U.S. patent application number 10/102184 was filed with the patent office on 2003-09-25 for indoor air treatment system with hepa filtration.
Invention is credited to Brumett, Anthony Lee.
Application Number | 20030177777 10/102184 |
Document ID | / |
Family ID | 27804307 |
Filed Date | 2003-09-25 |
United States Patent
Application |
20030177777 |
Kind Code |
A1 |
Brumett, Anthony Lee |
September 25, 2003 |
INDOOR AIR TREATMENT SYSTEM WITH HEPA FILTRATION
Abstract
An air treatment system includes a housing that defines an
interior cavity. The interior cavity has a supply-air flow path and
a stale-air flow path. A HEPA filter is positioned along the
supply-air flow path to filter supply air. A heat recovery core is
positioned downstream from the HEPA filter along the supply-air
flow path. The heat recovery core is positioned between the
supply-air flow path and the stale-air flow path to exchange heat
between the supply air and stale air. An evaporator is positioned
downstream from the heat recovery core along the supply-air flow
path to remove heat from the supply air. An ultraviolet light is
positioned downstream from the evaporator along the supply-air flow
path to irradiate the supply air with ultraviolet light. A
condenser is positioned downstream from the ultraviolet light to
reintroduce the heat removed from the supply air by the
evaporator.
Inventors: |
Brumett, Anthony Lee;
(Washington, IN) |
Correspondence
Address: |
Charles P. Schmal, Esq.
Woodard, Emhardt, Naughton, Moriarty and McNett
Bank One Center/Tower
111 Monument Circle, Suite 3700
Indianapolis
IN
46204-5137
US
|
Family ID: |
27804307 |
Appl. No.: |
10/102184 |
Filed: |
March 19, 2002 |
Current U.S.
Class: |
62/264 ;
62/259.1; 62/410; 62/428 |
Current CPC
Class: |
Y02B 30/56 20130101;
F24F 2011/0002 20130101; F24F 8/22 20210101; F24F 12/006 20130101;
F24F 3/153 20130101; F24F 8/158 20210101; F24F 8/10 20210101 |
Class at
Publication: |
62/264 ;
62/259.1; 62/410; 62/428 |
International
Class: |
F25D 023/12; F25D
023/00; F25D 017/04; F25D 017/06 |
Claims
What is claimed is:
1. An air treatment system, comprising: a housing defining an
interior cavity, said interior cavity having a supply-air flow path
and a stale-air flow path; a high efficiency particulate air filter
positioned in said interior cavity of said housing along said
supply-air flow path to filter supply air; a heat recovery core
positioned downstream from said high efficiency particulate air
filter along said supply-air flow path, said heat recovery core
being positioned in said interior cavity between said supply-air
flow path and said stale-air flow path to exchange heat between
said supply air and stale air; an evaporator positioned downstream
from said heat recovery core along said supply-air flow path to
remove heat from said supply air; an ultraviolet light positioned
downstream from said evaporator along said supply-air flow path to
irradiate said supply air with ultraviolet light; and a condenser
positioned downstream from said ultraviolet light along said
supply-air flow path to reintroduce said heat removed from said
supply air by said evaporator.
2. The system of claim 1, wherein said housing defines a fresh air
intake port to supply fresh air to said supply-air flow path.
3. The system of claim 2, wherein said housing defines a
recirculation air intake port to supply recirculated air to said
supply-air flow path.
4. The system of claim 3, further comprising a baffle provided
along said supply-air flow path in said housing, said baffle being
postionable to alternately close said fresh air intake port and
said recirculation air intake port.
5. The system of claim 4, further comprising a motor coupled to
said baffle to position said baffle.
6. The system of claim 1, further comprising a charcoal filter
positioned upstream from said high efficiency particulate air
filter along said supply-air flow path in said interior cavity to
filter said supply air.
7. The system of claim 1, wherein said housing includes: a
stale-air chase positioned upstream from said heat recovery core
along said stale-air flow path; and a tempered-air chase positioned
downstream from said condenser along said supply-air flow path.
8. The system of claim 7, wherein said stale-air chase and said
tempered-air chase parallelly extend the entire length of one side
of said housing.
9. The system of claim 1, wherein said housing has a rectangular
cross sectional shape.
10. The system of claim 1, further comprising a compressor
positioned in said interior cavity of said housing, said compressor
being operatively coupled to said evaporator and said
condenser.
11. The system of claim 1, further comprising: a supply air fan
positioned in said interior cavity to move said supply air along
said supply-air flow path; and a stale air fan positioned in said
interior cavity to move said stale air along said stale-air flow
path.
12. The system of claim 11, wherein: said supply air fan is
positioned downstream from said condenser along said supply-air
flow path; and said stale air fan is positioned downstream from
said heat recovery core along said stale-air flow path.
13. The system of claim 1, further comprising an electrical panel
positioned in said housing to supply electricity.
14. The system of claim 1, further comprising a drain pan
positioned in said interior cavity below said evaporator to collect
condensation from said evaporator.
15. The system of claim 1, further comprising a forced air furnace
operatively coupled to said housing through ductwork.
16. The system of claim 15, wherein said ductwork includes: a
supply air duct to exhaust heated air from said furnace; and a
tempered air duct positioned downstream from said condenser along
said supply-air flow path, said tempered air duct coupled to said
supply air duct to supply said supply air to said supply air
duct.
17. The system of claim 15, wherein said furnace is constructed and
arranged to operate continuously.
18. The system of claim 1, wherein said high efficiency particulate
air filter is constructed and arranged to filter particulates at
least 0.3 microns in diameter with at least 99.97% efficiency.
19. An air treatment system, comprising: a housing defining an
interior cavity, said interior cavity having a supply-air flow path
and a stale-air flow path; said housing including a stale air chase
for supplying stale air to said stale-air flow path; said housing
including a tempered air chase for exhausting supply air from said
supply-air flow path, wherein said stale air chase and said
tempered chase parallelly extend an entire length of one side of
said housing; said housing defining a fresh air intake and a
recirculation air intake; a baffle provided along said supply-air
flow path in said housing, said baffle being positionable to
alternately close said fresh air intake and said recirculation air
intake; a charcoal filter positioned downstream from said fresh air
intake and said recirculation air intake along said supply-air flow
path in said interior cavity to filter said supply air; a high
efficiency particulate air filter positioned downstream from said
charcoal filter along said supply-air flow path to filter said
supply air; a heat recovery core positioned downstream from said
high efficiency particulate air filter along said supply-air flow
path, said heat recovery core being positioned between said
supply-air flow path and said stale air flow path to exchange heat
between said supply air and said stale air; an evaporator
positioned downstream from said heat recovery core along said
supply-air flow path to cool said supply air; a drain pan
positioned in said interior cavity to collect condensation from
said evaporator; an ultraviolet light positioned downstream from
said evaporator along said supply-air flow path to irradiate said
supply air with ultraviolet light; a condenser positioned
downstream from said ultraviolet light along said supply-air air
flow path to heat said supply air; a supply air fan positioned
downstream from said condenser along said supply-air flow path to
exhaust said supply air into said tempered chase; a stale air fan
positioned downstream from said heat recovery core along said stale
air flow path to move said stale air; a compressor positioned in
said interior cavity of said housing, said compressor being
operatively coupled to said evaporator and said condenser; and an
electrical panel positioned in said housing to supply electricity
to the system.
Description
BACKGROUND OF THE INVENTION
[0001] The present invention generally relates to indoor air
treatment systems, and more specifically, but not exclusively,
concerns a mechanical and natural process dehumidifier with a
compact construction that incorporates a heat recovery ventilation
system that utilizes a high efficiency particulate air (HEPA)
filter and an ultra-violet sanitation system.
[0002] Indoor air quality has become an increasing concern for new
and newly remodeled home owners. Newer model homes over the past
couple of decades have become more energy efficient and practically
airtight.
[0003] Life inside today's airtight homes generates both moisture
and pollutants. Maintaining an ideal humidity in the home can be
needed for optimum health. In order to create a comfortable living
space, the humidity level in a home should be approximately 40-55%.
When humidity levels are less than 40% or more than 60%, pollutant
levels rise dramatically. This will cause bacteria, viruses, fungi,
mites, respirator infections, allergic rhinitis and asthma,
chemical interactions, and ozone production. With today's tighter
homes, too much humidity during all seasons can be problematic. For
example, excessive moisture can cause the sweating/water drops to
develop on windows and doorjambs. This condition is a major health
concern and can prematurely deteriorate the windows and doorjambs.
Areas of excessive moisture are also breeding grounds for mold,
mildew, fungi, dust mites and bacteria. For example, black spots
may form on the walls of humid homes, which indicate mildew growth.
Mold spores and dust easily become airborne and circulate freely
throughout the house, possibly causing a range of illnesses and
allergic reactions.
[0004] In addition to excessive moisture and biological
contaminants, appliances that utilize combustion have the potential
for allowing gases such as carbon monoxide and other pollutants, to
escape into the air. Some common sources may include gas ranges,
water heaters, unvented space heaters, leaky chimneys, and wood
burning appliances. Today's homes have such high levels of negative
pressure (because of exhausting appliances and fans in the home),
that even a perfectly good chimney or appliance can be back
drafted. Even breathing can add to the problem when carbon dioxide
reaches excessive levels. Most building materials used today are
treated with many harmful toxins that produce off gases that slowly
leak into the home for many years. In addition, household cleaning
products can generate large amounts of pollutants, and there is
also a concern about radon seeping from the ground which may cause
some health problems.
[0005] In a poor attempt to alleviate these problems, ventilation
fans have been installed into rooms of homes, such as bathrooms, in
order to draw stale air containing moisture and/or pollutants out
of the home. However, operating such a fan reduces the overall
energy efficiency and creates a severe negative pressure within the
home. For instance, with an average run time of 20 minutes for a
bathroom fan, approximately 2000 cubic feet of air is drawn out of
the house. Replacement air is air drawn from outside the house and
is unconditioned and unfiltered. This replacement air comes from
the paths of least resistance, such as leaky doors and windows,
chimneys, water heater vents, gas appliance vents, and attached
garage. The replacement air must then be heated or cooled in order
to match the inside air temperature. Further, this replacement air
can worsen the air quality inside the home. During operation of the
ventilation fan, when the humidity outside is greater than the
inside humidity, humidity levels inside the home may in fact be
increased to an uncomfortable level.
[0006] Portable air filters have been used to remove particulates,
such as pollen and mold, from the air. While some of these portable
filters advertise that they use a "HEPA filter", in reality these
filters are not true HEPA filters because they are not large enough
to be at least 99.97% efficient in removing particles of at least
0.3 microns in diameter. With these types of inefficient filters,
pollutants such as smoke, dust and bacteria can remain in the air.
Another problem faced with portable air filtration systems is that
such systems can only clean the air in limited areas of a
house.
[0007] Therefore, there has been a need for an energy efficient,
home air handling system that can be easily installed and that can
maintain the relative humidity of a home at a comfortable level
while at the same time, reducing the amount of pollutants in the
air.
SUMMARY OF THE INVENTION
[0008] One form of the present invention concerns a unique air
treatment system. The system includes a housing that defines an
interior cavity. The interior cavity has a supply-air flow path and
a stale-air flow path. A HEPA filter is positioned in the interior
cavity of the housing along the supply-air flow path in order to
filter supply air. A heat recovery core is positioned downstream
from the HEPA filter along the supply-air flow path. The heat
recovery core is positioned in the interior cavity between the
supply-air flow path and the stale-air flow path to exchange heat
between the supply air and stale air. An evaporator is positioned
downstream from the heat recovery core along the supply-air flow
path to remove heat from the supply air. An ultraviolet light is
positioned downstream from the evaporator along the supply-air flow
path to irradiate the supply air with ultraviolet light. A
condenser is positioned downstream from the ultraviolet light along
the supply-air flow path to reintroduce the heat removed from the
supply air by the evaporator.
[0009] Another form of the present invention concerns a unique air
treatment system. The system includes a housing that defines an
interior cavity. The interior cavity has a supply-air flow path and
a stale-air flow path. The housing includes a stale air chase for
supplying stale air to the stale-air flow path and a tempered air
chase for exhausting supply air from the supply-air flow path. The
stale air chase and the tempered chase parallelly extend the entire
length of one side of the housing. The housing defines a fresh air
intake and a recirculation air intake. A baffle is provided along
the supply-air flow path in the housing, and the baffle is
positionable to alternately close the fresh air intake and the
recirculation air intake. A charcoal filter is positioned
downstream from the fresh air intake and the recirculation air
intake along the supply-air flow path in the interior cavity to
filter the supply air. A high efficiency particulate air filter is
positioned downstream from the charcoal filter along the supply-air
flow path to filter the supply air. A heat recovery core is
positioned downstream from the high efficiency particulate air
filter along the supply-air flow path. The heat recovery core is
positioned between the supply-air flow path and the stale air flow
path to exchange heat between the supply air and the stale air. An
evaporator is positioned downstream from the heat recovery core
along the supply-air flow path to cool the supply air. A drain pan
is positioned in the interior cavity to collect condensation from
the evaporator. An ultraviolet light is positioned downstream from
the evaporator along the supply-air flow path to irradiate the
supply air with ultraviolet light. A condenser is positioned
downstream from the ultraviolet light along the supply-air flow
path to heat the supply air. A supply air fan is positioned
downstream from the condenser along the supply-air flow path to
exhaust the supply air into the tempered chase. A stale air fan is
positioned downstream from the heat recovery core along the stale
air flow path to move the stale air. A compressor is positioned in
the interior cavity of the housing, and the compressor is
operatively coupled to the evaporator and the condenser. An
electrical panel positioned in the housing to supply electricity to
the system.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is a front, cross-sectional view of an air treatment
unit according to one embodiment of the present invention.
[0011] FIG. 2 shows a perspective view of the FIG. 1 system.
[0012] FIG. 3 shows a fragmentary cutaway view of a heat recovery
core used in the FIG. 1 unit.
[0013] FIG. 4 shows a front sectional view of the housing for the
FIG. 1 unit.
[0014] FIG. 5 shows a first sectional side view of the FIG. 4
housing.
[0015] FIG. 6 shows a second sectional side view of the FIG. 4
housing.
[0016] FIG. 7 shows a rear sectional view of the FIG. 4
housing.
[0017] FIG. 8 shows a diagram illustrating ductwork used to attach
the FIG. 1 unit to a forced air furnace having a blower that runs
continuously.
[0018] FIG. 9 shows the ductwork installation of the FIG. 1 unit
when the forced air furnace is designed to run the blower
intermittently.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0019] For the purposes of promoting an understanding of the
principles of the invention, reference will now be made to the
embodiments illustrated in the drawings and specific language will
be used to describe the same. It will nevertheless be understood
that no limitation of the scope of the invention is thereby
intended, such alterations and further modifications in the
illustrated device, and such further applications of the principles
of the invention as illustrated therein being contemplated as would
normally occur to one skilled in the art to which the invention
relates.
[0020] As shown in FIGS. 1-2, an air treatment unit 100 according
to one embodiment (among others) of the present invention includes
a number of air treatment components housed in a single unit. The
unit 100 includes a housing 102 for enclosing and supporting the
various components. The housing 102 has a compact, rectangular
cross-sectional shape such that the unit 100 can be easily
installed in diverse operational environments, such as basements,
crawl spaces and attics. The housing 102 includes an outer shell
104 and inner support walls 106 that separate various inner
cavities 108. As shown in FIG. 1, the housing 102 has a generally
rectangular shape with a first end 110 and a second end 111. At the
first end 110 of the housing 102, a first end wall 112 defines a
fresh air passageway 114 through which fresh air is introduced to
the unit 100. A recirculation air passageway 116 is defined in a
first side wall 118 of the housing 102 that is adjacent to the
first end wall 112 and opposite a second side wall 119. As should
be appreciated, the positions of the fresh air passageway 114 and
the recirculation air passageway 116 can be swapped such that the
first end wall 112 defines the recirculation air passageway 116 and
the first side wall 118 defines the fresh air passageway 114.
[0021] In the housing 102, the unit 100 has a baffle 120 that is
pivotally attached to an electric motor 122 for alternately closing
the fresh air passageway 114 and the recirculation air passageway
116. The fresh air and recirculated air can be mixed or alternately
selected by the baffle 120 to form supply air for the unit 100. As
should be appreciated, the baffle 102 can be actuated with other
types of mechanisms, such as by using mechanical linkages,
pneumatic motors, and hydraulic motors, to name a few. Downstream
from the baffle 120, the unit 100 includes a charcoal filter 124
for removing carbon-based chemicals from the air, such as noxious
gases. The unit 100 further includes a HEPA filter 126, which is
located downstream from the charcoal filter 124. The HEPA filter
126, according to the present invention, is a "true" HEPA filter
that is able to filter particles 0.3 microns in diameter with at
least 99.97% efficiency. When describing the present invention,
"HEPA filter" is defined as a filter that is able to filter
particulates at least 0.3 microns in diameter with at least 99.97%
efficiency. This definition should not be confused with alleged
"HEPA filters" that do not filter with such efficiency. Build up of
contaminants in the unit 100 can disrupt air circulation and reduce
the operational efficiency of the unit 100. Having the charcoal
filter 124 and the HEPA filter 126 located upstream from the
remaining components of the unit 100, reduces the amount of
particulates that can contaminate the rest of the unit 100.
[0022] To improve energy efficiency, the unit 100 includes a heat
recovery core 128, which transfers heat between the supply air and
stale air in the home such that that supply air is heated or cooled
to match the building air temperature. As shown, the heat recovery
core 128 is oriented at an angle relative to the side walls 118,
119. In the illustrated embodiment, the heat recovery core 128 is
an air to air heat exchanger. The housing 102 defines a stale air
inlet port 130 through which the stale air from the house is
supplied to the unit 100. The heat recovery core 128 exchanges
energy between the stale air from the stale air inlet port 130 and
the air from the HEPA filter 126. A magnified view of an example of
the heat recovery core 128 is illustrated in FIG. 3. As shown, the
heat recovery core 128 includes pairs of alternating air channels
302. Conductive walls 304 of the channels 302 conduct the heat
between the two different airflows. In one embodiment, the walls
304 are made of aluminum. As should be appreciated, the heat
recovery core 128 can be made of different material and/or the
walls 304 can be constructed in other manners than the one
shown.
[0023] Referring again to FIGS. 1-2, downstream from the heat
recovery core 128, the unit 100 has an evaporator 134, which is
used to cool the in-flowing supply air and reduce the humidity in
the supply air. As shown, the evaporator 134 is positioned at an
angle to match the orientation of the heat recovery core 128. The
evaporator 134 cools the air in order to reduce the humidity of the
air. By angling the evaporator 134, any condensation formed on the
evaporator can run into a drip pan 136. A drain 137 is formed in
the pan 136 so that the collected water can be removed from the
unit 100.
[0024] An ultraviolet (UV) light 138 is positioned between the
evaporator 134 and a condenser 140 in order to irradiate the
cooled, dehumidified supply air from the evaporator 134. The UV
light 138 destroys bio-aerosols, such as bacteria, mold, mildew and
toxins that can be found in the air. Due to the presence of water,
organisms can grow in the area around the evaporator 134 and the
condenser 140. The UV light 138 is positioned to destroy these
organism on the evaporator 134 and the condenser 140. Further,
positioning the UV light 138 downstream from the evaporator 134
cools the UV light 138, which can extend the operational life of
the UV light 138. The heat removed by the evaporator 134 is
reintroduced into the air through the condenser 140, which is
located downstream from the evaporator 134 and the UV light 138.
The condenser 140 and the evaporator 134 form a heating/cooling
circuit with a compressor 142 through tubing 144. As should be
appreciated, auxiliary evaporators and/or condensers, which are
coupled to the compressor 142, can be positioned outside the
housing 102. Blowers 146, 148 circulate air through the unit 100.
Located at the second end 111 of the unit 100, the tempered air
blower 146 draws the air from the condenser 140. Exhaust blower
148, which is located downstream from the heat recovery core 128,
draws the stale air across the heat recovery core 128. Electric
panel 150 which is located above compressor 142 contains the
electrical controls and other electrical components that are used
to operate the unit 100, such as the UV light 138, the electric
motor 122, the compressor 142, and the blower fans 146, 148.
[0025] As shown in FIG. 2, the housing 102 includes a pair of
chases 202, 204 that extend from the first end 110 to the second
end 111 of the unit 100. The stale air chase 202 supplies the stale
air to the heat recovery core 128 through the stale air inlet port
130. The tempered air chase 204 receives tempered air from the
tempered air blower 146 through a tempered-air port 205 formed in
the housing 102. By parallelly extending the entire length of the
housing 102, the chases 202, 204 can be retrofitted to numerous
types of household installations. Ductwork connections can be
formed at any position along the entire length of the chases 202,
204 by simply cutting an opening for the ductwork in the chases
202, 204. The housing 102 at first end 112 defines a stale air
exhaust port 206 through which the stale air is exhausted from the
unit 100 during operation. It should be appreciated that the stale
air exhaust port 206 can also be formed in the second side wall
119.
[0026] Details of the housing 102, which is used to support the
various components of the unit 100, are illustrated in FIGS. 4-7.
As should be appreciated the construction of the housing 102 allows
for the unit 100 to have a compact construction along with
flexibility in attaching ductwork to the unit 100. The housing 102
has walls 104, 106 that define the various cavities 108 (FIG. 2) in
which the components of the unit 100 are positioned. As illustrated
in FIG. 4, a central wall 404 along with a charcoal filter support
ridge 406 define a baffle cavity 408 in which the baffle 120 is
able to pivot. The charcoal filter support ridge 406, which is
located opposite the first end wall 112, supports the charcoal
filter 124. Together, the charcoal filter support ridge 406, the
first side wall 118, the central wall 404 and a HEPA filter support
ridge 410 define a HEPA filter cavity 412 in which the HEPA filter
126 is slidably positioned. For periodic replacement, the HEPA
filter 126 can be slidably removed from the HEPA filter cavity
412.
[0027] Below the HEPA filter 126, the heat recovery core 128 is
supported by four core support walls 414, 416, 418 and 420. Each of
the core support walls 414, 416, 418 and 420 has angled bracket
members 421 that support the corners of the heat recovery core 128.
The upper core support wall 414, along with the lateral upstream
core support wall 416 and the outer shell 104 define a filtered air
cavity 422 between the HEPA filter cavity 412 and the heat recovery
core 128. The lateral upstream core support wall 416, the outer
shell 104, the lower core support wall 420 and a drip pan support
wall 424 all define a stale air inlet cavity 426 in which stale air
from the stale air chase 202 is introduced. The upper core support
wall 414, the lateral downstream core support wall 418, the central
wall 404, the outer shell wall 104, a blower fan support ridge 428,
define a stale air, blower fan exhaust cavity 430 in which the
stale air blower fan 148 is secured. The outer shell wall 104,
central wall 404, and the blower fan support ridge 428 define a
stale air exhaust port cavity 432. Stale air from the exhaust port
cavity 432 is exhausted out the stale air exhaust port 206.
[0028] Downstream from the heat recovery core 128, the drip pan
support wall 424 defines a UV light support passageway 434 in which
the UV light 138 is secured. The outer wall 104 along with the
lateral, downstream core support wall 418, and the lower core
support wall 420 define an evaporator cavity 436 in which the
evaporator 134 is located. The evaporator 134 can be secured either
to the heat recovery core 128 directly or to the angled brackets
421 of the support walls 418, 420. Below the condenser 140, a
condenser support ridge 438 supports the condenser 140 while
allowing air to pass therethrough. Near the lower end 111 of the
housing 102, the unit 100 has a lower central wall 440 with a bowed
portion 442 that accommodates the condenser 140. The bowed portion
442 of the lower central wall 440 along with the condenser support
ridge 438 define a condenser cavity 444. Below the condenser cavity
444, the lower central wall 440 along with the outer wall 104
define a blower cavity 446 in which the tempered air blower 146 is
secured. The blower cavity 446 communicates with the tempered air
chase 204 through the tempered-air port 205. At lower end portion
111 of the housing 102 and adjacent the blower cavity 446, the drip
pan support wall 424, the lower central wall 440 and the outer
shell 104 define a compressor/electrical panel cavity 448. The
compressor 142 along with the electrical panel 150 are housed
within the compressor/electrical panel cavity 448 so as to be
isolated from the various air flow paths.
[0029] The operation of the unit 100 will now be described with
reference to FIGS. 1 and 2. Generally, during operation, the unit
100 both cleans and dehumidifies the air supplied to a home. As
illustrated, the fresh air flows along fresh air flow path F,
recirculation air flows along a recirculation flow path R and the
stale air flows along stale air flow path S. The fresh air flow
path F and/or the recirculated air flow path R can form a supply
air flow path T through the unit 100. For example, when the unit
100 is operating in a fresh air mode or when a bathroom exhaust fan
is activated, the damper 120 will shift to block the recirculation
air passageway 116. This fresh air mode is used any time that a lot
of fresh air is required in a home, for instance, during vacuuming,
dusting, cooking, or removal of cigarette smoke. As shown by the
supply air flow path T, the fresh air flows through the activated
charcoal filter 124 to remove carbon based chemicals (VOCs) in
order to help reduce odors. The fresh air then passes through the
HEPA filter 126 in order to remove particulates down to 0.3 microns
in size. The HEPA filter 126 blocks pollens, molds and other types
of contaminants from entering the home through the unit 100. The
filtering by the HEPA filter 126 also helps to keep the downstream
components of the unit 100 relatively clean. The filtered fresh air
from the HEPA filter 126 then flows through the heat recovery core
128. In one example, the heat recovery core 128 is a matrix of
aluminum plates that allow energy from the stale air to pass to the
fresh air. This minimizes energy consumption while maximizing
efficiency. Stale air, for example from a bathroom exhaust fan, is
supplied to the unit 100 through stale air chase 202. The stale air
is exhausted from the stale air exhaust port 206 to a duct that
eventually exhausts the stale air to the outside. The amount of
stale air exhausted is in proportion to the amount of fresh air
supplied to the system such that neutral pressure is created in the
house. By having neutral pressure in the home, drafts and outside
infiltration is reduced. When a house has negative pressure,
outdoor pollutants are drawn through chimneys, flues and cracks in
the walls.
[0030] After passing through the heat recovery core 128, the fresh
air then flows through the evaporator 134. In one form, the unit
operates the evaporator 134 when the incoming air is above 50%
relative humidity. The evaporator coil 134 cools the air in order
to reduce the air's humidity. The moisture collected runs down the
evaporator 134, into the drip pan 136 and eventually out the drain
137. The cooled air then is irradiated with UV light from the UV
light 138 to destroy any type of organism in the air. After the air
is irradiated by the UV light 138, the air then passes through
condenser 140, which reintroduces the heat removed by the
evaporator 134. The now tempered air flow is blown by tempered air
blower 146 into the tempered air chase 204. Ductwork is attached to
the tempered air chase in order to distribute the tempered air
throughout the home. The tempered air chase 204, which runs the
entire length of the unit 100, allows for multi-positional
installation of ductwork.
[0031] In a recirculation air mode, the baffle 120 is positioned to
block the fresh air passageway 114. This allows the recirculation
air to flow from the recirculation air passageway 116 along flow
path R through the unit 100. As can be seen, with the exception of
flowing through the recirculation air passageway 116, the
recirculated air flows along the same components that was described
above with reference to the fresh air. This allows the filtering,
dehumidifying, and sanitizing of indoor air on a continual
recycling basis. In this mode, the exhaust blower 148 is normally
turned off. The exhaust blower 148 can be turned on when a bathroom
fan or some other type of exhaust fan is turned on inside the
house.
[0032] An air treatment system 800 according to one embodiment of
the present invention is illustrated in FIG. 8. In the illustrated
embodiment, the system 800 includes the unit 100, a forced air
furnace 802, and a controller 804 that is configured to sense air
temperature and humidity conditions so as to control the furnace
802 along with the unit 100. As can be seen, housing the components
of the unit 100 in a single, compact housing 102 makes installation
easier by reducing the amount of required ductwork. In the
illustrated embodiment, the forced air furnace 802 has a blower fan
that runs continuously so as to recirculate air throughout the
home. Fresh air supply duct 806 supplies air from outside the home
to the unit 100 and is attached to the fresh-air port 114 of the
unit 100. Return air duct 808 supplies return air to both the
forced air furnace 802 and the air treatment unit 100. A
recirculation air duct 810 offshoots from the return air duct 808
and is coupled to the unit 100 through recirculation air passageway
116. Stale air duct 812 supplies stale air, such as bathroom
exhaust air, kitchen exhaust air and the like, to the stale air
chase 202. As described above, the stale air chase 202 extends the
entire length of the unit 100 such that the stale air duct 812 can
be coupled at any position along the length of the unit 100.
Exhaust duct 814 exhausts stale air from the unit 100 to the
outside. Tempered air duct 816 resupplies tempered air to the
return duct 808 which in turn is supplied to the forced air furnace
802. Supply duct 818 supplies treated air from the furnace 802 to
the home. Alternatively or additionally, the system 800 can include
other types of air temperature control devices besides the furnace
802, such as air conditioning systems and heat pumps, to name a
few. In the system 800, the unit 100 operates in a similar fashion
as described above.
[0033] In another embodiment, as illustrated in FIG. 8, the
controller 804 can be operatively coupled to pressure sensor 820 in
order to monitor pressure inside the house. In one form, pressure
sensor 820 includes a diaphragm type sensor. In an emergency
negative pressure operational mode, the pressure sensor 820 senses
negative air pressure within the house, and in response, the
controller 804 activates the fresh air blower 146 in order to
equalize the air pressure in the house. Some sources of negative
air pressure in the house can be caused by exhaust fans for
industrial grade ovens and fireplaces. For instance, the emergency
negative pressure mode can be activated when a back draft is formed
in a chimney by the homeowner trying to light a fire in the
fireplace.
[0034] An air treatment system 900 according to another embodiment
of the present invention is illustrated in FIG. 9. Like the system
800 described above, system 900 includes the air treatment unit
100, a forced air furnace 802a and the controller 804. In the
illustrated embodiment, the blower furnace 802a only blows air
during heating or cooling, and when not operating, the furnace 802a
does not blow any air through the home. Like the previous
embodiment, the fresh air duct 806 supplies fresh air from outside
the home to the unit 100 through the recirculation passageway 100.
Recirculation duct 810a supplies air recirculated from the house to
the unit 100. In the same manner as described above, the stale air
duct 812 supplies stale air to the unit 100. Stale air is exhausted
from the unit 100 through stale air exhaust duct 814, which
exhausts the stale air outside the home. As shown, the tempered air
duct 816a is not coupled to the return air duct 808a. Rather, the
tempered air duct 816a is coupled to the supply duct 818a. This
allows the unit 100 to be constantly running to supply fresh air,
even when the forced air furnace 802a is not operating.
[0035] While the invention has been illustrated and described in
detail in the drawings and foregoing description, the same is to be
considered as illustrative and not restrictive in character, it
being understood that only the preferred embodiment has been shown
and described and that all changes and modifications that come
within the spirit of the invention are desired to be protected.
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