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T8424D ELECTRONIC MULTISTAGE THERMOSTAT
69-1386-1
4
Fig. 7. Digital display and system
switches (FAN and SYSTEM).
Set Temperature Setpoint
NOTE: Temperature setpoint range is 40° to 99°F (5° to
37°C).
The temperature setpoint and the room temperature are
shown separately on the digital display. The
▼
indicator
points to
Set
when the temperature setpoint is displayed
and to
Room
when the room temperature is displayed
.
To set temperature setpoint:
1.
Select Heat or Cool by sliding the SYSTEM switch
in the lower right corner of the thermostat to the
desired mode. See Fig. 7.
2.
To display the temperature setpoint on the digital
display, press either the
▲
or
▼
key once. The
temperature setpoint is displayed for approxi-
mately five seconds as the indicator points to
Set
and flashes.
3.
To increase the temperature setpoint press the
▲
key. Each press changes the setpoint one degree;
press and hold to change the setpoint several
degrees.
4.
To decrease the temperature setpoint press the
▼
key. Each press changes the setpoint one degree;
press and hold to change the setpoint several
degrees.
Setting °F/°C Indication and Heat Cycle Rate
NOTE: To save changes to the °F/°C indication and the
heat cycle rate, all seven steps must be com-
pleted.
To set the °F/°C indication and heat cycle rate:
1.
If the temperature is displayed in °F, set the tem-
perature setpoint to 52°F. If the room temperature
is displayed in °C, set the temperature setpoint to
11°C.
2.
Press the
▲▼
keys simultaneously for more than
one second to light all segments on display and to
enter installer setup mode. When the keys are
released, a two-digit software revision code is dis-
played.
OPTIONAL SYSTEM CHECKOUT
When in steps 2 and 3 only, the
▼
key can be used to
turn heat or cool outputs on and off. Change the
SYSTEM switch setting to test heat or cool outputs. No
action takes place If the system switch is in the Off
position.
Examples: System setting at HEAT: If heat is on, the
▼
key turns it off; if heat is off,
▼
turns it on.
System setting at COOL: If cool is on,
▼
key
turns it off; if cool is off,
▼
turns it on.
NOTE: In Optional System Checkout for multistage
models, pressing the
▼
key turns on the first
stage output. (The second press of the
▼
key
turns on the second stage output.)
NOTE: In installer setup mode only, each press of the
▲
key momentarily displays 01. Each press of
the
▼
key momentarily displays 02. When the
keys are released, these two-digit codes are no
longer displayed.
SYSTEM
Cool O
ff H
eat
Auto On
FAN
M14678
TEMPERATURE DISPLAY
INCREASE SETTING
DECREASE SETTING
FAN SWITCH
SYSTEM SWITCH
Set
Room
INDICATOR
ROOM TEMPERATURE
SETPOINT TEMPERATURE
M14679
M14680
M14681
M14682
M14683
M14686
M14684
M14685