White Rodgers EMERSON 1E78 User Manual

CONTENTS

Installation Instructions for

Heating & Air Conditioning

1E78

5/2 Day Programmable Thermostat

Y OUR THERMOST AT REPLACES

Typical System Compatibility Chart 1E78

Standard Heat Only Two Wire Gas or Oil Fired Systems (24 volt) Yes
Electronic Ignition Heat Only Two Wire Systems (24 volt) Yes
Electronic Ignition Heat Only Gas or Oil Fired Systems (24 volt) Yes
Standard Heat/Cool Systems (24 volt) Yes
Heat/Cool Systems Electric Heat (24 volt) Yes
Heat Only Electric Heat Systems (24 volt) Yes
Cool Only Systems (24 volt) Yes
Heat Pump Systems (No Aux or Emergency Heat) Yes
Hot Water Zone Heat Only (Two Wire) Systems Yes
Hot Water Zone Heat Only (Three Wire) Systems No
Line Voltage Heating or Baseboard 110/240 Volt Systems No
Millivolt Systems Floor or Wall Furnaces Yes
12 VDC Mobile Home Application Yes
Multistage Systems No
Systems Exceding 30VAC, 1.5 Amp No

Preparations.................................................. 1

Thermostat Details ........................................ 1

Removing Old Thermostat ............................ 1

Mounting and Wiring ..................................... 2

Check Thermostat Operation........................ 3

Programming your Thermostat ..................... 4

Specifications ................................................ 6

Troubleshooting ............................................ 6

PREPARATIONS

1

Assemble tools required as shown below.

FLAT BLADE SCREWDRIVER

HAND OR POWER
DRILL WITH 3/16 INCH
DRILL BIT, IF NEEDED

WIRE CUTTER/STRIPPER

Failure to follow and read all instructions carefully
before installing or operating this control could cause
personal injury and/or property damage

THERMOSTAT DETAILS

2

Mounting

Hole

RC

GRH

W

YOB

Base

Mounting

Hole

W903 - clip to disable EMR feature
W904 - clip for Celcius display
W905 - clip for hydronic system

Figure 1. Thermostat

ELEC GAS

Back of

Thermostat Body

W905
W904
W903

Elec/Gas

Switch

REMOVING OLD THERMOSTAT

3

CAUTION

!

To prevent electrical shock and/or equipment damage,
disconnect electrical power to the system at the main
fuse or circuit breaker until installation is complete.

Before removing wires from old thermostat’s switching subbase,

label each wire with the terminal designation it was removed from.

1. Remove Old Thermostat: A standard heat/cool thermostat

consists of three basic parts:
a. The cover, which may be either a snap-on or hinge type.
b. The base, which is removed by loosening all captive screws.
c. The switching subbase, which is removed by unscrewing

the mounting screws that hold it on the wall or adaptor plate.

2. Shut off electricity at the main fuse box until installation is
complete. Ensure that electrical power is disconnected.

3. Remove the front cover of the old thermostat. With wires still
attached, remove wall plate from the wall. If the old thermostat

has a wall mounting plate, remove the thermostat and the wall
mounting plate as an assembly.

4. Identify each wire attached to the old thermostat.

5. Disconnect the wires from the old thermostat one at a time. DO
NOT LET WIRES FALL BACK INTO THE WALL.

6. Install new thermostat using the following procedures.

White-Rodgers is a division

of Emerson Electric Co.

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PART NO. 37-6542B

Replaces 37-6542A

0434

REMOVING OLD THERMOSTAT

3

CONTINUED FROM FIRST PAGE

ATTENTION! This product does not contain mercury. How­ever, this product may replace a unit which contains mercury.

Do not open mercury cells. If a cell becomes damaged, do not
touch any spilled mercury. Wearing non-absorbent gloves, take
up the spilled mercury and place into a container which can be
sealed. If a cell becomes damaged, the unit should be discarded.

Mercury must not be discarded in household trash. When the unit
this product is replacing is to be discarded, place in a suitable
container and return to White-Rodgers at 2895 Harrison Street,
Batesville, AR, 72501 for proper disposal.

MOUNTING AND WIRING

4

CAUTION

!

Take care when securing and routing wires so they do
not short to adjacent terminals or rear of thermostat.
Personal injury and/or property damage may occur.

TERMINAL CROSS REFERENCE CHART

New Thermostat

Terminal Designation

RH
RC

G

W

Y

Other Manufacturers’
Terminal Designation

4

RH

M

R

R

V

G

G

F

W

W

H

Y

Y

C

**

R5

R

-

-

G

G

4

W

Y6

Y

WARNING

!

Do not use on circuits exceeding specified voltage.
Higher voltage will damage control and could cause
shock or fire hazard.

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.

Thermostat installation and all components of the sys­tem shall conform to Class II circuits per the NEC code.

Electric Heat or Single-Stage

Heat Pump Systems

This thermostat is configured from the factory to operate a heat/
cool, fossil fuel (gas, oil, etc.), forced air system. It is configured
correctly for any system that DOES NOT require the thermostat
to energize the fan on a call for heat. If your system is an electric
or heat-pump system that REQUIRES the thermostat to turn on
the fan on a call for heat, locate the GAS/ELECTRIC switch (see
fig. 1) and switch it to the ELECTRIC position. This will allow the
thermostat to energize the fan immediately on a call for heat. If you
are unsure if the heating/cooling system requires the thermostat
to control the fan, contact a qualified heating and air conditioning
service person.

Hydronic (Hot Water or Steam)

Heating Systems

This thermostat is set to operate properly with a forced-air heating
system. If you have a hydronic heating system (a system that
heats with hot water or steam), you must set the thermostat to
operate properly with your system.

The factory default setting is forced air heat. Clipping jumper
W905 on the circuit board will produce a longer heating cycle
which is normally for hot water or steam (hydronic) systems. Both
settings produce a very accurate temperature control and can be
set to your personal preference. As received, the thermostat
cycles the system just under 1˚F. With W905 clipped, the system
cycles at approximately 1.5˚F.

* These are four-wire, single-transformer systems.
Factory installed jumper wire between the RH
and RC terminals must remain in place.

Energy Management Recovery (EMR)

This thermostat is set to operate with EMR. This causes the
thermostat to start the heating or cooling system early to have
the room temperature reach the program setpoint at the time
the period is to start.

To disable EMR, clip jumper W903 (see Fig. 1).

Attach Thermostat Base to Wall

1. Remove the packing material from the thermostat. Gently pull
the thermostat body straight off the base. Forcing or prying on
the thermostat will cause damage to the unit. If necessary,
move the electric heat switch (see ELECTRIC HEAT SYS-
TEMS, above).

2. Connect wires beneath terminal screws on base using appro­priate wiring schematic (see figs. 2 through 7).

3. Place base over hole in wall and mark mounting hole locations
on wall using base as a template.

4. Move base out of the way. Drill mounting holes.

5. Fasten base loosely to wall, as shown in fig. 1, using two
mounting screws. Adjust until level, and then tighten screws.
(Leveling is for appearance only and will not affect thermostat
operation.) If you are using existing mounting holes, or if holes
drilled are too large and do not allow you to tighten base
snugly, use plastic screw anchors to secure subbase.

6. Push excess wire into wall and plug hole with a fire-resistant
material (such as fiberglass insulation) to prevent drafts from
affecting thermostat operation.

Battery Location

This thermostat requires 2 “AAA” alkaline batteries to operate.
If “LO BATTERY” appears on the display, the batteries are low
and should be replaced with fresh “AAA” Energizer® alkaline
batteries. The batteries are located on the back of the thermostat
body (see fig. 1).

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MOUNTING AND WIRING

4

CONTINUED FROM SECOND PAGE

Y

Y

Cooling
System

NOTE

Y

Cooling
System

G W

Fan

Relay

G W

Fan

Relay

G W

Fan

Relay

OB

NOTE

For 2-wire Heat only,
attach to RH and W

Figure 2. Typical wiring diagram for

heat only, 3-wire, single transformer systems

Figure 3. Typical wiring diagram for

cool only, 3-wire, single transformer systems

RED jumper wire (provided with thermostat) must be

connected between thermostat RH and RC terminals
for proper thermostat operation with this system.

OB

Figure 4. Typical wiring diagram for

heat/cool, 4-wire, single transformer systems

Heating
System

Heating
System

RCOB

RC

JUMPER

WIRE

24 VAC

JUMPER

WIRE

RH

24 VAC

TRANSFORMER

THERMOSTAT

RH

TRANSFORMER

JUMPER

WIRE

RH

RC

24 VAC

TRANSFORMER

THERMOSTAT

SYSTEM

120 VAC

SYSTEM

Hot

120 VAC

Neutral

THERMOSTAT

SYSTEM

Hot

120 VAC

Neutral

Hot

Neutral

OB

Y

Cooling
System

G W

Fan

Relay

Heating
System

THERMOSTAT

RH

RC

SYSTEM

24 VAC

HEATING

TRANSFORMER

24 VAC

COOLING TRANSFORMER

Hot

120 VAC

Neutral

Hot

120 VAC

Neutral

Figure 5. Typical wiring diagram for

heat/cool, 5-wire, two-transformer systems

G W

Fan

JUMPER

WIRE

RCOB

24 VAC

THERMOSTAT

RH

SYSTEM

TRANSFORMER

Hot

120 VAC

Neutral

JUMPER

WIRE

Y

Reversing

Compressor

Valve*

Contactor

* Reversing valve is energized when the
system switch is in the COOL position

Relay

Figure 6. Typical wiring diagram for heat pump

with reversing valve energized in COOL

G W

Fan

JUMPER

WIRE

RCOB

24 VAC

THERMOSTAT

RH

SYSTEM

TRANSFORMER

Hot

120 VAC

Neutral

JUMPER

WIRE

Y

Reversing

* Reversing valve is energized when the
system switch is in the HEAT position

Valve*

Compressor

Contactor

Relay

Figure 7. Typical wiring diagram for heat pump

with reversing valve energized in HEAT

CHECK THERMOST A T OPERA TION

5

NOTE

To prevent static discharge problems, touch side of ther­mostat to release static build-up before touching any keys.

If at any time during testing your system does not operate
properly, contact a qualified serviceperson.

Fan Operation

If your system does not have a G terminal connection, skip to
Heating System.

1. Turn on power to the system.

2. Move FAN switch to ON position. The blower should begin to
operate.

3. Move FAN switch to AUTO position. The blower should stop
immediately.

Cooling System

CAUTION

!

To prevent compressor and/or property damage, if the
outdoor temperature is below 50°F, DO NOT operate the
cooling system.

This thermostat has a time delay between cooling cycles to allow
the head pressure in the compressor to stabilize. If the tempera­ture is adjusted to call for cool within 5 minutes of the last cycle the
snowflake icon will blink indicating the thermostat is locked out.
After 3 to 5 minutes, the compressor will start and the snowflake
icon will stop flashing. This helps prevent the compressor from
cycling too quickly and is normal operation for the thermostat.

1. Move SYSTEM switch to COOL position.

2. Press

to adjust thermostat setting below room tempera­ture. The blower should come on immediately on high speed,
followed by cold air circulation

3. Press to adjust temperature setting above room tem­perature. The cooling system should stop operating.

Heating System

1. Move SYSTEM switch to HEAT position. If the heating system
has a standing pilot, be sure to light it.

2. Press to adjust thermostat setting above room tempera­ture. The heating system should begin to operate.

3. Press to adjust temperature setting below room tem­perature. The heating system should stop operating.

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CHECK THERMOST A T OPERA TION

Figure 8. Thermostat display, buttons and switches

5

CONTINUED FROM THIRD PAGE

Before you begin programming your thermostat, you should be
familiar with its features and with the display and the location and
operation of the thermostat buttons. Your thermostat consists of
two parts: the thermostat body and the base. To remove the
body, gently pull it straight out from the base. To replace the body,
line up the body with the base and press gently until the body
snaps onto the base.

The Thermostat Buttons and Switches

1

(Up arrow) Raises temperature setting.
(Down arrow) Lowers temperature setting.

2

3

TIME button.
PRGM (program) button.

4
5

RUN (program) button.

6

HOLD button.

7

FAN switch (ON, AUTO).
SYSTEM switch (COOL, OFF, HEAT).

8

The Display

Indicates day of the week.

9

is displayed when the SYSTEM switch is in the HEAT

10

position.
switch is in the COOL position. is displayed (flashing)

when the compressor is in lockout mode.
Alternately displays current time and temperature.

11

“LO BATTERY” is displayed when the 2 “AAA” batteries are

12

low and should be replaced. Nothing else will be displayed.

13

Displays currently programmed set temperature (this is blank
when SYSTEM switch is in the OFF position).

“HOLD” is displayed when the thermostat is in the HOLD

14

mode.

is displayed (non-flashing) when the SYSTEM

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.

• SIMULTANEOUS HEATING/COOLING PROGRAM STOR­AGE — When programming, you can enter both your heating

and cooling programs at the same time. There is no need to
reprogram the thermostat at the beginning of each season.

• 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 automatically revert to the
program.

• HOLD TEMPERATURE — The thermostat can hold any
temperature within its range for an indefinite period, without
reverting to the programmed temperature. Press HOLD

button. “HOLD” will be displayed. Then choose the desired
temperature by pressing
hold the room temperature at the selected setting until you
press the RUN button to start program operation again.

• ENERGY MANAGEMENT RECOVERY — Energy Manage-
ment Recovery (EMR) causes the thermostat to start heating
or cooling early to make the building temperature reach the
program setpoint at the time you specify. Heating will start 5
minutes early for every 1° of temperature required to reach
setpoint. Cooling will start approximately 15 minutes early for
every 1° because it takes longer to reach temperature.
Clipping W903 jumper will disable EMR.

Example: You select EMR and have your heating pro­grammed to 65° at night and 70° at 7 AM. If the building
temperature is 65° the difference between 65° and 70° is 5°.
Allowing 5 minutes per degree the thermostat setpoint will
change to 70° at 6:35 AM.

• °F/°C CONVERTIBILITY — The factory default setting is
Fahrenheit. Clipping W904 jumper on the circuit board (see
fig. 1) will alter this feature to Celsius temperature setting.

• LOW BATTERY INDICATOR — If the 2 “AAA” alkaline batter­ies are low and should be replaced, the display will be blank
except for “LO BATTERY”. When the batteries are low, press­ing any button will cause the display to operate for ten seconds.
After ten seconds, the display will return to blank except for
“LO BATTERY”. After “LO BATTERY” has been displayed
for 4 weeks, the thermostat will raise the temperature 10
degrees above your setpoint in COOL mode and will drop
temperature 10 degrees below your setpoint in HEAT mode.
You cannot program with low batteries, but you can override
setpoint temperature.

or . The thermostat will

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• TEMPERATURE DISPLAY ADJUSTMENT — Your new
thermostat has been accurately set in our factory. However,
if you wish, you may adjust your new thermostat temperature
display to match your old thermostat. This can be accom­plished (within a ±3° range) as follows:

1. Press PRGM and RUN buttons at the same time.

2. Press

or to adjust the displayed temperature to

your desired setting.

3. Press RUN to resume normal program operation.

• Display Backlight— The display backlight improves display
contrast in low lighting conditions. Selecting backlight ON will
turn the light on for a short period of time after any button is
pressed. Selecting backlight OFF (default) will keep the light
off. Turn the display backlight feature ON as follows:

1. Press TIME and RUN buttons at the same time. The

display will show “d-L” and “OFF” alternately.

2. Press

PROGRAMMING Y OUR THERMOST A T

6

or to change “OFF” to “ON”

This section will help you plan your thermostat’s program to meet
your needs. For maximum comfort and efficiency, keep the
following guidelines in mind when planning your program.

• When heating (cooling) your building, program the tempera­tures to be cooler (warmer) when the building is vacant or
during periods of low activity.

• During early morning hours, the need for cooling is usually
minimal.

Look at the factory preprogrammed times and temperatures shown
below. If this program will suit your needs, simply press the RUN
button to begin running the factory preset program.
If you want to change the preprogrammed times and tempera­tures, follow these steps.
Determine the time periods and temperatures for your weekday
and weekend programs. You must program four periods for both
the weekday and weekend program. However, you may use the
same heating and cooling temperatures for consecutive time
periods. You can choose 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). Use the table at the bottom of the
page to plan your program time periods and the temperatures you
want during each period. You may also want to look at the sample
program table to get an idea of how the thermostat can be
programmed.

Heating/Cooling Schedule Plan (Factory Program)

WEEKDAY (5 DAY)

Period

COOL HEAT

1ST
2ND
3RD
4TH
1ST
2ND
3RD
4TH

Start
Time Temperature

6:00 AM
8:00 AM
5:00 PM
10:00 PM
6:00 AM
8:00 AM
5:00 PM
10:00 PM

SAMPLE

70 F
62 F
70 F
62 F
78 F
85 F
78 F
82 F

WEEKEND (2 DAY)

Start
Time Temperature

6:00 AM
8:00 AM
5:00 PM
10:00 PM
6:00 AM
8:00 AM
5:00 PM
10:00 PM

70 F
62 F
70 F
62 F
78 F
85 F
78 F
82 F

Entering Your Program

Follow these steps to enter the heating and cooling programs you
have selected.

Set Current Time and Day

1. Press TIME button once. The display will show the hour only.

EXAMPLE:

2. Press and hold either or until you reach the correct
hour and AM/PM designation (AM begins at midnight; PM
begins at noon).

3. Press TIME once. The display window will show the minutes only.

EXAMPLE:

4. Press and hold either or until you reach the correct
minutes.

5. Press TIME once. The display will show the day of the week.

6. Press

or until you reach the current day of the week.

7. Press RUN once. The display will show the correct time and
room temperature alternately.

Enter Heating Program

1. Move the SYSTEM switch to HEAT.

2. Press PRGM once. “MO TU WE TH FR” (indicating weekday
program) will appear in the display. Also displayed are the
currently programmed start time for the 1st heating period and
the currently programmed temperature (flashing).

MO TU WE TH FR

EXAMPLE:

This display window shows that for the 1st weekday period,
the start time is 6:00 AM, and 70° is the programmed tempera­ture (this example reflects factory preprogramming).

3. Press
your selected temperature for the 1st heating program period.

4. Press TIME once (the programmed time will flash). Press
change in 15 minute increments. When your selected time is

displayed, press TIME again to return to the change tempera­ture mode.

5. Press PRGM once. The currently programmed start time and
setpoint temperature for the 2nd heating program period will
appear.

Period

COOL

COOL HEAT

or to change the displayed temperature to

or until your selected time appears. The time will

Heating/Cooling Schedule Plan

WEEKDAY (5 DAY)

Start
Time Temperature

1ST
2ND
3RD
4TH
1ST
2ND
3RD
4TH

PM

AM

WEEKEND (2 DAY)

Start
Time Temperature

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PROGRAMMING Y OUR THERMOST AT

6

CONTINUED FROM FIFTH PAGE

6. Repeat steps 4 and 5 to select the start time and heating
temperature for the 2nd heating program period.

7. Repeat steps 4 through 6 for the 3rd and 4th heating program
periods. Weekday heating programs are now complete.

8. Press PRGM once. “SA SU” (indicating weekend program) will
appear in the display, along with the start time for the 1st
heating period and the currently programmed temperature.

9. Repeat steps 4 through 8 to complete weekend heating
programming.

10. When you have completed entering your heating program,
press RUN.

Enter Cooling Program

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.

1. Move SYSTEM switch to COOL position.

2. Follow the procedure for entering your heating program, using
your selected cooling times and temperatures.

SPECIFICATIONS

7

ELECTRICAL DATA
Electrical Rating:

MV to 30 VAC 50/60 Hz. or D.C.

0.05 to 1.0 Amps (Load per terminal)

1.5 Amps Maximum Total Load (All terminals combined)

Check Your Programming

Follow these steps to check your thermostat programming one
final time before beginning thermostat operation.

1. Move SYSTEM switch to HEAT position.

2. Press PRGM to view the 1st weekday heating period time and
temperature. Each time you press PRGM, the next heating
period time and temperature will be displayed in sequence for
weekday, then weekend program periods (you may change
any time or temperature during this procedure).

3. Press RUN.

4. Move SYSTEM switch to COOL position.

5. Repeat step 2 to check cooling temperatures.

6. Press RUN to begin program operation.

YOUR THERMOSTAT IS NOW COMPLETELY PROGRAMMED
AND READY TO AUTOMATICALLY PROVIDE MAXIMUM
COMFORT AND EFFICIENCY!

THERMAL DATA
Setpoint Temperature Range:

45°F to 90°F (7°C to 32°C)

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

TROUBLESHOOTING

8

Reset Operation

If a voltage spike or static discharge blanks out the display or
causes erratic thermostat operation you can reset the thermostat
by pressing , and TIME at the same time. This also
resets the factory defaults. If the thermostat has power, has been

reset and still does not function correctly contact your heating/
cooling service person or place of purchase.

Batteries

For optimum performance, we recommend replacing batteries
once a year with fresh “AAA” Energizer

Symptom Possible Cause Corrective Action

No Heat/No Cool/No Fan 1. Blown fuse or tripped circuit breaker. Replace fuse or reset breaker.
(common problems) 2. Furnace power switch to OFF. Turn switch to ON.

3. Furnace blower compartment door or Replace door panel in proper position to engage
panel loose or not properly installed. safety interlock or door switch.

No Heat 1. Pilot light not lit. Re-light pilot.

2. SYSTEM Switch not set to HEAT. Set SYSTEM Switch to HEAT and raise setpoint

temperature above room temperature.

3. Loose connection to thermostat or system. Verify thermostat and system wires are securely

attached.

4. Furnace Lock-Out Condition. Heat may also Many furnaces have safety devices that shut
be intermittent. down when a lock-out condition occurs. If the

heat works intermittently contact the furnace
manufacturer or local service person for
assistance.

®

alkaline batteries.

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TROUBLESHOOTING

8

Symptom Possible Cause Corrective Action

No Heat (continued) 5. Heating system requires service or Diagonistic: Set SYSTEM Switch to HEAT and raise

thermostat requires replacement. the setpoint above room temperature. Within a few

seconds the thermostat should make a soft click
sound. This sound usually indicates the thermo­stat is operating properly. If the thermostat does
not click, try the reset operation listed above. If the
thermostat does not click after being reset contact
your heating and cooling service person or place
of purchase for a replacement. If the thermostat
clicks, contact the furnace manufacturer or a
service person to verify the heating is operating
correctly.

No Cool 1. SYSTEM Switch not set to COOL. Set SYSTEM Switch to COOL and lower setpoint

temperaturebelow room temperature.

2. Loose connection to thermostat or system. Verify thermostat and system wires are securely
attached.

3. Cooling system requires service or Same procedure as diagnostic for No Heat

thermostat requires replacement. condition except set the thermostat to COOL and

lower the setpoint below the room temperature.
There may be up to a five minute delay before the
thermostat clicks in Cooling.

Heat, Cool or Fan Runs Constantly. 1. Possible short in wiring. Check each wire connection to verify they are not

2. Possible short in thermostat. shorted or touching together. No bare wire should

3. Possible short in heat/cool/fan system. stick out from under terminal screws. Try resetting

4. FAN Switch set to Fan ON. the thermostat as described abov e. If the condition
persists the manufacturer of your system or
service person can instruct you on how to test the
Heat/Cool system for correct operation. If the
system operates correctly, replace the thermostat.

Furnace Cycles Too Fast or Too Slow 1. The location of the thermostat and/or the Digital thermostats normally provide precise
(narrow or wide temperature swing) size of the Heating System may be temperature control and may cycle faster than some

influencing the cycle rate. older mechanical models. A faster cycle rate means

the unit turns on and off more frequently but runs
for a shorter time so there is no increase in energy
use. If you would like to increase the cycle time, clip
Jumper W-905 as mentioned in the instructions for
Hydronic Heating Systems. It is not possible to
shorten the cycle time. If an acceptable cycle rate is
not achieved as received or by clipping W-905
contact a local service person for additional
suggestions.

Cooling Cycles Too Fast or Too Slow 1. The location of the thermostat and the size The cycle rate for cooling is fixed and can not be
(narrow or wide temperature swing) of the Cooling System can influence the adjusted. Contact a local service person for

cycle rate. suggestions.

Thermostat Setting and Thermostat 1. Thermostat thermometer setting requires The thermometer can be adjusted +/- 3 degrees.
Thermometer Disagree adjustment. See Temperature Display Adjustment in the

Operation section.

Thermostat Does Not Follow Program 1. AM or PM set incorrectly in program. Check current clock and program settings

2. AM or PM set incorrectly on the clock. including the AM or PM designations for each

3. Voltage spike or static discharge. time period. If a voltage spike or a static discharge
occurs use the Reset Operation listed above.

Blank Display and/or Keypad 1. Voltage spike or static discharge. Replace batteries and check heat/cool system
Not Responding 2. Battery change required. for proper operation. If a voltage spike occurs use

the Reset Operation listed above.

The Emerson logo is a
trademark and a service mark
of Emerson Electric Co.

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