Home

href="
1F81-51  
Programmable Electronic  
Digital Multi-stage Thermostat  
INSTALLATION AND  
WHITE-RODGERS  
OPERATION INSTRUCTIONS  
Operator: Save these instructions for future use!  
FAILURE TO READ AND FOLLOW ALL INSTRUCTIONS CAREFULLY  
BEFORE INSTALLING OR OPERATING THIS CONTROL COULD CAUSE  
PERSONAL INJURY AND/OR PROPERTY DAMAGE.  
DESCRIPTION  
Your new White-Rodgers 5-Day/2-Day Digital Multi-stage Ther-  
mostat uses the technology of a solid-state microcomputer to  
provideprecisetime/temperaturecontrol.Thisthermostatoffers  
you the flexibility to design heating and cooling programs that fit  
your needs.  
• Preprogrammed temperature control  
• LCD continuously displays set point, and alternately dis-  
plays time and room temperature  
• Temperature override until next program period  
• Manual program override (HOLD temperature)  
°F/°C convertibility  
Features:  
• Temperature range 45° to 90°F  
• Separate 5-day (weekday) and 2-day (weekend) programming  
with four separate time/temperature periods per program  
• Two-stage heat/two-stage cool  
• Simultaneous heat and cool program storage  
• Armchair Programming Capability  
• Optional C terminal (dual power option)  
PRECAUTIONS  
CAUTION  
Thisthermostatisintendedforusewitha24-voltsystem;donot  
use this thermostat with a millivolt or line voltage system. If in  
doubt about whether your wiring is millivolt, line, or low voltage,  
have it inspected by a qualified heating and air conditioning  
contractor or electrician.  
!
To prevent electrical shock and/or equipment damage  
disconnect electric power to system at main fuse or  
circuit breaker box until installation is complete.  
Do not exceed the specification ratings.  
WARNING  
!
Allwiringmustconformtolocalandnationalelectricalcodesand  
ordinances.  
Do not use on circuits exceeding specified voltage.  
Higher voltage will damage control and could cause  
shock or fire hazard.  
This control is a precision instrument, and should be handled  
carefully. Roughhandlingordistortingcomponentscouldcause  
the control to malfunction.  
Do not short out terminals on gas valve or primary  
control to test. Short or incorrect wiring will damage  
thermostat and could cause personal injury and/or  
property damage.  
SPECIFICATIONS  
ELECTRICAL DATA  
APPLICATIONS  
Electrical Rating:  
For use with:  
20 to 30 VAC 50/60 Hz. or D.C.  
0.05 to 1.5 Amps (Load per terminal)  
1.5 Amps Maximum Total Load (All terminals combined)  
• Heat/cool systems with up to two stages heat, two  
stages cool  
DO NOT USE WITH:  
THERMAL DATA  
• Millivolt systems  
Setpoint Temperature Range:  
45°F to 90°F (7°C to 32°C)  
• Systems exceeding 30 VAC and 2.5 amps  
• 3-wire zoned hydronic heating systems  
Operating Ambient Temperature Range:  
32°F to 105°F  
Operating Humidity Range:  
0 to 90% RH (non-condensing)  
Shipping Temperature Range:  
-40°F to 150°F  
WHITE-RODGERS DIVISION  
EMERSON ELECTRIC CO.  
9797 REAVIS ROAD  
PART NO. 37-5854E  
Printed in U.S.A.  
Replaces 37-5854D  
0004  
ST. LOUIS, MISSOURI 63123-5398  
href="
INSTALLATION  
REMOVE OLD THERMOSTAT  
1. Shut off electricity at the main fuse box until installation is  
complete. Ensure that electrical power is disconnected.  
2. Remove the front cover of the old thermostat. With wires  
still attached, remove wall plate from the wall. If the old  
thermostathasawallmountingplate,removethethermostat  
and the wall mounting plate as an assembly.  
W901  
CUT FOR  
LONGER CYCLES  
3. Identifyeachwireattachedtotheoldthermostatusingthe  
labels enclosed with the new thermostat.  
W903  
CUT TO  
DEFEAT EMR  
4. Disconnect the wires from old thermostat one at a time. DO  
GAS ELECTRIC  
NOT LET WIRES FALL BACK INTO THE WALL.  
5. Install new thermostat using the following procedures.  
PRE-INSTALLATION SET-UP  
Figure 1. Back of thermostat base  
1. Remove the packing material from the thermostat.  
Alkaline batteries (3 “AA”–  
install “+” ends to the left)  
2. This thermostat is configured from the factory to operate a  
heat/cool, fossil fuel (gas, oil, etc.), forced air system with up  
to 2 stages of heat and 2 stages of cool. It is configured  
correctly for any system that DOES NOT require the thermo-  
stat to energize the fan on a call for heat.  
Screw anchors  
If your system is an electric heat or heat-pump system that  
REQUIRES the thermostat to turn on the fan on a call for  
heat, locate the GAS/ELECTRIC switch on the back of the  
thermostat (see fig. 1) and switch it to the ELECTRIC  
position. This will allow the thermostat to energize the fan  
immediatelyonacallforheat.Ifyouareunsureiftheheating/  
cooling system requires the thermostat to control the fan,  
contact a qualified heating and air conditioning service  
person.  
C
W2  
G
Reset  
button  
W
Y2  
R
Y
3. Two jumpers are also located on the back of the thermostat,  
so that you may customize the thermostat to meet your  
individual preference (see fig. 1). In most applications, the  
factory jumper settings provide the most comfortable and  
convenient thermostat operation.  
Mounting  
holes  
Figure 2. Thermostat base  
Jumper wire W901 determines how fast the system cycles  
on and off, based on temperature change. As shipped from  
the factory, the thermostat will maintain a very consistent  
room temperature, usually within 1°F of the thermostat  
setting. To achieve a slower on and off cycle, providing a  
slightly wider temperature span, cut and separate jumper  
wire W901.  
INSTALLING THE THERMOSTAT  
1. Gently remove the cover by pulling it straight off the base.  
Forcing or prying on the unit may cause damage to the unit.  
2. Remove the battery tab. With the batteries installed, the  
Armchair Programming feature allows you to program the  
thermostat before installing it on the wall.  
JumperwireW903controlstheEnergyManagementRecov-  
ery (EMR) feature. EMR allows the thermostat to energize  
the heating system up to 30 minutes before the time pro-  
grammed into the thermostat. The thermostat will then  
energize the system to gradually raise the temperature to  
your programmed temperature by using the most efficient  
stage of heat practical.  
3. Pull wires through the hole in the thermostat base and place  
the base over the hole in the wall. Mark mounting hole  
locations on the wall using the base as a template.  
4. Move the base out of the way. Drill mounting holes.  
5. Fasten the base loosely to the wall, as shown in fig. 2, using  
two mounting screws. Place a level against the bottom of the  
base, adjust until level, and then tighten the screws. (Level-  
ing is for appearance only and will not affect thermostat  
operation.) If you are using existing mounting holes, or if the  
holes drilled are too large and do not allow you to tighten the  
base snugly, use plastic screw anchors to secure the base.  
For example, assume that the thermostat is programmed  
overnightto66°Fandtheroomtemperatureis66°. Ifthenext  
programis7AM, 70°F(anincreaseof4°), thethermostatwill  
start the system 30 minutes before 7 AM. If the temperature  
is in the room is within 2°F of your next programmed  
temperature, the thermostat will not start the system early.  
DO NOT clip jumper wire W903 unless you wish to perma-  
nently disable the EMR feature.  
6. Check that the SYSTEM switch is in the OFF position.  
Connect the wires beneath the terminal screws on the base  
using the appropriate wiring diagram (see figs. 3 through 5).  
If LOW BATTERY is displayed, the batteries are low and  
should be replaced with fresh “AA” Energizer® alkaline  
batteries. To replace batteries, install the batteries along the  
top of the base (see fig. 2). The batteries must be installed  
with the positive (+) ends to the left.  
7. Push excess wire into wall and plug hole with a fire-resistant  
material(suchasfiberglassinsulation)topreventdraftsfrom  
affecting thermostat operation.  
(Instructions continue on page 4.)  
2
href="
NOTE  
NOTE  
The following wiring diagrams show typical terminal identifica- Relay contacts shown are thermostatically operated.  
tion and wiring. For proper installation, refer to the original  
manufacturer's instructions.  
* The 24 Volt neutral connection  
to terminal C on the thermostat  
is not required if you replace  
Thermostat  
the batteries once a year with  
Control  
fresh “AA” Energizer® alkaline  
Circuit  
batteries.  
THERMOSTAT  
W2  
C*  
R
Y
Y2  
G
W
SYSTEM  
Heat  
Relay  
Compressor  
Contactor  
Stage 2  
Stage 1  
Hot  
24 VAC  
120 VAC  
Neutral  
Compressor  
Contactor  
Stage 1  
Heat  
Relay  
Fan  
Relay  
TRANSFORMER  
Stage 2  
Figure 3. Typical wiring diagram for single transformer systems  
* The 24 Volt neutral connection  
to terminal C on the thermostat  
is not required if you replace  
the batteries once a year with  
fresh “AA” Energizer® alkaline  
batteries.  
Thermostat  
Control  
Circuit  
THERMOSTAT  
SYSTEM  
CUT AND  
TAPE OFF!  
W2  
C*  
R
Y
Y2  
G
W
Hot  
Heat  
Relay  
Compressor  
Contactor  
Stage 2  
120 VAC  
24 VAC  
Stage 1  
Hot  
Neutral  
24 VAC  
120 VAC  
TRANSFORMER  
Compressor  
Contactor  
Stage 1  
Heat  
Relay  
Neutral  
TRANSFORMER  
Fan  
Relay  
Stage 2  
TWO COMMONS MUST  
BE JUMPERED TOGETHER!  
Figure 4. Typical wiring diagram for two-transformer systems with NO safety circuits  
* The 24 Volt neutral connection  
Thermostat  
to terminal C on the thermostat  
Control  
is not required if you replace  
Circuit  
the batteries once a year with  
fresh “AA” Energizer® alkaline  
THERMOSTAT  
SYSTEM  
batteries.  
W2  
C*  
R
Y
Y2  
G
W
Heat  
Relay  
Compressor  
Contactor  
Stage 2  
Limit or  
Safety  
Switches  
Stage 1  
Limit or  
Safety  
Switches  
Hot  
24 VAC  
120 VAC  
Neutral  
Compressor  
Contactor  
Stage 1  
Heat  
Relay  
Fan  
24 VAC  
Accessory  
Relay N.O.  
Contact  
HEATING  
TRANSFORMER  
Relay  
Stage 2  
Common  
Limit or  
Safety  
Switches  
Limit or  
Safety  
Switches  
Hot  
TWO COMMONS MUST  
BE JUMPERED TOGETHER!  
24 VAC  
120 VAC  
Common  
Neutral  
COOLING  
TRANSFORMER  
Figure 5. Typical wiring diagram for two-transformer systems with safety circuits in BOTH systems  
3
href="
Ifthefanisrunningbutthecompressorisnotrunningandthe  
word COOL is flashing, the compressor lockout feature is  
operating (see Lockout Bypass Option to temporarily  
override the compressor lockout feature during testing).  
CHECK THERMOSTAT OPERATION  
NOTE  
If at any time during testing, your system does not operate  
properly, contact a qualified serviceperson.  
3. Press  
toadjusttemperaturesettingaboveroomtempera-  
ture. The cooling system should stop operating.  
Fan Operation  
NOTE  
1. Turn on power to the system.  
During normal operation, the second stage of heat or cool may  
take 15 to 30 minutes to turn on. The delay varies depending on  
theperformanceofthefirststage.Typicallythesecondstagewill  
comeonsoonerinmoresevereweather,whileinmilderweather  
it will take longer. There is no adjustment to this feature, as it is  
designed to maximize both comfort and efficiency.  
2. Move SYSTEM switch to OFF position.  
3. MoveFANswitchtoON.Theblowershouldbegintooperate.  
4. Move FAN switch to AUTO position. The blower should stop  
within a short period of time.  
Heating System  
1. Move SYSTEM switch to HEAT position  
LOCKOUT BYPASS OPTION  
2. Press  
toadjustthermostatsettingto90° andholdforfive  
seconds. Both stages of the heating system should begin to  
operate within five seconds.  
FOR QUALIFIED SERVICE TECHNICIANS’ USE  
ONLY.OPERATORSSHOULDNOTUSETHISFEA-  
TURE DUE TO POSSIBILITY OF EQUIPMENT OR  
PROPERTY DAMAGE, OR PERSONAL INJURY.  
3. Press  
toadjusttemperaturesettingbelowroomtempera-  
ture. The auxiliary heating system will stop immediately and  
the first stage will stop within three to four minutes.  
COMPRESSOR SHORT TERM  
CYCLE PROTECTION  
Cooling System  
CAUTION  
!
During normal operation, this thermostat has a built-  
in short term (5-minute) time delay. During this 5-  
minute period, the thermostat will lock out the com-  
pressortoallowheadpressuretostabilize. Ifyouwant  
tooverridethisfeaturewhiletestingthermostatopera-  
Topreventcompressorand/orpropertydamage, ifthe  
outdoor temperature is below 50°F, DO NOT operate  
the cooling system.  
1. Move SYSTEM switch to COOL position.  
tion, simply press and buttons at the same time.  
2. Press  
toadjustthermostatsettingto45° andholdforfive  
seconds. The blower should come on immediately on high  
speed, followed by cold air circulation. Both stages of the  
cooling system should begin to operate (if you have a two-  
stage cooling system).  
DO NOT USE THE LOCKOUT BYPASS OPTION  
UNLESSTHECOMPRESSOROILHEATERSHAVE  
BEEN OPERATIONAL FOR 6 HOURS AND THE  
SYSTEM HAS NOT BEEN OPERATIONAL FOR AT  
LEAST 5 MINUTES.  
4
href="
OPERATION  
Before you begin programming your thermostat, you should be  
familiarwithitsfeaturesandwiththedisplayandthelocationand  
operation of the thermostat buttons. Your thermostat consists of  
two parts: the thermostat cover and the base. To remove the  
cover, gently pull it straight out from the base. To replace the  
cover, line up the cover with the base and press gently until the  
cover snaps onto the base.  
1
2
THE THERMOSTAT BASE  
SET TIME VIEW PRGM RUN PRGM HOLD TEMP  
FAN ON  
AUTO  
SYSTEM  
Other than  
and  
, the following buttons and switches are  
COOL-OFF-HEAT  
located behind the door on the bottom of the thermostat cover  
(see fig. 6). Pull the door down to open it.  
The Thermostat Buttons and Switches  
3
4
5
6
7
8
9
(Red arrow) Raises temperature setting.  
(Blue arrow) Lowers temperature setting.  
SET TIME button.  
1
2
3
4
5
6
7
8
9
10  
MO TU WE TH FR  
AM  
SA SU  
HEAT 1+2  
11  
HOLD COOL 1+2  
VIEW PRGM (program) button.  
RUN PRGM (program) button.  
HOLD TEMPerature button.  
12  
11 13 10  
Figure 6. Thermostat display, buttons, and switches  
HOLD TEMPERATURE — The thermostat can hold any  
temperaturewithinitsrangeforanindefiniteperiod, without  
reverting to the programmed temperature. Press HOLD  
TEMP button. HOLD will be displayed. Then choose the  
FAN switch (ON, AUTO).  
SYSTEM switch (COOL, OFF, HEAT).  
The Display  
desired hold temperature by pressing  
or  
. The ther-  
mostat will hold the room temperature at the selected  
setting until you press RUN PRGM button to start program  
operation again.  
Indicates day of the week.  
9
HEATisdisplayedwhentheSYSTEMswitchisintheHEAT  
10  
°F/°C CONVERTIBILITY — Press SET TIME and HOLD  
TEMP buttons until the temperature display is in Celsius  
(°C). To display Fahrenheit (°F), repeat the process.  
position. COOL is displayed when the SYSTEM switch is in  
the COOL position. COOL is displayed (flashing) when the  
compressor is in lockout mode.  
TEMPERATURE DISPLAY ADJUSTMENT — Your new  
thermostathasbeenaccuratelysetinourfactory.However,  
if you wish, you may adjust your new thermostat tempera-  
ture display to match your old thermostat. This can be  
accomplished (within a ±4°F range) as follows:  
Alternately displays current time and room temperature.  
11  
12  
Displays currently programmed set temperature (this is  
blank when SYSTEM switch is in the OFF position).  
1. Press VIEW PRGM and HOLD TEMP buttons at the  
same time.  
The word HOLD is displayed when the thermostat is in the  
13  
HOLD mode.  
2. Press  
or  
to adjust the displayed temperature to  
OPERATING FEATURES  
Now that you are familiar with the thermostat buttons and  
display, read the following information to learn about the many  
features of the thermostat.  
your desired setting.  
3. Press RUN PRGM to resume normal program opera-  
tion.  
PROGRAMMING YOUR THERMOSTAT  
SIMULTANEOUS HEATING/COOLING PROGRAM  
STORAGEWhenprogramming,youcanenterbothyour  
heating and cooling programs at the same time. There is no  
need to reprogram the thermostat at the beginning of each  
season.  
Now you are ready to program your thermostat. This section will  
help you plan your thermostat’s program to meet your needs.  
For maximum comfort and efficiency, keep the following guide-  
lines in mind when planning your program.  
• When heating (cooling) your building, program the tem-  
peratures to be cooler (warmer) when the building is vacant  
or during periods of low activity.  
TEMPERATURE OVERRIDE — Press  
or  
until the  
display shows the temperature you want. The thermostat  
will override current programming and keep the room  
temperature at the selected temperature until the next  
program period begins. Then the thermostat will automati-  
cally revert to the program.  
• During early morning hours, the need for cooling is usually  
minimal.  
(Instructions continue on page 6.)  
5
href="
Look at the factory preprogrammed times and temperatures 3. Press SET TIME once. The display window will show the  
shown below. If this program will suit your needs, simply press the  
RUN PRGM button to begin running the factory preset program.  
minutes only.  
EXAMPLE:  
FACTORY PREPROGRAMMING  
Cooling Program for  
Heating Program for  
ALL days of the Week:  
ALL Days of the Week:  
TEMP  
PERIOD  
TIME  
TEMP  
PERIOD  
1st  
2nd  
3rd  
4th  
TIME  
4. Press and hold either  
minutes.  
or  
until you reach the correct  
70°F  
62°F  
70°F  
62°F  
1st  
2nd  
3rd  
4th  
6:00 AM  
8:00 AM  
5:00 PM  
10:00 PM  
6:00 AM  
8:00 AM  
5:00 PM  
10:00 PM  
78°F  
85°F  
78°F  
82°F  
5. Press SET TIME once. The display will show the day of the  
week.  
If you want to change the preprogrammed times and tempera-  
tures, follow these steps.  
6. Press  
or  
until you reach the current day of the week.  
Determine the time periods and heating and cooling tempera-  
tures for your weekday and weekend programs. You must  
program four periods for both the weekday and weekend pro-  
7. Press RUN PRGM once. The display will show the correct  
time and room temperature alternately.  
gram. However, you may use the same heating and cooling Enter Heating Program  
temperatures for consecutive time periods. You can choose  
1. If you want to change the display from Fahrenheit to Celsius  
start times, heating temperatures, and cooling temperatures  
independently for both weekday and weekend programs (for  
example, you may select 5:00 AM and 70° as the weekday 1st  
period heating start time and temperature, and also choose  
7:00 AM and 76° as the weekday 1st period cooling start time  
and temperature).  
(or vice-versa), press SET TIME and HOLD TEMP at the  
same time.  
2. Move the SYSTEM switch to HEAT.  
3. Press VIEW PRGM once. “MO TU WE TH FR” (indicating  
weekday program) will be displayed. Also displayed are  
the currently programmed start time for the 1st heating  
period and the currently programmed temperature (flash-  
ing).  
Usethetableatthebottomofthepagetoplanyourprogramtime  
periods,andthetemperaturesyouwantduringeachperiod.You  
may also want to look at the sample program table to get an idea  
of how the thermostat can be programmed.  
MO TU WE TH FR  
AM  
EXAMPLE:  
Entering Your Program  
This display window shows that for the 1st weekday period,  
the start time is 6:00 AM, and 70° is the programmed  
temperature(thisexamplereflectsfactorypreprogramming).  
Follow these steps to enter the heating and cooling programs  
you have selected.  
Set Current Time and Day  
4. Press  
or  
to change the displayed temperature to your  
selected temperature for the 1st heating program period.  
5. Press SET TIME once (the programmed time will flash).  
1. Press SET TIME button once. The display will show the hour  
only.  
Press  
or  
untilyourselectedtimeisdisplayed. Thetime  
PM  
EXAMPLE:  
will change in 15 minute increments. When your selected  
time is displayed, press SET TIME again to return to the  
change temperature mode.  
2. Press and hold either  
or  
until you reach the correct  
6. Press VIEW PRGM once. The currently programmed start  
time and setpoint temperature for the 2nd heating program  
period will be displayed.  
hour and AM/PM designation (AM begins at midnight; PM  
begins at noon).  
SAMPLE  
Heating/Cooling Schedule Plan  
Heating/Cooling Schedule Plan  
WEEKEND (2 DAY)  
WEEKDAY (5 DAY)  
WEEKEND (2 DAY)  
WEEKDAY (5 DAY)  
Start  
Time  
Start  
Time  
Start  
Time  
Start  
Time  
Period  
Temperature  
Temperature  
Period  
Temperature  
Temperature  
1ST HEAT  
1ST HEAT  
5:30 AM  
70°F  
7:00 AM  
11:00 AM  
6:00 PM  
11:30 PM  
7:00 AM  
12:30 PM  
6:00 PM  
11:30 PM  
70°F  
2ND HEAT  
3RD HEAT  
4TH HEAT  
1ST COOL  
2ND COOL  
3RD COOL  
4TH COOL  
2ND HEAT 8:00 AM  
3RD HEAT 5:00 PM  
4TH HEAT 10:30 PM  
1ST COOL 6:30 AM  
2ND COOL 2:00 PM  
3RD COOL 5:00 PM  
4TH COOL 10:30 PM  
65°F  
70°F  
65°F  
76°F  
78°F  
72°F  
78°F  
70°F  
70°F  
65°F  
76°F  
74°F  
72°F  
78°F  
6
href="
7. Repeat steps 4 and 5 to select the start time and heating  
temperature for the 2nd heating program period.  
CHECK YOUR PROGRAMMING  
Follow these steps to check your thermostat programming one  
final time before beginning thermostat operation.  
8. Repeatsteps4through6forthe3rdand4thheatingprogram  
periods. Weekday heating programs are now complete.  
1. Move SYSTEM switch to HEAT position.  
9. Press VIEW PRGM once. “SA SU” (indicating weekend  
program) will be displayed, along with the start time for the  
1st heating period and the currently programmed tempera-  
ture.  
2. Press VIEW PRGM to view the 1st weekday heating period  
time and temperature. Each time you press VIEW PRGM,  
the next heating period time and temperature will be dis-  
played in sequence for weekday, then weekend program  
periods(youmaychangeanytimeortemperatureduringthis  
procedure).  
10.Repeat steps 4 through 8 to complete weekend heating  
programming.  
11.When you have completed entering your heating program,  
press RUN PRGM.  
3. Press RUN PRGM.  
4. Move SYSTEM switch to COOL position.  
5. Repeat step 2 to check cooling temperatures.  
6. Press RUN PRGM to begin program operation.  
Enter Cooling Program  
CAUTION  
!
YOUR THERMOSTAT IS NOW COMPLETELY PRO-  
GRAMMED AND READY TO AUTOMATICALLY PROVIDE  
MAXIMUM COMFORT AND EFFICIENCY!  
If the outside temperature is below 50°F, disconnect  
power to the cooling system before programming.  
Energizing the air conditioner compressor during  
cold weather may cause personal injury or property  
damage.  
TROUBLESHOOTING  
1. Move SYSTEM switch to COOL position.  
If your thermostat’s display is frozen, blank or displaying incor-  
rectly, the thermostat may have been affected by static dis-  
charge or voltage variations. If this happens, press the RESET  
button (see fig. 2, page 2 for the location of the button). Pressing  
the RESET button will clear all user programming. The thermo-  
stat will revert to factory preprogramming. You will need to reset  
the time and, if desired, reprogram the thermostat to your  
selected program. If pressing the RESET button does not  
correct the problem, contact a qualified service technician.  
2. Follow the procedure for entering your heating program,  
using your selected cooling times and temperatures.  
For optimum performance, we recommend replacing batteries  
once a year with fresh “AA” Energizer® alkaline batteries.  
7