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L3722C 7−DAY PROGRAMMABLE THERMOSTAT
Removing and Installing Thermostat
The thermostat hinges on tabs on the top of the subbase;
no tool is needed to remove the thermostat from the sub-
base. Pivot the bottom of the thermostat outward (releas-
ing the snaps), then lift up to remove.
To install it, first position the top tilted toward the wall brack-
et and align it until you feel the tabs and slots engage; then,
while the top is in place, pivot the bottom toward the wall
until the thermostat snaps into place.
Thermostat Output Table
Table 2 depicts the L3722C thermostat output states for
various input conditions. The following notes described
terms used in the table.
Table 2. Thermostat Outputs
Condition
W1
W2
Y1
Y2
G
Gas Heat, Auto Fan
Heat Demand, SMALL
X
Heat Demand, LARGE
X
X
Cool Demand, SMALL
X
X
Cool Demand, LARGE
X
X
X
No Demand
Gas Heat, Continuous Fan
Heat Demand, SMALL
X
X
Heat Demand, LARGE
X
X
X
Cool Demand, SMALL
X
X
Cool Demand, LARGE
X
X
X
No Demand
X
Electric Heat, Auto Fan
Heat Demand, SMALL
X
X
Heat Demand, LARGE
X
X
X
Cool Demand, SMALL
X
X
Cool Demand, LARGE
X
X
X
No Demand
Electric Heat, Continuous Fan
Heat Demand, SMALL
X
X
Heat Demand, LARGE
X
X
X
Cool Demand, SMALL
X
X
Cool Demand, LARGE
X
X
X
No Demand
X
NOTE − X = output is activated with 24VAC.
NOTE − The temperature ranges expressed in the following def-
initions of SMALL/LARGE" demands are for guidance only; ac-
tual temperatures may vary.
With a SMALL heat demand, temperature is:
below
setpoint –0.5F
but above
setpoint –1.5F
AND 30-minute upstage timer HAS NOT expired.
With a LARGE heat demand, temperature is:
less than
setpoint –1.5F
OR 30-minute upstage timer HAS expired.
With a SMALL cool demand, temperature is:
above
se0.5F
but below
se1.5F
AND 30-minute upstage timer HAS NOT expired.
With a LARGE cool demand, temperature is:
above
se1.5F
OR 30-minute upstage timer HAS expired.
Default Thermostat Settings
Default thermostat settings are in table 3 and the default
program is shown in table 4.
Table 3. Default Thermostat Settings
Mode
Heat (Perm. Hold)
Heat Setpoint (Perm Hold)
70°F (or 21°C)
Cool Setpoint (Perm Hold)
78°F (or 26°C)
Fan
Auto
Filter Reminder
OFF
Maintenance Reminder
OFF
Equipment Protection Timers
Reset Back to Zero
Autochangeover
OFF
Table 4. Default Program Settings (Time/Temp)
Programs
Time
Temp.− Heat
Temp.− Cool
All days − A
6:00am
70
_
F / 21
°
C
78
_
F / 26
°
C
All days − B
8:00am
62
_
F / 17
°
C
85
_
F / 29
°
C
All days − C
6:00pm
70
_
F / 21
°
C
78
_
F / 26
°
C
All days − D
10:00pm
62
_
F / 17
°
C
82
_
F / 28
°
C
Technical Specifications
Thermostat Type
Electronic programmable thermo-
stat for 2−Stage (gas or electric) Heat/2-Stage Cool, non−
heat pump, non−power robbing applications.
Table 5. L3722C Terminal Designations
Terminal
Description
R
24VAC
Y1
First-stage cooling
W1
First-stage heating
Y2
Second-stage cooling
W2
Second-stage heating
G
Fan control
L
Service Indicator
C
24VAC common
T
Outdoor temperature sensor connection 1
T
Outdoor temperature sensor connection 2
Power Supply Range
18VAC − 30VAC (24VAC nomi-
nal), 60Hz
CAUTION
24VAC is present on the terminals of the thermostat
bracket. If removing the thermostat from the wall,
use caution and avoid touching any of the connec-
tor terminals on the wall bracket.
Also, when working with the thermostat dip
switches, use a non−conductive tool and take cau-
tion to avoid making any contact with the circuit
board, its imprinted circuitry and its connector
prongs.
Temperature Display
Display Scale: Fahrenheit or
Celsius user selectable (via DIP switch; see figure 18)
Display range
35°F (2°C) to 99°F (37°C)
. . . . . . . . . . . . .
Display resolution
1°F (1°C)
. . . . . . . . . . . . . . . . . . . . . . . .
Display Accuracy
+/−1°F
. . . . . . . . . . . . . . . . . . . . . . . . . . . .
