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15
Cooling —
Compressor (see Reversing Valve) and fan
turn on automatically when temperature rises (see Dead-
band) above set point. Compressor has a 15-second delay
before activation. After first cooling call, compressor and
fan will turn on automatically when temperature rises
above set point. Compressor will turn off when tempera-
ture drops below set point.
Heating —
Compressor (see Reversing Valve) and fan
turn on automatically when temperature drops below set
point. Compressor will activate 15 seconds after fan turns
on.
Auxiliary heat will become active only after the first
3 minutes of compressor operation. Once active, auxiliary
heat will remain on until set point is satisfied or has operat-
ed for more than 3 minutes. Auxiliary heat will automati-
cally turn on when temperature drops 4 F below set point.
After first heating call, compressor and fan wlll turn on
automatically when temperature drops below set point.
Compressor will turn off when temperature rises above set
point.
Deadband —
Deadband is active on start-up or initial
heating or cooling requirement. When temperature is with-
in 2 F of set point, the fan outputs will be off.
Fan operation will be as specified above.
Reversing valve will remain active.
Reversing valve (heat pump only) —
Type B valves
will energize in Heating mode. Reversing valve will turn on
15 seconds prior to heat/cool activity. Reversing valve will
deenergize 3 minutes after compressor call. Reversing
valve will remain inactive for cooling.
Default mode —
For 75 to 90 seconds after power has
been removed, the comfort set point (CS) of 72 F (pro-
gram default) is automatically provided upon restoration of
power. Default operating mode is Run mode. The default
value can be restored by changing the scale.
Diagnostic mode —
The Diagnostic mode may be in-
voked for maintenance purposes to verify thermostat per-
formance. This mode is activated by holding the UP and
DOWN arrow buttons for three seconds. The LCD will dis-
play fan operation, current cool or heat status, set point
and room temperature.
To deactivate diagnostic mode, press the FAN button re-
peatedly or change scale with the slide switch.
Scale change —
Move the slide switch to C to display
Celsius. Move the slide switch to F to display Fahrenheit.
Changing the scale wlll automatically reset the default com-
fort set point and run mode operation.
Time delays
• 3-minute delay (minimum) between Off and On
• 1.5-minute delay (minimum) between On and Off
• 3-minute delay (minimum) for auxiliary heat