Lux Products TX500U Installation And Operating Instructions Manual page 21

pump has different operating characteristics, you should refer to your heat
pump literature to determine when to disable the heat pump and run in
Emergency Heat mode.
LCD DISPLAY BACKLIGHT: The display screen is lighted to assist viewing at
nighttime, or in locations with low light levels. A press of any button on the
front panel will light the display for approximately 10 seconds. Any button
presses that occur while the light is on will reset the 10-second timer,
causing the screen to remain illuminated for an additional 10 seconds.
TEMPERATURE OVERRIDE: While in Program RUN mode, the set temperature
can be temporarily changed by pressing UP or DOWN. The set temperature
will return to the programmed value stored in memory when the start time of
the next upcoming program period is reached (Morn, Day, Eve, Nite). While
a Temporary Override is in effect, the word "OVERRIDE" will be shown in the
display screen. An Override may be cancelled moving the mode switch to
OFF, then back to HEAT or COOL.
MINIMUM RUN TIME: The thermostat has a default internal time delay of 5
minutes between load-on and load-off activations to prevent heating or
cooling system damage, which can occur from very frequent cycling. If
heating or cooling does not turn on right away with a manual change in set
temperature, please wait at least 5 minutes and the system should resume
normal operation.
TEMPERATURE HOLD: A Temperature Hold is used for maintaining a fixed set
temperature. Once a Hold is initiated, the thermostat will maintain the set
temperature indefinitely. A Hold may be used for days, weeks, or even
months at a time, as long as the thermostat has adequate power. To enter
Hold mode: press the HOLD button one time and the word "HOLD" will
appear in the display. To cancel a Hold, press the HOLD button one more
time. If a complete power failure occurs during a Temperature Hold, the
thermostat will continue to remain in Hold mode even after the power comes
back on. NOTE: If you plan to leave the thermostat in Hold mode for an
extended duration (unattended), it is advisable to install new Energizer ® or
DURACELL ® "AA" size alkaline batteries prior to leaving to ensure reliable
operation of your heating and cooling system.
STATIC NOTICE: This thermostat is protected against normal static electric
discharges, however to minimize the risk of damaging the unit in extremely
dry weather, please touch a grounded metal object before touching your
thermostat.
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