GENERAL
Relative humidity (RH) is defined as the amount
of moisture in the air at a certain temperature
compared to how much moisture it could hold if
totally saturated. It is expressed as a percentage.
Human beings are fairly sensitive to relative
humidity as it affects the body’s natural ability to
regulate temperature. As the relative humidity
changes, so changes the rate at which
evaporation of moisture on the skin occurs. This
directly affects the body temperature regulating
mechanisms.
Under many conditions of comfort cooling or
heating, the temperature of a conditioned space
can be at a theoretically comfortable level while
the relative humidity of the space is higher than
would normally be acceptable. The results of this
can be inadequate human comfort and moisture
levels in the conditioned space that may promote
mold and mildew growth.
Typically, operating an air conditioning unit during
the cooling season will keep the relative humidity
Unit Connection Diagram
(Dependent Operation)
REMOVE
JUMPER ON S1
& S2 WHEN
OPTIONAL
DEHUMIDISTAT
IS USED
WALL-MOUNTED
DEHUMIDISTAT
(OPTIONAL)
in the space at comfortable levels; however, there
are times during cool or rainy weather when the
air conditioning does not operate often enough to
keep the humidity at a comfortable level.
Oftentimes, homeowners lower the thermostat to
try to compensate for this and cause the air
conditioning equipment to operate. Not only is this
an expensive option, it may be counter
productive. Cool air can hold less moisture and
the relative humidity may increase. This accounts
for the cool clammy feeling under these
circumstances and, left alone, it will further
promote mold and mildew growth when moisture
condenses on cool surfaces.
The whole house dehumidifier, on the other hand,
operates when the regular air conditioning unit is
not operating. When the dehumidistat senses that
the humidity is high it starts the dehumidification
process. The dehumidifier will remove moisture
while NOT OVERCOOLING the space. As stated
above, overcooling is expensive and does not do
the job. When the humidity level is under control,
the dehumidifier stops.
OPERATION
8
S1-DEHUMDKIT
S1-DEHUSTAT
