Controlling The Heat/Cool Modes Of Operation - Lennox ComfortSense L7742U Programming Manual

Controlling the Heat/Cool Modes of
Operation
Press the screen anywhere − the first press turns on the
backlight.
While in the HOME screen, press MODE field;
repeated presses scroll through all the modes.
AUTO (autochangeover)
thermostat to switch between Heating and
Cooling, whichever mode is dictated by the indoor
temperature. EM
bypasses the first stage of heating (any stage[s] of
heat pump heating) and goes directly to the heat
stage used for maximum heating to more quickly
warm a very cold house.
When the indoor temperature decreases or increases, the
HEATING or COOLING cycle will turn on based on the dis-
played mode. When the HVAC system is on, the informa-
tion display (shown in figure 3) will display one or several
operational messages (listed in the table below). If the out-
Information Displays:
Faults, Errors, and Service Information
TEMP SENSOR ERROR, MEMORY ERROR
CALL FOR SERVICE
NO OUTDOOR SENSOR
REMIND CLEAR SERVICE
REPLACE: MEDIA FILTER; UV LAMP; HUM PAD; METAL INSERT
REMIND RESET
ROUTINE SYS CHECK−UP
REMIND RESET
NO OUTDOOR SENSOR, HUM SENSOR ERROR, HVAC ERROR
DETECTED
REMIND SERVICE
LOW BATTERY
REMIND
506180−01 09/08
mode allows
HEAT (emergency heat)
Top line: fault/error
Bot. line: action
Top line: fault/error
Bot. line: action
Top line: serv. req'd
Bot. line: action
Top line: serv. req'd
Bot. line: action
Top line: fault/error
Bot. line: action
Top line:fault/error
Bot. line: action
door sensor is connected, and is turned on in both installer
and user settings, outdoor temperature will be included in
the displays. The table below summarizes the information
messages.
When the faults, errors, and service information displays
appear, action boxes will appear under the second line en-
tries, REMIND, CLEAR, SERVICE, or RESET. Press the
box to perform the action.
the
Figure 3. Home Screen
Operating Information
SET DATE/TIME
Default DATE/TIME (MON JAN 1 12:00 PM)
HEATING, COOLING, HUMIDIFYING, DE-
HUMIDIFYING, SYSTEM OFF, OUTDOOR
TEMP xxF, INDOOR RH xx%,
MON SEP 24 3:OO PM
SCHEDULE ON, SCHEDULE OFF, WAIT, FAN
ON, FAN CIRC
MON SEP 24 3:OO PM
HOLD SETTING UNTIL
MON SEP 24 3:OO PM
Page 4
[First time start up mes-
sage]
Top line: operation mes-
sages
Bottom line: date & time
Top line: add'l operation
msgs
Bottom line: date & time
PRESS SCHED TO
[Alternating messages
RESUME PROGRAM
during a held schedule]