Ask
yourself, “if my house had to take a
complete physical examination, would the air inside pass
the test…get a clean bill of health”? Maybe
someone should propose a Medicare program for houses.
Come to think of it, to some extent, maybe we do. It’s
called “Preventative Maintenance”…but
that’s only for HVAC systems, not the entire house.
Previously
we have discussed the role
of the heating and cooling systems as they relate to
thermal comfort. Today, we focus on the 3rd element
of a “Climatemakers Total Comfort System”:
Humidity control.
While
it is a given that most homes
have some type of system to add heat to the air in
winter and to remove excessive heat from the air in
summer, what most people fail to realize is that temperature
is not the only factor in personal comfort; that the
humidity level i.e., also plays a critical role.
Two
basic types of moisture problems may
exist in a home depending on the season of the year.
Humidity levels in your home can be either too low
(winter) or too high (summer). In either case, problems
can result.
Insufficient moisture (winter).
Warm
air can hold more moisture than cool air. So
the relative humidity (RH) of the air changes as the temperature of
the air changes, even though the actual amount of
moisture in the air does not change.
As
winter sets in, a heating system begins to dry
out the air inside your home. The warm, dry air,
acts like a giant sponge, soaking up moisture from
everything it touches.
For
family members, it can cause
among other things, dry skin and hair, itching and
chapping. Mucous membranes in nose and throat dry out,
increasing your discomfort and susceptibility to colds
and increased respiratory problems. With low humidity
levels, body moisture evaporates so quickly that you
feel chilled even at higher thermostat settings.
Your
home suffers too. Parched,
thirsty air, literally sucks the moisture out of your
home's woodwork and furnishings, leaving them cracked
or dried out and excessive static electricity in clothing
and carpets cause additional discomfort and frustration.
There’s no question about it; air that's too
dry, can take on your family and your house.
Solution:
Fortunately,
if you have a problem of insufficient
humidity, it can usually be easily resolved. Properly
sized and installed, a whole-house humidifier can easily
and automatically correct the problems of insufficient
humidity by maintaining a comfortable, healthy humidity
level throughout the home which is usually between
35 and 45% relative humidity (RH).
Although
there are many brands to choose
from, basically there are only two types of humidifiers.
Your choice is important. Better humidifiers are equipped
with a drain that removes unused water from within
the humidifier either continuously, or when it is turned
off. The two types are:
*
Power or Direct Humidifier
*
Bypass Humidifier
The
Power Humidifier has
a built-in fan which pulls heated air from the warm
air (supply) side of the furnace, pushes it across
a water panel or media where the warm air picks up
moisture, and then is distributed throughout the home.
A
Bypass Humidifier usually has
no fan. A portion of the heated air from the supply
duct, is diverted (bypasses) across a water panel or
media, and then returned to the air in the return duct
of the furnace. This pre-humidified air is then heated
by the furnace and delivered to the conditioned space.
Both
types of humidifiers are capable
of providing the right amount of humidity. We can advise
you which one is best suited for your home.
A
control that senses and regulates the
humidity level by turning the humidifier on and off
is called a Humidistat. It's usually mounted either
next to the thermostat, or in the main return air duct
of the furnace.
Excessive moisture (summer):
Excessive
moisture is, at best, a
nuisance; at worst, the source of critical structural
failure. It can cause a number of undesirable conditions--some
obvious, but others not always evident or visible.
Correcting problems of too much moisture in the air
is also far more complex than insufficient moisture
and can be one of the most insidious .
In
many cases it also causes (or
contributes to) a range of health problems--from minor
thermal comfort complaints to full-blown allergy attacks.
One of the problems associated with excessive moisture
that has been getting a lot of public attention lately
is mold…which must be prevented to achieve good
indoor air quality.
The
presence of excessive humidity can
range from possibly energy-related problems (improper
air conditioner sizing; broken exhaust fan) to a host
of more subtle and complex structural problems and
correcting them usually requires the services of professionals
skilled in construction analysis. Neglecting moisture
and water problems can lead to material damage and
possibly even a range of health problems.
It’s
your family’s health and it is you, the homeowner,
who pays the bill.
Next time, Indoor Air Pollution. |
