locate the TIME SET button and press it. The
current calibration factor (+/-) of the 3M-22 will appear
in the LCD display as well as the modified temp.
Push the UP or DOWN arrows until the desired
calibration factor is reached.
Press HOME to save. The new calibrated temperature
will be displayed on the LCD.
Calibration
Calibrate button