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Most Recent Honeywell T8400C Questions
How Do I Wire This Into My Rv?
(Posted by allennorrid 1 year ago)
Blank Screen On T8400c Thermostat
what causes a blank screen on the thermostat?
what causes a blank screen on the thermostat?
(Posted by Biliboy52 2 years ago)
I Can't Get The To Read
I took the faith off to clean it now and won't read the digital temperature
I took the faith off to clean it now and won't read the digital temperature
(Posted by greenpenny15 3 years ago)
Our Thermostat Screen T8400c 1024/u Went Blank .we Understand That Thi Thermos
We understand that this thermostat Is opsolet ,what we should replace With? .
We understand that this thermostat Is opsolet ,what we should replace With? .
(Posted by tedmusnicki 5 years ago)
Popular 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
... permanently in memory.
69-1490
2 Congratulations on the purchase of this thermostat in an effort to provide you to use. The ▲ and ▼ keys make it easy for batteries. Batteries are not required because your temperature setting.
• Large digital display. Over 100 years of Honeywell engineering expertise went into the making of your new...
Owner's Manual - Page 3
... Auto On
FAN SWITCH
M10273
3
69-1490
In cooling, the
fan goes off and on . Settings
Setting FAN and SYSTEM Switches
Fan and system settings are controlled by using FAN and SYSTEM switches located on the bottom of the thermostat case. First set the FAN switch:
Auto: Normal setting for improved air
circulation and air quality.
Owner's Manual - Page 4
... heating and cooling are off. Ht.: (Not available on .
Digital display shows a flame
when heating is on all models.) Switch to this
setting when your home needs heat, but your
equipment has failed or is on. SYSTEM SWITCH
M10274
69-1490
4 Digital display
shows a snowflake when cooling is not working properly.
Em. SYSTEM Cool...
Owner's Manual - Page 5
INDICATOR
Em Ht
Set
Room
M18425
5
69-1490 Em Ht and Aux Ht Indications
Emergency Heat (Em Ht) and Auxiliary Heat (Aux Ht) indications are ... Ht when the living space needs auxiliary backup heat to either Em Ht or Aux Ht when these modes are not available on all models. The ▲ indicator points to help handle the heating load. Em Ht: Aux Ht:
The ▲ indicator points to Em ...
Owner's Manual - Page 6
...9650; or ▼ key once. 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 and to 37°C). The ▼ indicator points to Set when the temperature setting is displayed.
1.
To display the temperature setting on the digital display. Set
Room
INDICATOR
M18441
69-1490...
Owner's Manual - Page 7
... your energy costs. When in the cooling mode, raising the temperature before you leave for work or school also lowers your energy costs.
Changing Temperature Setting
1. To raise the temperature setting, press the ▲ key. Set
Room
M18443
7
69-1490 Set
Room
M18442
2. To lower the temperature...
Owner's Manual - Page 8
..., where you live, the number of energy saving periods you choose and your thermostat to automatically change the temperature setting, you might want to consider purchasing the Honeywell Chronotherm® Programmable Thermostat. With this thermostat in the cooling mode by lowering the temperature setting 5°F (3°C) to 10°F (5°C) at night and during the day...
Owner's Manual - Page 10
... breaker and replace or reset if necessary.
• Check for air movement at the register.
• Check power to the heating or cooling equipment.
• Adjust the temperature by pressing either the ▲ or ▼ key.
69-1490
10 See equipment manufacturer instructions.
Temperature setting is below 50°F (10°C). Troubleshooting Guide
CAUTION
To...
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.
Installation Instructions - Page 1
....
2.
Check the ratings given in a sealed tube. Do not install the thermostat where it carefully.
® U.S. drafts or dead spots behind the thermostat.
The T8400C SUPER TRADELINE® model also includes two decorator cover plates for wiring and mounting thermostat) and owner's guide. After installation is replacing a control that contains mercury in a sealed tube, do not place...
Installation Instructions - Page 2
...
Mount decorator cover plate (SUPER TRADELINE® model only), wallplate, T8400C or T8401C, and the screws provided (see Wiring section. Pull the thermostat wire through the entrance hole on the wall.
2. The shape of the terminals permits insertion of straight or wraparound wiring connections; The T8400C Thermostat is acceptable. x 5-3/4 IN.
x 3-7/8 IN.
Mounting decorator...
Installation Instructions - Page 3
...wiring to Wallplate
1.
Swing down the thermostat and press the lower edge of the thermostat and wallplate.
2.
Wiring connections. PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED.
2 IN T8401C INSTALLATIONS, CONNECT C TERMINAL. M18416
B PRESS LOWER EDGE OF
CASE TO LATCH.
FAN Switch
Fan switch settings are controlled manually by the heating equipment and may start...
Installation Instructions - Page 4
...
OPTIONAL SYSTEM CHECKOUT When in the bottom right corner of the thermostat to 37°C).
M14684
System setting at HEAT: If heat is displayed and to change the setpoint several degrees.
NOTE:
M14686
In installer setup mode only, each press of the t key momentarily displays 02. press and hold to the °F/°C indication and the...
Installation Instructions - Page 5
..., exit installer setup mode and return to display the heat cycle rate of an outdoor temperature may start a few minutes after the heating equipment turns on (on select models.
7. When using an electric heat thermostat, the fan starts immediately.
3. bRefer to raise the temperature setting above the room temperature. Press the s key to equipment manufacturer's instructions. Heating...
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