NOTE − All protection timers (except the compressor OFF timer) can be over−ridden if a heating or cooling demand is initiated or terminated using the UP, DOWN, HEAT, or COOL buttons.
Equipment Protection Override
Both the minimum compressor OFF timer and the mini- mum equipment cycle timer can be over−ridden by press- ing and holding either the HEAT or COOL button down for 4 seconds.
Over−Temperature Protection
Filter Reminder
Settings of Off, 1, 3, 6 or 12 (months of fan run time) are available. When programmed time has elapsed, a FILTER indicator is displayed.
Maintenance Reminder
Settings of Off, 6 or 12 (months of chronological time) are available. When programmed time has elapsed, a mainte- nance indicator
Service Reminder
The SERVICE indicator is displayed only under the follow- ing conditions:
Sif the thermostat Y1 terminal has been activated with 24VAC for at least 5 minutes, AND the L terminal is shorted to the R terminal;
OR
Sif the thermostat Y1 terminal has been activated with 24VAC for at least 5 minutes, AND the L terminal is shorted to the C terminal.
Power Loss/Recovery
Thermostat memory is retained for a minimum of 24 hours during a power loss (includes retention of clock setting, program information, HOLD status, programmed temper- ature setpoint, heat/cool and fan mode settings, filter re- minder status, maintenance reminder status, and equip- ment protection timers). After 24 hours of power loss, programmed settings will be lost and replaced with default settings.
IMPORTANT
Power must be applied for at least six consecutive hours prior to a power loss in order for memory to be retained for the specified time.
LCD Backlight
Activated for 30 seconds when any button is pressed.
NOTE − During an electrical storm or similar disturbance, the backlight may activate for a few seconds. This is nor- mal and will no longer occur after the electrical disturbance has passed.
Thermostat Operating Conditions
35°F to 105°F, 5% to 90% RH
Thermostat Storage Conditions
−40°F to 185°F, 5% to 95% RH
Page 9
51M39 SERIES 5/2