25
TM21H02 Thermostat
T
HERMOSTAT
F
EATURES
Number of Heating Stages: 2
Number of Cooling Stages: 1
Changeover: Manual
All controls on front
Batteries: Not required. Temperature settings are held
permanently in memory
S
ETTING
FAN
AND
SYSTEM S
WITCHES
Fan and system settings are controlled by using FAN and
SYSTEM switches located on the bottom of the thermostat case.
S
ETTING
THE
FAN S
WITCH
Auto: Normal setting for most homes. In cooling, the fan goes off and
on with the cooling equipment. In heating, the fan may start a few minutes after the heating equipment comes on.
On: The fan runs continuously. Use for improved air circulation and air quality.
S
ETTING
THE
SYSTEM S
WITCH
Cool: Normal setting for months when your home needs cooling (air conditioning). Digital display shows a snowflake
when cooling is on.
Off: Both heating and cooling are off.
Heat: Normal setting for months when your home needs heating. Digital display shows a flame when heating is on.
Em. Ht.: Switch to this setting when your home needs heat, but your equipment has failed or is not working properly.
E
M
H
T
AND
A
UX
H
T
I
NDICATIONS
The ▲ indicator points to either Em Ht or Aux Ht when these modes are active.
Em Ht: The▲ indicator points to Em Ht when the SYSTEM switch is set at Em Ht.
Aux Ht: The ▲ indicator points to Aux Ht when the living space needs auxiliary backup heat to help handle the heat-
ing load.
D
ISPLAYING
T
EMPERATURE
S
ETTING
NOTE:
Your temperature setting can be set anywhere from 40° to 99°F (5° to 37°C).
The temperature setting and the room temperature are shown separately on the digital display. The ▼ indicator
points to Set when the temperature setting is displayed and to Room when the room temperature is displayed.
1. To display the temperature setting on the digital display, press either the ▲ or ▼ key once.
C
HANGING
T
EMPERATURE
S
ETTING
To lower the temperature setting, press the ▼ key. When in the heating mode, lowering the temperature at night
or during the day can lower your energy costs.
To raise the temperature setting, press the ▲ key. When in the cooling mode, raising the temperature before
you leave for work or school also lowers your energy costs.
For more information, refer to the Owner’s Guide packaged with the thermostat.
1.
2.
THERMOSTAT OPERATION