Dehumidification - Lennox ComfortSense 7000 Series Programming And Application Manual

Dehumidification

INSTALLER SETTINGS
Dehumidification (removing moisture from air) can occur
only when the thermostat is in cool mode. When a dehu-
midification demand is present, a dehumidification signal
(0VAC − open circuit) is present at the D terminal. This is
used to reduce the speed of the indoor blower during dehu-
midification. At the same time, the Y1 and Y2 (if available)
terminals become activated with 24VAC. The H terminal is
inactive (0VAC − open circuit) during dehumidification.
NOTE − The D terminal is ALWAYS activated (24VAC)
when the thermostat is in HEAT or OFF mode; it is only in-
active (0VAC − reverse logic) during dehumidification.
Dehumidification adjustment will change the relative hu-
midity (RH) setting between 45 to 60% RH (default setting
is 50% RH). The lower the number, the more humidity will
be removed from the air.
HUMIDITY SETTING default OFF.
Installer settings must be turned on before the user
will have control over the humidity.
The mode selected determines how the user can adjust
the relative humidity (RH). The installer settings include
BASIC, PRECISION, HUMIDITROL, and OFF.
Dehumidification Modes
In BASIC mode, dehumidification occurs if these condi-
tions are met and signals are present at specific terminals:
S
dehumidification has been enabled on installer set-
tings, and
S
the unit is in COOL mode, and
S
dehumidification demand exists (RH above setpoint),
and
S
cooling demand exists (Y1 energized).
In PRECISION mode, dehumidification occurs if all BASIC
conditions are true, except cooling demand may or may
not be present. Maximum over cool from cooling set point
is 2ºF.
HUMIDITROL mode requires:
S
outdoor sensor must be installed and setup
S
dehumidification has been enabled on installer set-
tings, and
S
the unit is in COOL mode, (or if in AUTO, there has
been at least one thermostat cooling call made prior to
the dehumidification demand), and
S
a dehumidification demand exists (RH above set-
point), and
S
outdoor temperature is below 95°F, and
S
indoor temperature is above 65°F, and
S
the room temperature meets Humiditrol adjustment
parameters as follows:
MAX − Indoor temp > 2°F above heating setpoint
D
MID − Indoor temp >
D
MIN − Indoor temp > 2°F below cooling setpoint
D
HEAT SETPOINT+COOL SETPOINT
2
Scroll to HUMIDITY SETTINGS; press ENTER. Press the
box below DEHUMIDIFY.
HUMIDITY MODE
HUMIDIFY DEHUMIDIFY
|
Use up/down arrows to scroll to BASIC or PRECISION;
press ENTER.
DEHUM MODE SETTING
DEF(OFF) PRECISION
Default setting is 50% RH. Use up/down arrows to change
the %RH; press SAVE.
DEHUM SETPOINT
DEFAULT (5O%)
The AUX setting is used when a whole home dehumidifier
is used for dehumidification. This requires:
S
whole home dehumidifier has been wired to thermo-
stat per dehumidifier installation instructions, and
S
dehumidification has been enabled on installer set-
tings, and
S
the unit is in COOL mode, (or if in AUTO, there has
been at least one thermostat cooling call made prior to
the dehumidification demand), and
S
a dehumidification demand exists (RH above set-
point).
USER SETTINGS
BASIC, PRECISION, HUMIDITROL, AUX If installer
has set up for BASIC, PRECISION, HUMIDITROL or
AUX, this adjustment controls the relative humidity (RH)
between 45 and 60% (default 50%).
Scroll to HUMIDITY SETTINGS; press ENTER. Press the
box below DEHUMIDIFY.
HUMIDITY MODE
HUMIDIFY DEHUMIDIFY
|
Use up/down arrows to change the humidity setpoint (be-
tween 45 and 60%); press SAVE.
DEHUM SETPOINT
DEFAULT (5O%)
OFF if OFF selected in installer settings for both humidify
and dehumidify, this message appears when HUMIDITY
SETTING is pressed:
HUMIDITY MODES OFF
If OFF is selected by the installer settings for DEHUMID-
IFY but HUMIDIFY is on, the humidification menu appears
(this setpoint adjust has NO effect on dehumidification):
HUM SETPOINT
DEFAULT (45%)
Page 15 ComfortSenset Touch Screen Thermostat
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45%
|
45%
4O%