• Please read all of these instructions carefully before beginning  
• Label every wire terminal designation on your existing thermostat wiring  
before removing your old thermostat.  
• Ignore the color of the wires since they may not comply with any  
standard. Please connect wires using the terminal letter designations.  
Thank you for your confidence in our product. To obtain the best results from  
your investment, please read and follow the installation procedures carefully, and  
one step at a time. This will save you time and minimize the chance of damaging  
either the thermostat or possibly your heating and cooling system. These  
instructions may contain information beyond that which may be required for your  
particular installation.  
CAUTIONS AND WARNINGS . . . . . . . . . . 2  
SYSTEM COMPATIBILITY . . . . . . . . . . . . 3  
FEATURES . . . . . . . . . . . . . . . . . . . . . . . 4  
TOOLS YOU MAY NEED . . . . . . . . . . . . . . 4  
MOUNTING LOCATION . . . . . . . . . . . . . . 5  
REMOVE OLD THERMOSTAT . . . . . . . . . . 5  
INSTALL THERMOSTAT BASE . . . . . . . . . 6  
WIRING INFORMATION . . . . . . . . . . . . . . 7  
WIRING DIAGRAMS . . . . . . . . . . . . . . . . 9  
COMPLETE THE INSTALL . . . . . . . . . . . 18  
FRONT PANEL ITEMS . . . . . . . . . . . . . . 18  
SETUP OPTIONS. . . . . . . . . . . . . . . . . . 20  
OPERATING INSTRUCTIONS . . . . . . . . . 23  
TEMPERATURE PROGRAMS . . . . . . . . . 25  
ADVANCED FEATURES . . . . . . . . . . . . . 26  
BATTERY REPLACEMENT . . . . . . . . . . . 31  
TECHNICAL ASSISTANCE . . . . . . . . . . . 32  
LIMITED WARRANTY . . . . . . . . . . . . . . 32  
MERCURY NOTICE . . . . . . . . . . . . . . . . 33  
WARNING: Use Energizer® or DURACELL® Alkaline Batteries Only.  
Energizer® is a registered trademark of Eveready Battery Company, Inc.  
DURACELL® is a registered trademark of The Procter & Gamble Company  
• This thermostat requires batteries to operate and failure or sub-standard  
performance of the batteries may impair or prevent the correct operation of  
the thermostat. Use Duracell® or Energizer® alkaline batteries ONLY for all  
LUXPRO thermostats requiring batteries. BE SURE TO CHANGE THE BATTERIES  
AT LEAST ONCE A YEAR, or whenever you see the LO BATT indication on the  
screen. Failure to follow these battery instructions could result in property  
damage and/or personal injury.  
• The electrical rating for this thermostat is 1.5 Amps per terminal, with a  
maximum total load of 3.0A for all terminals combined.  
• The thermostat contains parts that may wear out through use and are  
susceptible to failure if over-loaded or used in a manner other than as  
indicated in the documentation.  
• Check unoccupied residences regularly to ensure that all systems are  
operating properly.  
• Check any heating/air-conditioning system including this product before  
operation and at regular intervals.  
• Electrical interference, static electricity, failure or substandard performance of  
batteries, wiring defects in the installation and/or characteristics of the  
connected HVAC devices may prevent the system from regulating heating and  
cooling as anticipated.  
• The thermostat is a sensitive device and dropping the product can cause  
damage to critical components. If the product is dropped or shaken violently  
during transport or installation then it should be replaced immediately.  
• Persons with physical or mental limitations may not be able to promptly  
respond to a malfunction of the heating/air-conditioning system.  
• All residents should be made aware of the potential in any system for  
malfunctions that could cause continuous heating or cooling and should be  
familiar with the operation and location of the heating/cooling appliance on/off  
• Read the instruction manual completely before installing the thermostat. You  
should consult a qualified HVAC technician or an electrician if you do not fully  
understand the installation instructions.  
LCD Display Screen  
Fan Mode  
Set Slide  
System Mode  
UP / DOWN Buttons  
The electrical rating for this thermostat is 1.5 Amps per terminal, with a  
maximum total combined load of 3.0A for all terminals combined.  
• Most 24-volt heating and cooling systems  
• 1 or 2 stage Heat / 1 stage Cool: Gas, Oil or Electric systems  
• 1 or 2 stage Heat / 1 stage Cool: Heat Pump systems  
• 3-wire hydronic (hot water) zone valves  
• Gas Millivolt heaters  
• 120/240 VAC line-voltage systems (without a transformer), ask your LUXPRO  
dealer for thermostats to control these systems.  
• 1 or 2-Heat / 1-Cool, 5/1/1-day programming  
• Universal Compatibility for all system types  
• Weekdays, Saturday, and Sunday can be programmed separately  
• Exclusive LUX® Speed SlideTM for easy programming  
• User-selectable periods per day (2 or 4)  
• User-selectable programmable or non-programmable operation  
• LuxLight® EL (Electro-Luminescent) lighted display  
• Programmable air filter life timer  
• Graphical filter monitor  
• Keypad lockout for unauthorized users  
• Manual temperature hold  
• Adjustable vacation hold (1 to 30 days)  
• Temporary temperature override  
• Adjustable temperature differential / cycle-rate  
• Adjustable 2nd heat stage Offset setting  
• User temperature calibration  
• Adjustable heat/cool set temperature limit stops  
• Smart recovery  
• Dual-powered (battery and/or 24-volt system powered)  
• Battery-free memory storage  
• F/C temperature display  
• 12/24-hour clock display  
• 5/2-minute selectable time delay for equipment protection  
• Screwdrivers  
• Wire Stripper  
• Wire Cutter  
• Drill with assorted drill bits (new installations only)  
On replacement installations, mount the new thermostat in place of the old one  
unless the conditions listed below suggest otherwise. On new installations,  
please follow these general guidelines:  
1. Mount the thermostat on an inside wall, about 5 ft. (1.5m) above the floor.  
2. Do not locate the thermostat where air circulation is poor such as in a corner,  
alcove, or behind a door that is normally left open.  
3. Do not locate the thermostat where unusual heating or cooling conditions may  
be present, such as: direct sunlight, above a lamp, television, or radiator, or on  
a wall next to an exterior door or window.  
4. Do not locate in a damp environment, as this can lead to corrosion that may  
shorten thermostat life.  
5. If painting or construction work is still ongoing, cover the thermostat  
completely or wait until this work is complete before installation.  
All wiring must conform to the local codes and ordinances that are in your  
particular location.  
1. Turn OFF the electricity to all heating and cooling  
components. Do not turn the electricity back on until  
all work is completed.  
2. Remove the front portion of your old thermostat to  
expose the wiring connections.  
3. Write down the letters printed near each wire terminal  
that is used, and also the color of each wire that is  
connected to it. Self-adhesive wire labels are also  
4. Carefully remove the wires one at a time, and bend them in a manner so that  
they do not fall back inside the wall. Do not allow bare wire ends to touch  
each other.  
5. Loosen the mounting screws for the old thermostat and carefully remove it  
from the wall.  
1. Strip wire insulation leaving only 3/8 in. (9.5mm) bare wire ends, and clean off  
any corrosion present.  
2. Fill the wall opening with non-combustible insulation to prevent drafts from  
affecting the thermostat’s normal operation.  
3. Separate new thermostat housing using your thumb and index finger. Provide  
pressure in opposite directions to the release tabs on the top of the housing,  
in the directions shown in the diagram shown above.  
4. Route the wires through the opening in the new thermostat base plate, and  
hold the base against the wall. Try to line up the screw holes from the prior  
thermostat, and install the mounting screws.  
5. If the previous holes cannot be used, hold the thermostat base against the  
wall so that it appears straight and level (position the base for best  
appearance) and mark for the new screw holes. Attach the base to the wall  
using the screws provided (use the supplied plastic anchors if needed when  
mounting to a soft material such as drywall).  
When attaching the wires to the thermostat, please ensure that the bare wire  
ends are held ALL the way into the terminal block while the screw is being  
This thermostat model is part of a family of similar models that have the same  
general visual appearance. Even though this base plate may look the same as  
base plates from other models, the wiring connections may have different  
terminal letters for different purposes. Please do not interchange the back plates  
and/or thermostat front halves of other similar looking models. Doing so may  
cause undesired heating and/or cooling operation to occur.  
(Important, please read all notes before connecting wires)  
• If the information provided in the following wiring diagrams does not clearly  
represent or match your system, please refer to the “TECHNICAL ASSISTANCE”  
section of this manual, and contact us before removing any of your existing  
thermostat wiring.  
• All of the dashed wires shown in the wiring diagrams are either optional, or  
their usage depends upon your specific system type or brand. For example:  
Diagram #1 shows the fan wire as optional. If your system does not have a  
fan, than this terminal will not be used.  
• Terminal letters shown in black represent typical wiring applications.  
Depending upon the brand of your specific system or thermostat, your terminal  
letters may not match exactly. Terminal letters shown in gray represent other  
possible wiring designations that you might see on your existing thermostat  
• The optional “C” terminal is used for powering the thermostat by the 24-volt  
system, using the System Common wire. This can be used alone, or in  
addition to installing batteries as a backup. NOTE: connecting the System  
Common wire to the thermostat is not necessary for heating and cooling to  
function properly.  
• If your old thermostat has both a “Y” and “C” wire both present, then “C” is  
most likely a System Common wire.  
• For Heat Pump systems, you will use either the “O” terminal or the “B”  
terminal on this thermostat, but not both. If your old thermostat has both an  
“O” and a “B” wire present, then “B” is likely a System Common wire and may  
be connected to the “C” terminal. Connecting a System Common wire to this  
thermostat’s “B” terminal may damage the thermostat, and also your heating  
and cooling system.  
• Some Heat Pump systems have a wire for AUX electric heat (usually W2), and  
also a separate wire for Emergency electric heat (usually E). This thermostat  
uses the W2 terminal for both AUX and Emergency Heat. Tape off your “E”  
wire, and confirm that all components function without it.  
• If replacing an old thermostat that has a mechanical clock, there may be two  
wires labeled as “C” for the clock power. Tape off these wires and do not  
connect them to the “C” terminal of this thermostat.  
PAGE #  
HEATING ..........................................................10  
2, 3, 4, 5 WIRES  
HEATING ..........................................................11  
3, 4 WIRES  
COOLING ..........................................................12  
3, 4 WIRES  
HEATING AND COOLING .....................................13  
4, 5 WIRES  
HEATING AND COOLING .....................................14  
5, 6 WIRES  
HEATING AND COOLING .....................................15  
5, 6 WIRES  
HEATING AND COOLING .....................................16  
4, 5 WIRES  
HEATING AND COOLING .....................................17  
5, 6 WIRES  
INSTALL BATTERIES INTO THERMOSTAT: Install two brand new Energizer® or  
DURACELL® “AA” size alkaline (only) batteries, into the thermostat’s battery  
compartment. Ensure the batteries are installed in the proper direction.  
setting is a plastic shorting cap called a jumper. This jumper must remain  
installed, and set to either GAS or ELECTRIC for your system to work properly.  
This setting changes how your system’s blower fan (if applicable) is controlled  
while the thermostat is in HEAT or EMERG HEAT mode, when the Fan switch in  
the AUTO position. This setting does not affect the fan operation while in COOL  
When set to “GAS”, the blower fan is controlled solely by the heating system  
itself. Systems that would typically use the “GAS” setting would be: natural gas,  
propane, or oil furnaces, and boilers.  
NOTE: If your blower fan does not operate  
properly after installation, move the Gas /  
Electric option to the “Electric” setting.  
When set to “ELEC”, the blower fan is  
controlled directly by the thermostat. This  
setting is required for heating systems  
that do not control their own fan, such as  
HEAT PUMPS, and units that only have an  
electric-resistive heating element as the  
heat source.  
These items below are all located behind the door on the front of the thermostat.  
To open the door, pull outwards using the small indentation in the center of the  
top edge of the thermostat housing.  
HEAT / OFF / COOL, SYSTEM MODE SWITCH: Set this switch to HEAT to control  
your heating system, and COOL to control your cooling system. The OFF position  
will disable both the heating and cooling units.  
AUTO / ON, FAN MODE SWITCH: When this switch is in AUTO, the blower fan (if  
present in your system) will automatically cycle on and off by itself while heating  
or cooling is running. When in the ON position, the blower fan will run constantly  
with or without a demand for heating or cooling, even when the System Mode  
switch is in the OFF position.  
NOTE: The Fan Mode switch only works if your system provides a wire for the  
thermostat’s “G” wire terminal, to control a blower fan. The Fan Mode switch  
has no effect in systems that do not have a blower fan (such as a hot water  
radiator system).  
MULTI-FUNCTION, SET SLIDE SWITCH: This switch provides an easy way to  
quickly access the most commonly used thermostat settings. This switch has 4  
individual positions, and unless a specific setting is being adjusted, this switch  
should always remain in the RUN position for the thermostat to control the room  
temperature. The other Set Slide switch positions are described in greater detail  
in the ADVANCED FEATURES section. NOTE: this switch is only operable when the  
thermostat is in “Programmable” mode. When the thermostat is used in  
“Manual” control mode, all 4 of the switch positions will act like the RUN  
position, except the “AIR FILTER” position.  
SETBACK BUTTON: This button activates and deactivates the SETBACK feature,  
which overrides the set temperature for an adjustable duration. This feature is  
described in greater detail in the ADVANCED FEATURES section.  
UP / DOWN BUTTONS: The UP and DOWN buttons are used to adjust any item  
that can be changed by the user. Examples are the set temperatures, clock  
times, and days of the week. In many cases, an item may be flashing if it can  
currently be adjusted.  
HOLD BUTTON: This button activates and deactivates the manual Temperature  
Hold feature.  
EMER BUTTON: When in Normal Run mode, the usage of this button varies  
depending upon your specific system configuration. For heat pump systems,  
pressing this button enables your emergency heat function, which is described in  
greater detail in the OPERATING INSTRUCTIONS section. For conventional  
systems, there is no such thing as emergency heat, so this button will have no  
NEXT BUTTON: This button is mostly used while setting items such as software  
options, and temperature program periods. When there are several items on the  
screen that can be changed, usually one of them is flashing indicating that it can  
be adjusted. Pressing the NEXT button will cycle through which item is flashing.  
Setup options for how the thermostat will function, along with choosing your  
particular system type, are performed using a menu on the display screen.  
TO ACCESS THE SETUP MENU: Move the System Mode switch into the OFF  
position, and then hold down the EMER button for approximately 5 seconds until  
the screen changes. The menu will always start with item #1, and is advanced to  
each following item by a single press of the NEXT button. The options for each  
item are changed using the UP or DOWN buttons.  
ITEM #01 (CLK = CLOCK FORMAT): [12Hr, default] This displays the clock times  
using standard AM and PM values. [24Hr] This displays the clock times using the  
military-time format (example 22:00 hours, without using AM or PM).  
ITEM #02 (TMP = TEMPERATURE SCALE): [F, default] Shows all temperature  
values in Fahrenheit. [C] Shows all temperature values Celsius.  
ITEM #03 (THERMOSTAT TYPE): [PROG, default] Use this setting for following a  
daily program routine. [MAN] This setting omits the program routine and  
operates as a manual style non-programmable thermostat. This is very basic and  
only shows the room temperature and set temperature on the screen, with no  
ITEM #04 (PERD = PERIOD QUANTITY): [4P, default] Thermostat uses four  
periods per day (called MORN, DAY, EVE, and NITE). [2P] The thermostat uses two  
periods per day (called DAY and NITE).  
ITEM #05 (RCV = EARLY RECOVERY): [OFF, default] Program Set Temperature  
values start to occur at exactly the period start times. [ON] Early Recovery  
affects how the transition occurs when changing from the NITE to the MORN  
period, and when changing from the DAY to the EVE period. The thermostat  
calculates how long it takes for your home to recover from a setback on a daily  
basis, and turns on ahead of time in order to reach the target set point of the  
next upcoming program period by the period’s start time. While in a recovery,  
the word “RECOV.” will be shown on the display screen.  
ITEM #06 (SYSTEM MODE): [FURN, default] This is for the majority of heating  
systems that are not Heat Pumps, such as a gas furnace or hot water boiler. [HP]  
Use this setting if you have a Heat Pump system, which uses the outdoor unit as  
the primary heat source and may also contain an electric heating element as a  
backup heat source. When set to “HP”, ensure that you have also set the  
Gas/Electric circuit board option to “ELEC”, as described in the “COMPLETE THE  
INSTALL” section.  
ITEM #07 (DLAY = DELAY TIME): [5, default] Thermostat waits 5 minutes before  
turning the system back on after it was last run. This internal delay prevents  
rapid cycling and provides equipment protection. The 5 minute setting is fine for  
most applications. [2] Same operation as above but reduced to 2 minutes  
between state changes.  
ITEM #08 (TEMPERATURE SWING): A thermostat works by turning your heating  
or cooling system on and off whenever the room temperature varies from the  
desired set-point temperature. The amount of this variation is called the swing.  
Use the UP/DOWN buttons to change the number value between 1 and 9.  
Generally your system should cycle on about 3 to 6 times per hour. A smaller  
swing number makes the system cycle more frequently, so the room temperature  
is more precise and constant. A larger swing number will make the system  
remain on for a longer duration each time and decreases the number of cycles  
per hour.  
ITEM #09 (STAGE-2 OFFSET): [2, default] This setting is adjusted as a number  
from 0 to 9. When set to 0 (ZERO), the second heating stage is completely  
disabled while in regular Heat mode (however Emergency Heat mode will still  
function for heat pump configurations). An Offset value from 1 to 9 degrees will  
determine the number of degrees from the set point that will be required for the  
second heating stage to turn on. This setting can be used to conserve energy in  
situations where the second heating stage is more costly to operate when  
compared to the first stage.  
Cut-In / Cut-Out  
(1st Stage)  
70˚F Set  
#2 (+/- 0.5˚F)  
Offset **  
4˚F degrees  
(2nd Stage) **  
Cut-In / Cut-Out  
** = Only applies if a second  
heat stage is present  
SET DAY AND TIME: Place the Set Slide Switch into the DAY/TIME position. With  
the day flashing, press UP or DOWN to set the day of the week. Press NEXT and  
the clock time will start flashing. Use UP or DOWN to set the time, making sure  
the AM/PM indication is correct. Holding the UP or DOWN buttons will make the  
clock digits scroll rapidly. Return the Set Slide switch to the RUN position when  
HEATING AND COOLING: Basic operation of your heating or cooling system can  
be obtained with the Set Slide Switch in the RUN position and choosing either  
HEAT or COOL on the System Mode switch. The temperature can be adjusted  
using the UP and DOWN buttons. When the thermostat is first powered up, it will  
follow a default temperature routine that is preset from the factory (shown  
MORN 6:00 AM 70 °F (21 °C) 6:00 AM 78 °F (26 °C)  
8:00 AM 62 °F (17 °C) 8:00 AM 82 °F (28 °C)  
6:00 PM 70 °F (21 °C) 6:00 PM 78 °F (26 °C)  
NITE 10:00 PM 62 °F (17 °C) 10:00 PM 75 °F (24 °C)  
EMERGENCY HEAT: (Heat Pump Configuration Only). While in normal Heat mode  
with the Set Slide switch in the RUN position, one single press of the EMER  
button will activate Emergency Heat mode. A single press again will end  
Emergency Heat mode, and return back to normal Heat mode. While in  
Emergency Heat mode, the word “EMER” will also be shown in the middle portion  
of the display screen. If a power loss occurs while in Emergency Heat mode, the  
thermostat will continue to remain in Emergency Heat mode even after the power  
comes back on.  
Emergency Heat mode will prevent the first stage of your heat pump system from  
turning on, and use only the “W2” heat terminal (Auxiliary Heat) as the primary  
heating source. This will not only prevent the heat pump from wasting energy if  
outdoor temperatures are too low to support efficient operation, but it could also  
prevent damage to the heat pump if outside temperatures are below the  
manufacturer’s recommendations. As every heat 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. In general for most  
heat pump systems, use Emergency Heat mode whenever the outside  
temperature is less than 32°F (0°C) degrees.  
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.  
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.  
By default, this thermostat has 4 separate program periods for both Heat and  
Cool mode, they are: MORN, DAY, EVE, and NITE. Each period ends at the start  
time of the following period. The heat programs are set in HEAT mode, and the  
cool programs are set in COOL mode.  
NOTE: If the thermostat is configured to use only 2 periods per day instead of 4  
(SYSTEM CONFIGURATION AND SETUP OPTIONS), the thermostat will only use the  
DAY and NITE periods. The MORN and EVE periods will not be visible on the  
SET TEMPERATURE PROGRAMS: Move the Set Slide switch to the TEMP PROG  
position. Programming will start with all 5 weekdays, Monday through Friday (all  
grouped together). Use the UP/DOWN buttons to adjust the start time for the  
MORN period, then press the NEXT button to advance. Use the UP/DOWN buttons  
to adjust the set temperature for the MORN period, then press the NEXT button to  
advance. Now adjust the start time and set temperature for the DAY period,  
pressing the NEXT button after each to advance. Continue with these same steps  
to adjust the start times and set temperatures for the EVE and NITE program  
When the NITE period is finished for the weekdays, the thermostat will advance  
forward to the Saturday program, with the MORN period start time flashing.  
Perform the same steps that you used for setting the weekday periods, pressing  
the NEXT button to advance through each flashing value.  
When the Saturday NITE period is finished, the thermostat will advance forward  
to the Sunday program, with the MORN period start time flashing. Perform the  
same steps that you used for setting the Saturday periods, pressing the NEXT  
button to advance through each flashing value. Return the Set Slide switch to  
the RUN position when you are finished.  
TEMPERATURE CALIBRATION: The internal temperature sensor in this thermostat  
is accurately calibrated at the factory, and in most cases alterations to this  
setting should not be needed. The Temperature Calibration feature allows you to  
manually offset the measured temperature by as much as plus or minus 5°F  
(3°C) degrees from its original value. This feature can be useful to match or  
synchronize this thermostat to another one or more, if multiple thermostats are  
used in the same home.  
NOTE: The Temperature Calibration setting need to be performed in a timely  
manner, as the thermostat will timeout and automatically exit the adjustment  
screen after approximately 10 seconds without a button press.  
switch is in the OFF position and the Set Slide switch is in the RUN position.  
Press and hold both the UP and DOWN buttons together for at least 5 seconds.  
The words “SET” and “CALwill appear on the screen, along with a single  
flashing temperature digit. Use the UP/DOWN buttons to change the number of  
degrees of adjustment. 0° degrees is the default value, and means no correction  
is being applied. Press the NEXT button to accept the setting.  
SETBACK FEATURE: The setback feature is similar to both a Temperature  
Override and a Temperature Hold, in that both are used to maintain a fixed set  
temperature instead of following a programmed daily routine. A Setback can be  
considered the same as a Temperature Override, which can last for a longer  
duration that you can adjust from 1-12 hours, or 1-30 days. By default, when a  
Setback is activated in Heat mode, the set temperature used will be 5F (3C)  
degrees lower than the current set temp. For Cool mode, the set temperature  
used will be 5F (3C) degrees higher than the current set temp.  
TO START A SETBACK: Ensure that the System Mode switch is in either the Heat  
or Cool position, and that the Set Slider is in the RUN position. Press and hold  
the SETBACK button for at least 2 seconds. The screen will change and show the  
words “HOURS LEFT” and “OVERRIDE”, along with two digits. Use the UP/DOWN  
buttons to set the duration for how long you would like to maintain a fixed set  
temperature (from 1 to 12 hours). If you would like to set the duration for longer  
than 12 hours, keep pressing the UP button. The display will change from  
“HOURS LEFT” to “DAYS LEFT”, with an available duration of 1 to 30 days. Once  
your desired Setback duration is shown on the screen, you can either wait for the  
screen to advance forward on its own, or press the NEXT button (behind the door)  
one time to jump ahead rapidly. Now use the UP/DOWN buttons to select your  
desired set temperature that will be used for the Setback duration. Just like the  
previous step, you can either wait for the screen to advance on its own, or press  
the NEXT button to advance and return to the Normal Run screen.  
TO CANCEL A SETBACK: While in the Normal Run screen, press and hold the  
SETBACK button for at least 2 seconds. The word “OVERRIDE” will disappear  
from the screen and the Setback will be cancelled. Moving the System Mode  
switch or Set Slide switch, will also cancel a Setback.  
TEMPERATURE LIMIT STOPS: There are two independent set temperature limit  
stops: a maximum heat set temperature, and a minimum cool set temperature.  
These stops do not prevent a user from performing normal actions like  
Temperature Override or Hold. The Heat Limit Stop prevents the set temperature  
from being adjusted higher than the heat limit setting. The Cool Limit Stop  
prevents the set temperature from being adjusted lower than the cool limit  
setting. Each of these temperature stops is user adjustable in one-degree  
KEYPAD LOCKOUT: You can lock the front panel buttons to prevent unauthorized  
tampering of your thermostat settings.  
GRAPHICAL AIR FILTER MONITOR: In most systems that use a blower fan and air  
ducts, there is an air filter that is either replaceable or requires cleaning. The  
filter is usually located in the air handler, where the blower fan is. This  
thermostat feature assists you with keeping track of proper maintenance and/or  
periodic replacement intervals for your system’s filter.  
The Graphical Filter Monitor displays a visual bar graph in the center of the  
screen, which shows the amount of air filter life remaining (in % percent), since  
the last time the air filter timer has been reset. Each dot in the filter bar graph  
equals 10 percent (example: 4 dots shown means 40 percent filter life  
remaining). This feature is for information purposes only, and does not affect the  
operation of your heating or cooling equipment, or the thermostat. When the  
filter usage duration has completly expired, the vertical filter bar graph will be  
empty, and the word “FILTER” will flash on the screen.  
TO SET THE AIR FILTER DURATION: Move the Set Slide switch to the “AIR FILTER”  
position. The words “SET DAYS” will be shown on the screen, along with the  
word “FILTER” and 2-3 characters at the top right corner of the display. Press  
either of the UP/DOWN buttons to select the desired filter duration (in days) from  
the following choices: OFF, 30, 60, 90, 120, 180, or 365. If the filter duration  
value is set to “OFF”, then the Air Filter Monitor will be completely disabled.  
Return the Set Slide switch to the RUN position when you are finished.  
TO RESET THE FILTER USAGE COUNTER: Move the Set Slide switch to the “AIR  
FILTER” position. The three small digits at the bottom of the screen tell you the  
quantity of filter days remaining. Pressing the NEXT button will toggle the  
display between showing the days remaining as a number, or a graphical  
precentage remaining using the vertical bar graph. Press both the UP and DOWN  
buttons together at the same time, and the usage counter will return to the  
beginning of the value that it originally started counting from. Refer to the  
previous paragraph, should you wish to change the starting value for the filter  
monitor. Return the Set Slide switch to the RUN position when you are finished.  
HARDWARE RESET: The Hardware Reset button (labeled “HW  
RST”) is a small round push button that is located in the  
middle of the circuit board, just below the battery holder.  
Pressing this button will cause the LCD display screen to  
become fully populated, the heating and cooling load relays to  
cycle off, and will perform an internal system check of the  
thermostat components. If your thermostat appears to be acting in an erratic  
manner, pressing the Hardware Reset button may remedy this behavior. The  
temperature programs are not erased when a hardware reset is performed,  
however the clock will have to be changed to match the current day and time.  
SOFTWARE RESET: A Software Reset is used to erase ALL heating and cooling  
temperature programs, and to return all user-adjustable software settings back  
to their original factory default values. To perform a Software Reset, first ensure  
that the thermostat’s Keypad Lockout is not enabled and then move the System  
Mode switch to the OFF position. Press and hold the UP, DOWN, and NEXT  
buttons all together for at least 5 seconds. The LCD display screen will become  
fully populated (let go of buttons at this point), and than return to normal. The  
clock will have to be changed to match the current day and time.  
COMPRESSOR PROTECTION BYPASS: This optional feature permits the installer  
or service technician to temporarily disable the built in compressor protection  
delays. This is most useful for diagnosing and testing the heating and cooling  
systems after installation is complete, and should not be used during normal  
operation. To activate this feature, press and hold both the NEXT and HOLD  
buttons, while also perform a single press of the Hardware Reset button (the LCD  
display screen will become fully populated). Continue to hold the NEXT and  
HOLD buttons until the LCD display screen returns to normal. All compressor  
protection delays (in all modes of operation) will be disabled for 5 minutes. After  
the 5-minute duration has expired, the thermostat will return to normal operation  
This thermostat is powered by two “AA” Alkaline batteries. The batteries should  
be replaced AT LEAST once per year to ensure reliable operation (or sooner if  
“LO BATT” appears in the display screen). The batteries are located on the back  
of the thermostat’s circuit board. The front portion of the thermostat can be  
removed from the back half by using the tabs on the top edge of the thermostat  
When installing new batteries, we recommend using only brand new Energizer®  
or DURACELL®, “AA” size alkaline batteries. Please observe the polarity  
markings shown in the battery compartment to ensure proper installation. When  
finished, line up the front of the thermostat to the base, and firmly press together  
to securely latch the front and back halves together properly.  
BATTERY GRAPHIC: Anytime that batteries are  
physically present in the thermostat, there will be  
a visual indication of the remaining battery life  
available on the thermostat’s display screen.  
When brand new batteries are installed in the  
battery compartment, this graphic should indicate  
full battery life remaining with all bars present.  
Over time, as the battery life decreases to the  
point of having only 1 bar left, the Temperature  
and Clock digits will start to alternate between  
showing their normal content, and the words “LO  
BATT”. At this point the batteries will need to be  
replaced as soon as practical to avoid uninterrupted operation of your heating  
and/or cooling system. In most cases, the thermostat will be capable of  
providing you approximately two months of normal operation once the point of 1  
bar left has been reached, and the screen shows the words “LO BATT”.  
If you have any problems installing or using this thermostat, please carefully and  
thoroughly review the instruction manual. If you require assistance, please  
contact our Technical Assistance department at 856-234-8803 during regular  
business hours between 8:00AM and 4:30PM Eastern Standard Time, Monday  
through Friday. You can also receive technical assistance online anytime day or  
guides, answers to the most common technical questions, and also permits you  
to email your questions to our technical support staff at your convenience.  
If this unit fails because of defects in materials or workmanship within three  
years of the date of original purchase, LUX will, at its option, repair or replace it.  
This warranty does not cover damage by accident, misuse, or failure to follow  
installation instructions. Implied warranties are limited in duration to three years  
from the date of original purchase. Some states do not allow limitations on how  
long an implied warranty lasts, so the above limitation may not apply to you.  
Please return malfunctioning or defective units to the location from which the  
purchase was made, along with proof of purchase. Please refer to “TECHNICAL  
ASSISTANCE” before returning thermostat. Purchaser assumes all risks and  
liability for incidental and consequential damage resulting from installation and  
use of this unit. Some states do not allow the exclusion of incidental or  
consequential damages, so the above exclusion may not apply to you. This  
warranty gives you specific legal rights and you may also have other rights,  
which vary from state to state. Applicable in the U.S.A. and Canada only.  
Mercury is considered to be a hazardous material. If this product is replacing a  
thermostat that contains mercury in a sealed tube, contact your local waste  
management authority for instructions regarding recycling and proper disposal.  
It may be unlawful in your state to place it in the trash.  
Mt. Laurel, New Jersey 08054, USA