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which give off heat. If the CCB1 is installed directly above
the indoor thermostat, the humidity sensor calibration will
be thrown off. If the CCB1 is installed directly above the
indoor thermostat, it should be relocated to the side of the
thermostat. Refer to CCB1 installation instructions.
Other Conditions Which Adversely Affect
CCB1 Performance
Blower speed selection can adversely affect CCB1
performance. Higher blower speeds should be selected to
provide maximum sensible cooling, while lower blower
speeds should be selected to provide maximum humidity
removal. Refer to CBX32MV and CCB1 installation
instructions.
It is recommended that the indoor blower be left in AUTO
mode at all times. During dehumidification mode, the
indoor coil and drain pan may become saturated with
moisture. If the indoor blower is left in ON mode, much of
that moisture can be re-evaporated into the living space
between thermostat demands. This can create a constant
demand for humidity removal and may cause extended
compressor run times. Refer to table 7 for jumpers per
application. CBX32MV units manufactured January 2002
and later, will have factory installed jumpers. Remove
jumpers not used.
TABLE 7
JUMPERS REQUIRED
Without CCB1
Humidity
Control
Heat Pump
Single Speed
DS to Y1 and
Y1 to Y2
Two Speed
DS to Y1
Condensing
Unit
Single Speed
DS to Y1 and
Y1 to Y2 and
O to R
Two Speed
DS to Y1 and
O to R
With CCB1 Hu-
midity
Control
Heat Pump
Single Speed
Y1 to Y2
Two Speed
None
Condensing
Unit
Single Speed
Y1 to Y2 and
O to R
Two Speed
O to R
The CCB1 may become indefinitely latched in the
dehumidification mode when power to the unit is turned off.
This condition can be caused by turning off power while
dehumidification demand is present, then turning on power
when dehumidification demand is satisfied. If the CCB1
becomes stuck in this manner, it can be reset by removing
thermostat demand then moving the CCB1 slide switch all
the way down and back up to its setpoint.
How to unlatch CCB1
1− Force a cooling demand by setting thermostat to COOL
mode and by moving thermostat lever to lowest
position.
2− Move CCB1 slide control down to 40% relative
humidity. CCB1 lights should come on.
3− Now, move CCB1 slide control back up to 60% relative
humidity. The lights should go off.
4− Remove thermostat demand by moving thermostat
lever to cycle unit off.
Applications with the Efficiency
Plus
CCB1 humidity control
create different CFM volumes. For example, during a
first−stage cooling call (two−speed outdoor unit) with no
demand from the CCB1, the air volume is 40% of the
COOL
jumper selection. For a normal
COOL
(Pin #2 setting for
CBX32MV−036), the CFM is 1125; the reduced speed is
450 CFM (1125 x 40% = 450). This arrangement provides
for additional dehumidification during first stage cooling.
See tables 10 and 11 for various scenarios concerning use
of the CCB1 humidity control and the CBX32MV series unit.
B−SignatureStat
t
or ComfortSense
®
7000
The reference thermostats can be installed in place of the
indoor thermostat. The thermostat monitors indoor
humidity conditions and creates a dehumidification
demand in response to indoor humidity just as it creates a
cooling demand in response to indoor temperature. The
SignatureStat adjusts compressor speed and indoor
blower speed to maintain humidity at a comfortable level.
Principles of Cooling with Drier Air
The humidity comfort range for humans is between 40%
and 60% relative humidity (RH). 50% RH is the
recommended initial setpoint until personal comfort level is
established. The personal comfort level will vary with
humidity as with temperature. For example, if air at 75
°
F
and 50% RH is changed to 60% RH, the air will feel" much
warmer. Likewise, if the air is reduced to 40% RH, it will
feel" much cooler.
Even when inactive, the body evaporates a large amount of
moisture away from the skin. This evaporation produces a
cooling effect (during wintertime this phenomenon is called
wind-chill"). Dry air is capable of absorbing more moisture
away from the skin thereby increasing the cooling effect.
When the thermostat senses that the indoor humidity level
is above the control setpoint, the control places the
CBX32MV and outdoor unit in a dehumidification mode.
To produce drier air, the CBX32MV will slow down the
speed of the air crossing the indoor coil. Because the air is
moving much slower than normal, the indoor coil is allowed
more time to remove moisture from the air (a higher
percentage of the air passing over the coil is cooled to its
dew point removing more moisture). At the same time the
two-stage outdoor unit will switch to high-speed to produce
a colder indoor coil. The colder indoor coil and slower
moving air combine to produce drier supply air.
