Honeywell chronotherm iii t8611m User Manual

69-1415—1

4

1. Engage tabs at the top of the thermostat and 

wallplate. See Fig. 6.

2. Press lower edge of case to close and latch.

NOTE: To remove the thermostat from the wall, first pull 

out at the bottom of the thermostat; remove top 
last.

The thermostat keys are used to:
• set current day and time,
• program times and setpoints for heating and cooling,
• temporarily override program temperatures, 
• display present setting, 
• configure Installer Setup, 
• check System Test,
• display outdoor temperature (select models),
• set the system operation, 
• set the fan operation. 

See Fig. 7 for the key location.

NOTE: Always press the keys with your fingertip or 

similar blunt tool. Sharp instruments like a pen 
or pencil point can damage the keyboard.

The system default setting is Heat and the fan default 
setting is Auto. Use the System and Fan keys to change 
the settings. See Fig. 8. The fan settings can be set for 
each program period individually. The system selection is 
for all the program periods.

System settings control the thermostat operation:

Em Heat: Defrost reset output relay (L) is on 

continuously. The thermostat cycles the 
Emergency Heat relay and the highest heat stage. 
Cooling system is off. Compressor is de-energized.

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:

On: Fan operates continuously.
Auto: Fan operates with equipment.

M14634

PRESS LOWER 

EDGE OF CASE 

TO LATCH.

ENGAGE TABS 

AT TOP OF 

THERMOSTAT 

AND WALLPLATE.

M14624

Time

Set Program

System

Fan

Run

Program

Hold Temp

Set Current

Day/Time

Wake

Leave

Return

Sleep

Day

Heat/Cool

Settings

Daylight

Time

Copy

INCREASE TEMPERATURE 
SETTING OR SCROLL 
FORWARD THROUGH 
INSTALLER SETUP OPTIONS

DECREASE TEMPERATURE 
SETTING OR SCROLL 
BACKWARD THROUGH 
INSTALLER SETUP OPTIONS

DISPLAY INFORMATION
SUCH AS PRESENT 
SETTINGS AND OUTDOOR 
TEMPERATURE

RETURN TO 
NORMAL
OPERATIONS

ENTER 
INDEFINITE 
OR TIMED 
HOLD MODE

SET CURRENT 
DAY AND TIME

SET CURRENT OR
PROGRAM DAY

CHANGE BETWEEN 
DAYLIGHT SAVINGS 
AND STANDARD TIME

INCREASE TIME SETTING
OR SCROLL FORWARD 
THROUGH INSTALLER SETUP 
AND SYSTEM TEST

DECREASE TIME SETTING OR 
SCROLL BACKWARD THROUGH 
INSTALLER SETUP AND SYSTEM TEST

COPY ONE PROGRAMMED 
DAY TO ANOTHER DAY

SET WAKE TIMES 
AND SETPOINTS

CHANGE BETWEEN 
HEATING AND COOLING 
SETPOINTS 

SET LEAVE TIMES 
AND SETPOINTS

SET RETURN TIMES 
AND SETPOINTS

SET SLEEP TIMES 
AND SETPOINTS

SELECT SYSTEM 
OPERATION 

SELECT FAN 
OPERATION