Bryant ZONE PERFECT PLUS ZONEBB2KIT Installation Instructions Manual page 13

To make a humidification selection or change the humidity (hu) set
point, a 2-button keypad press is required. Press SET TIME/TEMP
and FAN buttons simultaneously (indicated on the keypad by the
RH symbol) to enter the humidity mode. Either hu (humidify) or
dhu (dehumidify) will appear on the display. Use the SET
TIME/TEMP buttons to select hu (humidify). Now UP and
DOWN buttons may be used to adjust the value of the humidify set
point to a value between 10 and 45 percent. One of the following
humidification modes may also be selected:
1. Normal Humidify Mode — This is the factory default. This
configuration will bring on the humidifier only in the
heating mode when there is a humidify demand.
2. Fan Humidify Mode — This is selected by pressing FAN
button to turn on FAN icon. This configuration allows a
humidify demand to turn on the fan and humidifier together,
even if there is no heat demand.
3. Auto Humidify — This is selected by pressing MODE
button to turn on AUTO icon. This configuration allows the
rh set point to automatically track and adjust according to
the outdoor air temperature. The set point will automatically
increase or decrease with every 2°F change in outdoor
temperature between 0° to 50°F. To use this feature an
outdoor air sensor must be attached, or an E3 error will
occur.
4. Auto and Fan Humidify — This is selected by pressing both
MODE button and FAN button to turn on AUTO and FAN
icons. This configuration combines both fan humidify and
auto humidify together in bringing on the humidifier when
there is a humidify demand (without any heating demand),
and will automatically track and adjust the rh set point
according to the outdoor air temperature.
5. Humidify Off — This is used to disable the humidify mode.
To turn the humidify function OFF, use DOWN button to
scroll the humidity set point all the way down. The lowest
setting will be 10 percent before off (OF) appears in the
display. When OF is displayed, the humidification mode is
disabled.
To exit humidity setup mode, press END button, or if no buttons
are pressed for 3 minutes, the User Interface will save and exit this
mode returning to normal operation.
→ DEHUMIDIFICATION
Zone Perfect Plus contains a rich set of capabilities for the
enhancement and control of dehumidification, particularly when
used with a variable speed (ICM) blower.
A dehumidification set point(separate from the humidification set
point) can be set to a value between 50 percent and 90 percent
humidity or can be turned off. When the humidity rises above this
set point by 2 percent, the dehumidify output is turned off. When
the humidity falls to 2 percent below this set point, the dehumidify
output turns on, supplying 24vac at its output. This output can be
used to control any 24-vac device which decreases humidity when
its control signal is removed.
When a variable speed blower with a dehumidify input is used
with the system, the dehumidify output can be connected to its
dehumidify input. This connection provides reduced cooling air
flow while dehumidification is needed yielding better moisture
removal from cooling air.
If the system has a 2-speed compressor (as selected by Equipment
Controller DIP switch No. 2) and a PSC blower (as selected by
User Interface Option No. 7), a dehumidify demand will make
compressor operate at high speed only for any cooling demand.
High speed provides better water removal than low speed when a
2-speed compressor is used with PSC blower.
Another selection provides humidity control by operating the
cooling system when cooling is not required. If the humidity rises
above the dehumidification set point, a special dehumidification
routine is executed. As long as zone temperatures are not more
than 3°F below their cooling set points, a dehumidify demand will
turn on the cooling equipment but will limit its ON time to no more
than 7 minutes at a time.
Finally, OUT zones are used to their maximum capability. When
a zone is set to OUT it can be used to help remove humidity by
cooling it as much as possible. When there is a dehumidify demand
and a zone set to OUT, its damper is fully opened, and it can be
cooled down to as low as 70°F. If it reaches 70°F its damper will
close.
When all zones are set to OUT the house or business is in vacation
mode. The cooling equipment will come on either to maintain the
house or business below 85°F or to maintain the dehumidify set
point by cooling the house or business down to as low as 70°F.
This is a valuable feature for unoccupied homes or businesses in
hot and damp climates.
IMPORTANT: It may be advisable to configure the dehumidify
control as part of the system installation process. Following is a
brief description of the dehumidify setup process. It is also covered
in the Owner's Manual.
There are 4 selections for dehumidification in the cooling mode:
1. Normal Dehumidify
2. Cool to Dehumidify
3. Vacation Dehumidify
4. OFF
To make a dehumidification selection or change the dehumidify
(dhu) set point, a 2-button keypad press is required. Press SET
TIME/TEMP and FAN buttons simultaneously (indicated on the
keypad by the RH symbol) to enter the humidity mode. Either hu
(humidify) or dhu (dehumidify) will appear on the display. Use
SET TIME/TEMP buttons to select dhu (dehumidify). Now UP
and DOWN buttons may be used to adjust the value of the
dehumidify set point to a value between 50 and 90 percent. One of
the following dehumidification modes may also be selected:
The dehumidify relay is a reverse logic relay. When the humidity
level is above the dehumidify set point, the DHUM relay is off.
When the humidity level is below the dehumidify set point, the
DHUM relay is on.
When in the dehumidification mode, the following can be selected:
1. Normal Dehumidify Mode — This is the factory default.
The dehumidification feature is designed for use with
variable speed indoor equipment. When normal dehumidify
is selected, the compressor will not turn on without a
cooling demand. If a dehumidify demand exists while
cooling, the dehumidify output will be active (i.e. 24vac
removed from DHUM).
2. Cool to Dehumidify Mode — This is selected by pressing
the MODE button to turn on the COOL icon. In selecting
this mode, you are controlling to the rh set point. The cool
to dehumidify feature allows the system to turn on the air
conditioning (i.e. Y output) as needed to try to reach the
selected set point. The equipment will be cycled for
approximately 7 minutes on, and 8 minutes off to control
the humidity. Zone temperatures may be over conditioned
up to 3°F when trying to lower the humidity level. If a
cooling demand exists at the same time as a dehumidify
demand, then the equipment will run until the cooling
demand is satisfied.
3. Vacation Dehumidify — This is selected by selecting the
above cool to dehumidify function (turning on COOL icon),
then exit the humidity program by pressing END key. Next,
press HOLD, OUT, and ALL ZONE buttons in that order to
program all zones to an unoccupied status. The air condi-
tioning equipment will now turn on as needed to control to
the selected dehumidification set point, but it will not drop
the indoor temperature lower than 70°F.
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