Controlling The Heat/Cool Modes Of Operation - Lennox L7742U Owner's 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
(autochangeover) mode allows the thermostat to switch
between Heating and Cooling, whichever mode is dictated by
the indoor temperature. EM HEAT (emergency heat)
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 displayed mode. When the
HVAC system is on, the information display (shown in figure 3) will dis-
play one or several operational messages (listed in the table below). If
the outdoor 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
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
through all the modes.
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
boxes will appear under the second line entries, REMIND, CLEAR,
SERVICE, or RESET. Press the box to perform the action.
AUTO
Figure 3. Selecting Mode of Operation
Operating Information
SET DATE/TIME
Default DATE/TIME (MON JAN 1 12:00 PM)
HEATING, COOLING, HUMIDIFYING, DEHUMIDIFYING,
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
ComfortSenset Model L7742U Touch Screen 7−Day Programmable Thermostat
Page 5
[First time start up message]
Top line: operation messages
Bottom line: date and time
Top line: add'l operation msgs
Bottom line: date and time
PRESS SCHED TO
[Alternating messages during
RESUME PROGRAM
a held schedule]