Technical Specifications; Temperature Setpoint Range; Fan Control - Lennox ComfortSense 3000 Series Operation Manual

Technical Specifications

Thermostat Type
Electronic programmable thermostat for 1-StageHeat/
1-Stage Cool, gas or electric heat, non-heat pump, non-
power robbing applications.
Power Supply Range
18VAC - 30VAC (24VAC nominal), 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 connector terminals
on the wall bracket.
Also, when working with the thermostat dip switches, use
a non-conductive tool and take caution 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
If the Fahrenheit/Celsius display must be changed, use a
plastic, non-conductive tool to push the dip switch to the
right position (see figure 18).
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.

Temperature Setpoint Range

Setting range: 50°F (10°C) to 90°F (32°C)
Setting resolution: 1°F (1°C)

Fan Control

AUTO or ON modes, gas or electric heat compatible via
DIP switches (also see Thermostat Output section).Backup
Heat Source Selection
Electric or gas furnace, selectable via DIP switch #5 (Aux
or Dual, respectively). See also Thermostat Output section.
I/O Relays
All thermostat relays are latching type to minimize power
consumption.
1. HEAT/COOL relay output
2. FAN relay output
3. SERVICE relay input
Equipment Protection Timers
Minimum Compressor OFF time: 5 minutes
Minimum Compressor ON time: 4 minutes
Minimum Furnace ON time: 3 minutes
Minimum furnace cycle time (elapsed time between any
furnace activation and the next furnace activation): 6
minutes.
Minimum elapsed time between any compressor activation
and the next compressor activation: 6 minutes.
NOTE: All protection timers (except the compressor OFF
timer) can be over-ridden if a heating or cooling
demand is initiated or terminated using the UP,
DOWN, HEAT, or COOL buttons.
Equipment Protection Override
Both the minimum compressor OFF timer and the minimum
equipment cycle timer can be over-ridden by pressing
and holding either the HEAT or COOL button down for 4
seconds.
Over-Temperature Protection
Thermal-mechanical switch opens W1 at 93°F+/-6°F.
Filter Reminder
Settings of Off, 1, 3, 6 or 12 (months of fan run time) are
available. When programmed time has elapsed, a FILTER
indicator is displayed.
Maintenance Reminder
Settings of Off, 6 or 12 (months of chronological time)
are available. When programmed time has elapsed, a
maintenance indicator "MAINT" is displayed.
Service Reminder
The SERVICE indicator is displayed only under the following
conditions:
• if the thermostat Y1 terminal has been activated with
24VAC for at least 5 minutes, AND the L terminal is
shorted to the R terminal;
OR
• if the thermostat Y1 terminal has been activated with
24VAC for at least 5 minutes, AND the L terminal is
shorted to the C terminal.
Power Loss/Recovery
Thermostat memory is retained for a minimum of 24
hours during a power loss (includes retention of program
information, HOLD status, programmed temperature
setpoint, heat/cool and fan mode settings, filter reminder
status, maintenance reminder status, and equipment
protection timers). After 24 hours of power loss, programmed
settings will be lost and replaced with default settings.
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