Honeywell T8511G Thermostat User Manual

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T8511G,R Microelectronic  
Heat Pump Thermostats  
INSTALLATION INSTRUCTIONS  
APPLICATION  
The T8511 Microelectronic Heat Pump Thermostat provides electronic control of 24 Vac two-stage heating and one-stage  
cooling heat pump systems. Refer to Table 1 for a general description of the thermostat. All T8511 Thermostats require a  
common wire to supply power.  
Table 1. Description of T8511 Thermostats.  
Fan  
T8511 Changeover  
System Selection  
Em. Heat-Heat-Off-Auto-Cool On-Auto  
Em. Heat-Heat-Off-Cool On-Auto  
Selection  
Comments  
G
R
Automatic  
Manual  
System and fan selections are by keyboard.  
System and fan selections are by switches.  
MERCURY NOTICE  
If this control is replacing a control that contains  
mercury in a sealed tube, do not place your old  
control in the trash.  
CAUTION  
Electrical Shock or Equipment Damage Hazard.  
Can shock individuals or short equipment  
circuitry.  
Disconnect power supply before installation.  
Contact your local waste management authority for  
instructions regarding recycling and the proper  
disposal of the old thermostat.  
Location  
Install the thermostat about 5 ft (1.5m) above the floor in  
an area with good air circulation at average temperature.  
See Fig. 1.  
INSTALLATION  
Do not install the thermostat where it can be affected by:  
—
—
—
—
—
drafts, or dead spots behind doors and in corners.  
hot or cold air from ducts.  
radiant heat from sun or appliances.  
concealed pipes and chimneys.  
unheated (uncooled) areas such as an outside wall  
behind the thermostat.  
When Installing this Product...  
1.  
Read these instructions carefully. Failure to follow  
the instructions can damage the product or cause a  
hazardous condition.  
2.  
Check the ratings given in the instructions and on  
the product to make sure the product is suitable for  
your application.  
3
.
.
Installer must be a trained, experienced service  
technician.  
After completing installation, use these instructions  
to check out the product operation.  
Wallplate Installation  
The thermostat can be mounted horizontally on the wall or  
on a 2 in. x 4 in. wiring box. Position wallplate horizontally  
on the wall or on a 2 in. x 4 in. wiring box.  
4
1.  
Position and level the wallplate (for appearance  
only). The thermostat will function properly even  
when not level.  
®
U.S. Registered Trademark  
Copyright © 2004 Honeywell International Inc.  
All Rights Reserved  
69-0927-4  
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T8511G,R MICROELECTRONIC HEAT PUMP THERMOSTATS  
YES  
NO  
NO  
5
FEET  
[
1.5 METERS]  
NO  
M10106  
Fig. 1. Typical location of thermostat.  
WALL  
4.  
Position the wallplate over the holes, pulling wires  
through the wiring opening.  
WIRES  
THROUGH WALL  
5. Loosely insert the mounting screws into the holes.  
Tighten mounting screws.  
6.  
WIRING  
WALL  
All wiring must comply with local electrical codes and  
ordinances. Refer to Fig. 3 through 5 for typical hookups.  
A letter code is located near each terminal for  
identification.  
ANCHORS  
(2)  
CAUTION  
Disconnect power before wiring to prevent  
electrical shock or equipment damage.  
MOUNTING  
HOLES  
1.  
Loosen the terminal screws on the wallplate and  
connect the system wires. See Fig. 6.  
MOUNTING  
SCREWS  
IMPORTANT  
Use 18 gauge, color-coded thermostat cable for  
M6530  
proper wiring.  
Fig. 2. Mounting the wallplate.  
2.  
3.  
4.  
Securely tighten each terminal screw.  
Push excess wire back into the hole.  
Plug the hole with nonflammable insulation to  
prevent drafts from affecting the thermostat.  
2
.
.
Use a pencil to mark the mounting holes. See  
Fig. 2.  
3
Remove the wallplate from the wall and drill two  
3
/16 inch holes in the wall (if drywall) as marked. For  
firmer material such as plaster or wood, drill two  
/32 inch holes. Gently tap anchors (provided) into  
the drilled holes until flush with the wall.  
7
69-0927—4  
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T8511G,R MICROELECTRONIC HEAT PUMP THERMOSTATS  
THERMOSTAT  
THERMOSTAT  
OT  
OT  
B
O
G
Y
C
L
R
OT  
OT  
W1 O/B  
G
Y1  
C
E
W2  
L
R
2
2
OUTDOOR  
OUTDOOR  
TEMPERATURE  
SENSOR  
TEMPERATURE  
SENSOR  
EM. HEAT  
RELAY  
HEAT  
RELAY 2  
EQUIPMENT  
MONITOR  
COMPRESSOR  
CONTACTOR  
COMPRESSOR  
CONTACTOR  
EQUIPMENT  
MONITOR  
FAN  
FAN  
RELAY  
RELAY  
COOL  
CHANGEOVER  
VALVE  
COOL/HEAT  
CHANGEOVER  
VALVE  
HEAT  
CHANGEOVER  
VALVE  
HEAT  
RELAY 1  
1
1
L1  
L1  
(HOT)  
(
HOT)  
L2  
L2  
1
2
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND  
OVERLOAD PROTECTION AS REQUIRED.  
1
2
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND  
OVERLOAD PROTECTION AS REQUIRED.  
AVAILABLE ON SELECT MODELS.  
M4829  
AVAILABLE ON SELECT MODELS.  
M4830  
Fig. 3. Typical hookup in heat pump application.  
Fig. 5. Typical hookup in heat pump application with  
emergency heat relay and O/B terminal.  
THERMOSTAT  
OT  
OT  
W2  
O
G
Y
C
E
L
R
2
OUTDOOR  
TEMPERATURE  
SENSOR  
EM. HEAT  
RELAY  
EQUIPMENT  
MONITOR  
COMPRESSOR  
CONTACTOR  
FOR STRAIGHT  
INSERTION STRIP  
5/16 IN. (8 MM).  
FOR WRAPAROUND  
INSERTION STRIP  
FAN  
RELAY  
7/16 IN. (11 MM).  
M4826  
COOL  
CHANGEOVER  
VALVE  
Fig. 6. Proper wiring technique.  
1
Mounting Thermostat  
L1  
(
HOT)  
1. Engage tabs at the top of the thermostat and  
AUX. HEAT  
RELAY  
L2  
wallplate. See Fig. 7.  
1
2
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND  
OVERLOAD PROTECTION AS REQUIRED.  
2. Press lower edge of case to close and latch.  
AVAILABLE ON SELECT MODELS.  
M4828  
Fig. 4. Typical hookup in heat pump system  
with emergency heat relay.  
3
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T8511G,R MICROELECTRONIC HEAT PUMP THERMOSTATS  
A. ENGAGE TABS AT TOP OF THERMOSTAT AND WALLPLATE.  
Heat: The thermostat controls the heating.  
Off: Both the heating and cooling are off.  
Cool: The thermostat controls the cooling.  
Auto: The thermostat automatically changes between  
heating and cooling operation, depending on the  
indoor temperature.  
Fan settings control the system fan as follows:  
On: Fan operates continuously.  
Auto: Equipment controls fan.  
B. PRESS LOWER EDGE OF CASE TO LATCH.  
The system default setting is Heat and the fan default  
setting is Auto. Use the keyboard or system and fan  
switches, depending on model, to change to the desired  
settings. See Figs. 9 and 10.  
i
EM. HEAT HEAT OFF COOL  
EM. HEAT HEAT OFF COOL  
SYSTEM  
M6798A  
Selection for heating or cooling  
equipment operation.  
FAN  
ON AUTO  
On - Fan runs continuously  
Auto - Fan runs when  
heating or cooling  
equipment operates  
Heat  
Off  
Cool  
-
Heating equipment  
No equipment  
Cooling equipment  
-
-
ON AUTO  
Fig. 7. Mounting thermostat on wallplate.  
NOTE: To remove the thermostat from the wall, first  
pull out at the bottom of the thermostat; remove  
top last.  
M11037  
Using Thermostat Keys  
Fig. 9. T8511R (manual changeover) system  
and fan switches location.  
The thermostat keys are used to:  
•
•
•
•
•
set temperature,  
display present setting,  
configure Installer Setup,  
check System-Test,  
display outdoor temperature (select models).  
i
The T8511G has keys to:  
System  
•
•
set the system operation,  
set the fan operation.  
System  
Fan  
Ph er ea st isn gt oo sr e cl eo co tl ing  
equipment.  
Ph er ea st isn gt oo sr e cl eo co tl ing  
equipment.  
Em. Ht.-Emergency heating  
Heat— Heating equipment  
On— Fan runs continuously  
Auto—Fan runs when  
heating or cooling  
Off  
— No equipment  
System  
Fan  
Cool—Cooling equipment  
Auto—Thermostat  
equipment operates  
See Fig. 8 for the key information.  
ah ue taot mi n ga t ai c  
equipment.  
n
a
dl l yc os oe ll ie  
n
c
gts  
Fan  
INCREASE  
1
TEMPERATURE  
SETTING  
DECREASE  
TEMPERATURE  
SETTING  
i
1
CHECK LIGHT ON SELECT MODELS  
M10147  
DISPLAY PRESENT  
SETTINGS AND SCROLL  
THROUGH INSTALLER  
SETUP MODES  
Fig. 10. T8511G (automatic changeover) system  
and fan keys location.  
(INFORMATION KEY)  
M6801  
NOTE: Always press the system and fan keys with your  
fingertip or similar blunt tool. Sharp instruments  
like a pen or pencil point can damage the  
keyboard.  
Fig. 8. Thermostat key locations and descriptions.  
SETTINGS  
System and Fan Settings  
Temperature Settings  
System settings control the thermostat operation as  
follows:  
The default setpoint for heat is 70°F (21°C) and for cool is  
78°F (25.5°C). Press the increase ▲ or decrease ▲ key to  
change the present setting. To change between heat and  
Em. Heat: Emergency heat relay is automatically  
controlled by the thermostat. The cooling system is  
off. The compressor is de-energized.  
cool, press the Information  
changed appears.  
i key until the setting to be  
69-0927—4  
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T8511G,R MICROELECTRONIC HEAT PUMP THERMOSTATS  
INSTALLER SETUP  
Em Ht Temporary Setting  
Aux Ht  
Remote  
Room  
NOTE: For most applications, the thermostat factory-  
settings do not need to be changed. Review the  
factory settings in Table 2 and if no changes are  
necessary, go to the Installer System-Test  
section.  
%Humid  
Outdoor  
Heat Cool  
Repl  
Batt  
Wait  
System  
Fan  
Em HeatOffCool Auto Only OnAuto  
The Installer Setup is used to customize the thermostat to  
specific systems. Some of the options include temperature  
display, changeover, minimum equipment on time and  
minimum off time. Installer numbers are listed in Table 2.  
The table includes all the configuration options and the  
factory-settings available for the T8511.  
M4844  
Fig. 11. Display of all the segments of the LCD.  
INSTALLER SETUP  
NUMBER DISPLAY  
(COLUMN 2 OF TABLE 2)  
IMPORTANT  
The Installer Setup must be set correctly for the  
HVAC equipment, thermostat and subbase to  
operate properly.  
FACTORY SETTING OR  
OTHER CHOICE DISPLAY  
COLUMN 3 OR 5 OF TABLE 2)  
(
A combination of key presses are required to use the  
Installer Setup feature.  
—
To enter the Installer Setup, press and hold the  
Information key with the increase ▲ and decrease  
keys until the first number is displayed. All display  
i
▲
segments appear for approximately three seconds  
before the number is displayed. See Figs. 11 and 12.  
To advance to the next Installer Setup, press the  
—
—
—
Information  
To change a setting, use the increase ▲ or decrease  
key.  
To exit the Installer Setup, press and hold the  
Information key until the display returns to normal  
approximately three seconds). The display scrolls the  
i key.  
M10105A  
▲
Fig. 12. Display of Installer Setup and setting.  
i
NOTE: Only configurable numbers are shown.  
(
numbers backwards to get to the normal display. The  
Installer Setup is automatically exited if no key  
presses are made for five minutes.  
Table 2. Thermostat Installer Setup Options.  
Installer Setup  
Number  
Other Choices  
(Press ▲ or ▲ key to change)  
(
Press  
to change)  
01 thru 04  
Heating cycle 05  
i
key  
Factory-Setting  
Display Description  
Actual  
Setting  
Select  
Not used  
Display Description  
—
—
—
—
—
03  
—
Stage 2  
03, 06 03—3 cph used for stage 1  
rate  
06  
Not used  
or 09  
heat pump systems  
—
07  
09  
Emergency heat  
06—6 cph used for  
conventional systems  
0
9—9 cph used for electric  
heat systems  
Not used  
08 thru 11  
12  
T8511G only)  
—
—
—
—
—
—
Changeover  
(
01  
Manual changeover  
00,  00—Automatic changeover  
Not used  
13  
14  
—
—
—
—
Degree  
temperature  
display  
00  
Temperature is  
displayed in °F  
01  
Temperature is displayed in  
°C  
Not used  
15 thru 18  
—
—
—
—
—
a
The cycle rate for the last stage of heat is adjustable with 6 being the factory setting.  
(Continued)  
5
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T8511G,R MICROELECTRONIC HEAT PUMP THERMOSTATS  
Table 2. Thermostat Installer Setup Options (Continued).  
Installer Setup  
Number  
Other Choices  
(Press ▲ or ▲ key to change)  
(Press  
i
key  
Factory-Setting  
Description  
Actual  
Select  
to change)  
Display  
00  
Display  
Description  
Setting  
Extended fan 19  
operation in  
heating  
No extended fan  
operation after the call  
for heat ends  
01  
01  
—
Fan operation is extended  
90 seconds after the call for  
heat ends  
Extended fan 20  
operation in  
cooling  
00  
No extended fan  
operation after the call  
for cool ends  
Fan operation is extended  
90 seconds after the call for  
cool ends  
Not used  
21 thru 23  
24  
—
—
—
—
Outdoor  
temperature  
display  
00  
No outdoor temperature 01  
is displayed  
Outdoor temperature is  
displayed. Needs a  
C7089B1000 Outdoor  
Sensor to operate.  
Not used  
25 thru 28  
29  
—
—
—
—
—
—
O/B terminal  
energized in  
heating or  
cooling  
00  
O/B terminal is  
energized for reversing  
valve in cooling  
01  
O/B terminal is energized for  
reversing valve in heating  
Not used  
30 thru 32  
33  
—
—
—
—
Minimum off  
time for the  
compressor  
05  
5 minute minimum off  
time for the compressor 02, 03 (0 thru 5) the compressor will  
00, 01, Minimum number of minutes  
or 04  
be off between calls for the  
compressor  
34  
90  
Heating setpoint can be 40 thru Number can be set  
set no higher than 90°F 90 anywhere between 40 and  
0 in 1°F increments  
Heating  
setpoint range  
stop  
9
a
a
Cooling setpoint can be 45 thru Number can be set  
a
set no lower than 45°F 99 anywhere between 45 and  
99 in 1°F increments  
Cooling  
setpoint range  
stop  
35  
36  
37  
45  
00  
00  
a
System On  
display  
LCD On symbol is  
displayed when system  
is energized  
01  
Display is disabled, usually  
set for 01 for a zoned system  
Temperature  
display  
adjustment  
No difference in  
-3 thru 01—Display adjusts to 1°F  
displayed temperature 03  
higher than actual room  
and actual room  
temperature  
temperature  
02—Display adjusts to 2°F  
higher than actual room  
temperature  
0
3—Display adjusts to 3°F  
higher than actual room  
temperature  
-
-
-
1—Display adjusts to 1°F  
lower than actual room  
temperature  
2—Display adjusts to 2°F  
lower than actual room  
temperature  
3—Display adjusts to 3°F  
lower than actual room  
temperature  
a
T8511G is 48°F.  
69-0927—4  
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T8511G,R MICROELECTRONIC HEAT PUMP THERMOSTATS  
NOTE: Press and hold the increase ▲ and decrease ▲  
keys for three seconds to exit the system-test.  
The system-test times out after five minutes  
INSTALLER SYSTEM-TEST  
Use the Installer System-Test to check the thermostat  
configurations and operation. Refer to Table 3 for a list of  
the available system-tests.  
without any key presses.  
Table 3. Tests Available in the Installer System-Test.  
Test  
To start the system-test:  
Number  
System-Test Description  
NOTE: The minimum off time for compressors is  
bypassed during the Installer System-Test.  
1
0-19  
0-29  
Heating equipment can be turned on and off  
2
Emergency heat (select models) equipment  
can be turned on and off  
Press and hold the increase ▲ and decrease ▲ keys, at  
the same time, until two zeros appear. All segments of the  
LCD are displayed before the two zeros appear.  
30-39  
40-49  
60-69  
Cooling equipment can be turned on and off  
Fan equipment can be turned on and off  
System key or system switch position test  
Em Ht Temporary Setting  
Aux Ht  
Remote  
Room  
70-79  
Thermostat information including date code  
and software versions are displayed  
%Humid  
Outdoor  
Heat Cool  
Refer to Table 4 for the directions and results of the  
specific tests.  
Repl  
Batt  
Wait  
System  
Fan  
Em HeatOffCool Auto Only OnAuto  
M4844  
M6792  
TEST NUMBER  
Table 4. Installer System-Test Options.  
Description  
Key To  
Press  
Test  
Number  
Heating Equipment System-Test  
i
10  
Enter heating equipment system-test. (Set T8511R system switch to HEAT and fan switch to  
AUTO.)  
▲
▲
▲
▲
11  
12  
11  
10  
Stage-one heat comes on. The system fan is also energized.  
Stage-two heat comes on. Stage-one heat and system fan remain on.  
Stage-two heat turns off.  
Stage-one heat and system fan turn off.  
Emergency Heating Equipment System-Testa  
i
20  
Change from heating to emergency heating equipment system-test.  
Set T8511R system switch to EM. HT.)  
(
▲ b  
▲ b  
21  
20  
Emergency heat comes on. System fan also comes on.  
Emergency heat turns off. (Set T8511R system switch to OFF.)  
Cooling Equipment System-Test  
i
30  
Change from heating or emergency heating to cooling equipment system-test.  
Set T8511R system switch to COOL.)  
(
▲
▲
31  
30  
Stage-one cooling and system fan come on.  
Stage-one cool and system fan turn off.  
a
b
Available on select models.  
T8511R models with fixed emergency heat output will not respond to this key press.  
(Continued)  
7
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T8511G,R MICROELECTRONIC HEAT PUMP THERMOSTATS  
Table 4. Installer System-Test Options. (Continued)  
Description  
Key To  
Press  
Test  
Number  
Fan Equipment System-Test (T8511G only)  
i
40  
41  
40  
Change from cooling to fan equipment system-test.  
▲
Fan comes on.  
Fan turns off.  
▲
T8511G System Key or T8511R System Switch Operation System-Test  
IMPORTANT  
Test numbers will only be displayed when the system is configured for the selected function.  
EXAMPLE: Numbers 60, 61 and 62 are the only numbers that will be displayed when a system is configured for  
heat only.  
SYSTEM KEY OR SWITCH SYSTEM-TEST (When system switch is used, move switch to see Test Number.)  
i
60  
61  
62  
63  
64  
65  
Change from fan to key operation system-test.  
System  
System  
System  
System  
System  
Heat Test number is displayed. (Set T8511R system switch to HEAT.)  
Off Test number is displayed. (Set T8511R system switch to OFF.)  
Cool Test number is displayed. (Set T8511R system switch to COOL.)  
Auto Test number is displayed.  
Emergency heat Test number is displayed. (Set T8511R system switch to EM.HT.)  
NOTE: Press system key again to repeat the System Key System-Test.  
FAN KEY SYSTEM-TEST (T8511G only)  
Fan  
Fan  
68  
69  
Fan on Test number is displayed.  
Fan off Test number is displayed.  
Thermostat Information  
1.  
Press the Information  
stat information.  
i
key to access the thermo-  
3. Press the increase ▲ key again to display the  
software identification code.  
(Example: 02 = software ID code 2)  
M4864  
M4866  
2.  
Press the increase ▲ key to display the production  
date code. The first two large digits are the month  
and the third digit is the last digit of the year.  
4. Press the increase ▲ key again to display the  
software revision number.  
(Example: 026 = February 1996)  
(Example: 001 = revision number 1)  
M4865  
M6791  
69-0927—4  
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T8511G,R MICROELECTRONIC HEAT PUMP THERMOSTATS  
5.  
Press the increase ▲ key again to display the  
EEPROM identification code.  
Example: 222 = EEPROM ID 222)  
CHECKOUT  
(
Outdoor Temperature Sensor  
(Where Applicable)  
Allow the outdoor temperature sensor to soak in the  
outdoor air for a minimum of five minutes before taking a  
reading. With an accurate thermometer (±1°F [±0.5°C]),  
measure the temperature at the sensor location, allowing  
time for the thermometer to stabilize before reading. Match  
the thermometer reading to the outdoor temperature  
display at the thermostat.  
M4867  
6.  
Press and hold the increase ▲ and decrease ▲  
keys together, until the room temperature is  
displayed, to exit the system-test. The system-test  
times out after five minutes without any key presses.  
TROUBLESHOOTING GUIDE  
Symptom  
Possible Cause  
Action  
Display will not  
come on.  
Thermostat is not being  
powered.  
•
•
Check that C terminal is connected to the system  
transformer.  
Check for 24 Vac between C and R or RH terminals.  
—
If missing 24 Vac:  
check if the circuit breaker is tripped—reset the  
circuit breaker.  
—
—
—
check if the system fuse is blown—replace the fuse.  
check if the power switch on the HVAC equipment is  
in the Off position—set to the On position.  
check wiring between thermostat and HVAC  
equipment—replace any broken wires and tighten  
any loose connections.  
—
—
If 24 Vac is present, proceed with troubleshooting.  
Thermostat microprocessor is Remove the thermostat from the wallplate for 2 minutes. After  
locked up. 2 minutes, replace the thermostat on the wallplate.  
Temperature  
display is incorrect. been reconfigured.  
Room temperature display has Enter Installer Setup mode number 37 and reconfigure the  
display.  
Thermostat is configured for °F Enter Installer Setup mode number 14 and reconfigure the  
or °C display a  
Bad thermostat location.  
.
display.  
Relocate the thermostat.  
Temperature  
The upper or lower temperature Check the temperature setpoints:  
limits were reached.  
settings will not  
change. (Example:  
Cannot set the  
•
•
Heating limits are 40 to 90°F (4.5 to 32°C)  
T8511R cooling limits are 45 to 99°F (7 to 35°C) and  
T8511G cooling limits are 48 to 99°F  
heating higher or  
the cooling lower.)  
The setpoint temperature range Check Installer Setup mode numbers 34 and 35 and  
stops were configured.  
reconfigure the setpoint stops.  
Heating will not  
come on.  
No power to the thermostat.  
•
Check that C terminal is connected to the system  
transformer.  
Check for 24 Vac between C and R or RH terminals.  
•
—
If missing 24 Vac:  
check if the circuit breaker is tripped—reset the  
circuit breaker.  
—
—
—
check if the system fuse is blown—replace the fuse.  
check if the system switch at the equipment is in the  
Off position—set to On position.  
—
check wiring between thermostat and HVAC  
equipment—replace any broken wires and tighten  
any loose connections.  
—
If 24 Vac is present, proceed with troubleshooting.  
a
Available on select models.  
(Continued)  
9
69-0927—4  
href="
T8511G,R MICROELECTRONIC HEAT PUMP THERMOSTATS  
TROUBLESHOOTING GUIDE (Continued)  
Symptom  
Possible Cause  
Action  
Heating will not  
come on.  
Thermostat minimum off time is Wait up to five minutes for the system to respond.  
activated.  
(Continued)  
System selection is not set to  
Heat.  
Set system selection to Heat.  
O/B terminal configured  
incorrectly .  
Check Installer Setup mode number 29 and reconfigure  
correctly.  
a
O or B terminal miswireda.  
Check system description to determine whether changeover  
should be energized in heat (B) or cool (O). Rewire if  
necessary.  
Cooling will not  
come on.  
No power to the thermostat.  
•
Check that C terminal is connected to the system  
transformer.  
Check for 24 Vac between C and R or RC and Y terminals.  
•
—
If missing 24 Vac:  
check if the circuit breaker is tripped—reset the  
circuit breaker.  
—
—
—
check if the system fuse is blown—replace the fuse.  
check if the system switch at the equipment is in the  
Off position—set to the On position.  
—
check wiring between thermostat and HVAC  
equipment—replace any broken wires and tighten  
any loose connections.  
—
If 24 Vac is present, proceed with troubleshooting.  
Thermostat minimum off time is  
activated.  
•
•
Wait up to five minutes for the system to respond.  
Enter Installer Setup mode number 33. Reconfigure  
minimum off time (if required).  
System selection is not set to  
Cool.  
Set system selection to Cool.  
O/B terminal configured  
incorrectly .  
Check Installer Setup mode number 29 and reconfigure  
correctly.  
a
O or B terminal miswireda.  
Check system description to determine whether changeover  
should be energized in heat (B) or cool (O). Rewire if  
necessary.  
System On  
Heating equipment is not  
operating.  
Verify operation of heating equipment in self-test.  
indicator is lit, but  
no heat is being  
delivered.  
a
Available on select models.  
69-0927—4  
10  
href="
1
1
69-0927—4  
href="
Automation and Control Solutions  
Honeywell International Inc.  
985 Douglas Drive North  
Golden Valley, MN 55422  
Honeywell Limited-Honeywell Limitée  
35 Dynamic Drive  
Scarorough, Ontario  
M1V 4Z9  
1
69-0927—4 G.H. Rev. 04-04  
www.honeywell.com/yourhome  

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