Thermostat Reset; Default Thermostat Settings; Technical Specifications - Lennox ComfortSense L3021H Operation Manual

Thermostat RESET

Under some abnormal conditions, it may be desirable to
reset the thermostat to its default condition. The RESET
button can be used to return the unit to normal operation
after an occurrence such as an electrical storm or power
outage.
The RESET button is an unlabeled, recessed button lo-
cated behind the door on the right−hand side of the thermo-
stat, just below the SETTINGS button. The RESET button
is visible in figure 3. Use a paper clip or small pencil to
press the RESET button. After the RESET button is
pressed, the thermostat settings will return to the defaults
listed in the Default Settings section.

Default Thermostat Settings

Default Thermostat settings are in table 1.
Table 1. Default Thermostat Settings
Mode
Setpoint
Fan
Filter Reminder
Equipment Protection
Timers

Technical Specifications

Thermostat Type
Electronic nonprogrammable thermostat for 1H/1C, heat
pump with electric or gas backup heat source, non−power
robbing applications.
Power Supply Range
18VAC − 30VAC (24VAC nominal), 60Hz
Temperature Display
Display Scale: Fahrenheit or Celsius user selectable (via
DIP switches)
Display range: 35°F (2°C) to 99°F (37°C)
Display resolution: 1°F (1°C)
Display Accuracy: +/−1°F
Temperature Measurement Range
Measurement Scale: Fahrenheit
Measurement Range: 35°F to 99°F
Measurement Resolution: 0.5°F
Measurement Accuracy: +/−1°F
Field Offset: via DIP switches to +/−3°F
Sampling Method: temperature measurements sampled
every 15 seconds. Displayed temperature is the average
of the last four measurements.
506078−01 02/08
Heat
70°F (or 21°C)
Auto
OFF (reminder setting = 0)
reset back to zero
Temperature Setpoint Range
Setting range: 50°F (10°C) to 90°F (32°C)
Setting resolution: 1°F (1°C)
Temperature Control Band
SP+1.5F . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SP+1.0F . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SP+0.5F Y1 off
SP
SP−0.5F Y1 on
(start W1 upstage timer of 30 min.)
SP−1.0F . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SP−1.5F . . . . . . . . . . . . . . . . . . . . . . . . .
(SP = temperature setpoint)
Figure 16. Normal Heat Mode
SP+1.5F . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SP+1.0F . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SP+0.5F emergency heat off
SP
SP−0.5F emergency heat on
SP−1.0F . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SP−1.5F . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
(SP = temperature setpoint)
Figure 17. Emergency Heat Mode
SP+1.5F . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SP+1.0F . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SP+0.5F Y1 on
SP
SP−0.5F Y1 off
SP−1.0F . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SP−1.5F . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
(SP = temperature setpoint)
Figure 18. Cooling Mode
Fan Control
AUTO or ON modes.
Backup Heat Source Selection
Electric or gas furnace, selectable via DIP switch #5 (Aux
or Dual, respectively). See also Thermostat Output sec-
tion.
I/O Relays
All thermostat relays are latching type to minimize power
consumption. See table 2.
Page 6
W1 off
(disable W1 upstage timer)
W1 on . . . . . . .
(without delay)