Honeywell TL8100 User Manual

69-2018EFS-01

7 DAY PROGRAMMABLE HYDRONIC THERMOSTAT

This thermostat can be used to control the following heating 

systems:

• gas, oil or electric systems

• hot water heating

• hot air system with no fan control

• millivolt system (e.g., gas fireplace)

• electric heating up to 1200 W @ 240 V max.

The thermostat normally 

displays the measured 

ambient temperature. To view 

the setpoint temperature, 

briefly press either of the 

 

buttons. The setpoint 

temperature will appear for 5 

seconds.

To adjust the setpoint, press one of the 

 buttons until the 

desired temperature is displayed.

The thermostat has 3 preset temperatures:

To use a preset temperature:

Press the corresponding button (

,   or 

). The 

temperature and the corresponding icon will be displayed.

To change a preset temperature:

1. Set the desired temperature using the 

 buttons.

2. Press and hold the corresponding button (

,   or 

) 

until the icon is displayed on the screen (approximately 

3 seconds).

Programming 
buttons

Temperature 
preset buttons

Temperature 
adjustment 
buttons

Time and day

Temperature

Mode and preset 
temperature 
indicators

Heating 
indicator

Low-battery 
indicator

Appears during the
setpoint display

Comfort temperature 

68°F (20°C)

Economy temperature 

64°F (18°C)

Vacation temperature 

50°F (10°C)