Honeywell T8400C Support Question
Honeywell T8400C Support Question
Find answers below for this question about Honeywell T8400C.Need a Honeywell T8400C manual? We have 2 online manuals for this item!
Question posted by rondaklubben on January 12th, 2012
Our Honeywell T8400c Thermostate Went Blank.
our? thermostate is blank if set on heat. shows numbers if set on cool. why isn't it workin
Current Answers
Related Honeywell T8400C Manual Pages
Owner's Manual - Page 1
Set
Room
FAN Auto On
SYSTEM Cool Off Heat
M18535
Em Ht Aux Ht
Set
Room
Electronic Thermostat
OWNER'S GUIDE
FAN Auto On
SYSTEM Cool Off Heat Em.Ht. M18539
1
69-1490
69-1490
Owner's Manual - Page 2
... living environment.
• Simple and easy to change your new thermostat! Batteries are not required because your temperature settings are held permanently in an effort to provide you to use. Over 100 years of Honeywell engineering expertise went into the making of your temperature setting.
• Large digital display. The ▲ and ▼ keys make...
Owner's Manual - Page 3
... improved air
circulation and air quality.
Use for most homes. In heating, the fan may start a few minutes after
the heating equipment comes on the bottom of the thermostat case. On:
The fan runs continuously.
Settings
Setting FAN and SYSTEM Switches
Fan and system settings are controlled by using FAN and SYSTEM switches located on . In...
Owner's Manual - Page 4
... SWITCH
M10274
69-1490
4 Off:
Both heating and cooling are off. Em. Heat: Normal setting for months when your home
needs cooling (air conditioning).
Digital display shows a flame
when heating is on .
Then set the SYSTEM switch:
Cool: Normal setting for months when your home
needs heating. Digital display
shows a snowflake when cooling is not working properly.
Ht.: (Not...
Owner's Manual - Page 5
The ▲ indicator points to Aux Ht when the living space needs auxiliary backup heat to Em Ht when the SYSTEM switch is set at Em Ht. INDICATOR
Em Ht
Set
Room
M18425
5
69-1490 The ▲ indicator points to either Em Ht or Aux Ht when these modes are not available on all...
Owner's Manual - Page 6
... separately on the digital display, press either the ▲ or ▼ key once. The ▼ indicator points to Set when the temperature setting is displayed and to 37°C). Displaying Temperature Setting
NOTE: Your temperature setting can be set anywhere from 40° to 99°F (5° to Room when the room temperature is displayed.
1.
Owner's Manual - Page 7
Changing Temperature Setting
1.
When in the heating mode, lowering the temperature at night or during the day can lower your energy costs. Set
Room
M18443
7
69-1490 To lower the temperature setting, press the ▼ key. To raise the temperature setting, press the ▲ key. When in the cooling mode, raising the temperature before you leave for...
Owner's Manual - Page 8
..., the number of energy saving periods you choose and your thermostat to automatically change the temperature setting, you might want to 10°F (5°C) at night and during the day before you leave for work or school. With this thermostat in the cooling mode by lowering the temperature setting 5°F (3°C) to consider purchasing the Honeywell Chronotherm...
Owner's Manual - Page 9
...176;C) DECREASE*
12 TO 18 TO 23 TO 25 TO UP TO
16% 22% 25% 29% 30%
HEAT
PERCENT OF COOLING COSTS YOU CAN SAVE
SAVINGS FOR ONCE-A-DAY 10°F (5°C) INCREASE*
7 TO 9% 10 TO 11% ...;C) INCREASE*
11 TO 15% 16 TO 18% 19 TO 22% 23 TO 33%
COOL
* YOUR SAVINGS DEPENDS ON HOME SIZE AND ACTUAL HEAT LOSS OR GAIN, GEOGRAPHIC LOCATION, FREQUENCY OF TEMPERATURES CHANGE, AND RANGE IN DEGREES OF CHANGE...
Owner's Manual - Page 10
....
• Check power to the heating or cooling equipment.
• Adjust the temperature by pressing either the ▲ or ▼ key.
69-1490
10 Temperature setting is too warm or cool.
• Check that the SYSTEM switch on .
See equipment manufacturer instructions. Heating or cooling does not come on the thermostat is below 50°F (10°...
Owner's Manual - Page 11
For service, contact your local heating and cooling contractor:
11
69-1490
If you have questions concerning this thermostat, call Honeywell Customer Assistance at 1-800-468-1502, Monday-Friday, 7:00 am-5:30 pm, Central time.
Owner's Manual - Page 12
Registered Trademark
69-1490 J.H. 9-00
6ww9w-1.h4o9ne0ywell.com/yourhome
12 Honeywell Limited-Honeywell Limitée
1985 Douglas Drive North 35 Dynamic Drive
Golden Valley, MN 55422
Scarborough, Ontario M1V 4Z9
Copyright © 2000 Honeywell
All Rights Reserved
® U.S. Automation and Control Solutions
Honeywell International Inc.
Installation Instructions - Page 1
... in a sealed tube, do not place your old control in the trash. T8400C and T8401C Electronic Thermostats
INSTALLATION INSTRUCTIONS
The T8400C and T8401C Thermostats provide singlestage, non-programmable temperature control for 24V heating-cooling systems with good air circulation at average temperature.
The T8400C SUPER TRADELINE® model also includes two decorator cover plates for wiring...
Installation Instructions - Page 2
... entrance hole on the decorator cover plate, then through the heating/ cooling system controls and is adaptable to most 4-wire, 18 to 30 Vac heating-cooling systems.
The T8401C Thermostat is powered directly from affecting the thermostat;
Mount decorator cover plate (SUPER TRADELINE® model only), wallplate, T8400C or T8401C, and the screws provided (see Wiring section...
Installation Instructions - Page 3
T8400C/T8401C heat-cool wiring diagram in single transformer system with the heating equipment.
3
69-1480-1 Swing down the thermostat and press the lower edge of the thermostat and wallplate.
2. M11021B
Fig. 5. Set
Room
Set
Room
FAN Auto On
SYSTEM Cool Off Heat
FAN Auto
SYSTEM Cool Off Heat
A ENGAGE TABS AT TOP
OF THERMOSTAT WITH SLOTS ON WALLPLATE. OPERATION
Setting FAN and ...
Installation Instructions - Page 4
... .
Each press of the s key momentarily displays 01.
TEMPERATURE DISPLAY
Set
Room
INCREASE SETTING
DECREASE SETTING
FAN Auto On
SYSTEM Cool Off Heat
3. M14685
2. Heat: The thermostat controls the heating system. M14681
4. The temperature setpoint is in the bottom left corner of the thermostat to turn heat or cool outputs on , the t key turns it off , t turns it on...
Installation Instructions - Page 5
... minutes after the heating equipment turns on (on select models.
7.
M14690
Table 1. Slide the SYSTEM switch to Cool and the FAN switch to lower the temperature setting several degrees above the room temperature. Press the t key to Auto.
2. Factory information is displayed. T8400C AND T8401C ELECTRONIC THERMOSTATS
10. Do not operate cooling if outdoor temperature is...
Installation Instructions - Page 6
Automation and Control Solutions
Honeywell
Honeywell Limited-Honeywell Limitée
1985 Douglas Drive North
35 Dynamic Drive
Golden Valley, MN 55422
Scarborough, Ontario
M1V 4Z9
69-1480-1 G.H. Rev. 2-02
www.honeywell.com/yourhome
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