Note: Descriptions are shown in the official language in which they were submitted.
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AN AIR BLOWER VALIDATOR, AN HVAC SYSTEM AND
A METHOD OF MANUFACTURING AN HVAC SYSTEM
TECHNICAL FIELD
This application is directed, in general, to heating,
ventilating and air conditioning (HVAC) systems, and more
specifically, to air blower fans of HVAC systems.
BACKGROUND
In an HVAC system, an air blower is used to circulate
air through an enclosure and the HVAC system. Typically, the
air blower is used to pull air from the enclosure into the
HVAC system through ducts and push the air back into the
enclosure through additional ducts after conditioning the air
(e.g., heating or cooling the air). To
insure that the air
blower is working properly, a system controller (e.g., a
processor) is often used to monitor the operation of the air
blower. One way of monitoring the air blower is by using an
electrical switch to confirm if the motor is operating or not
operating.
Additionally, a pressure sensor may be used to
determine if air is being moved by the air blower.
SUMMARY
Certain exemplary embodiments can provide an air blower
validator, comprising: an air pressure detector including a
first pressure port configured to receive air from inside an
air blower housing of an HVAC system; and an air collector
configured to deliver said air to said first pressure port,
said air collector including a single pressure tap configured
to couple to an opening in said air blower housing.
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Certain exemplary embodiments can provide a method of
manufacturing an HVAC system including an air blower
validator having an air pressure detector and an air
collector, comprising: positioning a single pressure tap of
said air collector at a location of a housing of an air
blower to capture air pressure in said air blower housing;
and coupling said pressure tap to an opening at said
location, wherein said pressure tap is coupled to a first
pressure port of said air pressure detector.
Certain exemplary embodiments can provide an HVAC
system, comprising: an air blower having an air blower
housing and configured to circulate air through the HVAC
system; and an air blower validator coupled to the HVAC
system, including: an air pressure detector including a first
pressure port configured to receive said air from inside said
air blower housing; and an air collector configured to
deliver said air to said first pressure port, said air
collector including a single pressure tap configured to
couple to an opening in said air blower housing.
BRIEF DESCRIPTION OF THE DRAWINGS
Reference is now made to the following descriptions
taken in conjunction with the accompanying drawings, in
which:
FIG. 1A illustrates a block diagram of an embodiment of
an HVAC system constructed according to the principles of the
disclosure;
FIG. 1B illustrates a diagram of an air blower with an
embodiment of an air blower validator constructed according
to the principles of the present disclosure;
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FIG. 2 illustrates a block diagram of one embodiment
of an air blower validator constructed according to the
principles of the disclosure; and
FIG. 3 illustrates a flow diagram of an embodiment
of a method of manufacturing a HVAC system carried out
according to the principles of the disclosure.
DETAILED DESCRIPTION
Employing pressure sensors to monitor the operation
of an air blower can be expensive due to the sensitivity
needed to measure the changes of air pressure. This can
be especially true when variable speed motors are
employed due to the small changes in air pressure between
the various speeds.
Typically, a more sensitive (and
often more expensive) pressure sensor may be needed to
detect air pressure changes at these low flow conditions.
Thus, improvements in determining if an air blower is
operating properly, i.e., moving air, can be
advantageous.
This disclosure provides a proving device for an air
blower that is connected to the housing of an air blower.
The proving device, an air blower validator, includes an
air collector coupled to a supply port or supply ports of
an air pressure detector and configured to deliver air
from within the housing of the air blower to the supply
port or ports to allow detection of static pressure,
total pressure or velocity pressure from the air blower.
The air collector may include multiple sections. For
example, the air collector may include a pressure tap and
a supply conduit that couples the pressure tap to the
supply port of the air pressure detector. The
pressure
tap may be coupled to an opening of the air blower
housing and may extend through the air blower housing
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opening with an opening that faces air flow generated by
the air blower. The supply conduit delivers air captured
by the pressure tap to the supply port. The
supply
conduit may be external to the air blower housing. In
some embodiments, the air collector may include a single
section, the pressure tap. In these
embodiments, the
pressure tap may have one end that is coupled to the
supply port and an angled-end that extends into the air
blower housing and configured to capture total pressure,
including velocity pressure, from the air blower housing.
The air collector may include multiple pressure taps and
supply conduits.
The pressure tap of the air collector may be
positioned to capture a maximum total pressure or at
least substantially the maximum total air pressure
reading in the air blower housing. The mounting location
for capturing maximum total air pressure may be
determined by experimentation or theoretical calculation.
(See, for example, "FANS," by Theodore Baumeister, Jr.,
Mcgraw Hill Book Company Inc., 1935, pages 100-110). The
location may vary for different air blower models. In
some embodiments, utilizing radially or axially expanding
blower designs, the location may be between 180-230
degrees from the cut-off section of the air blower.
By locating the pressure tap as disclosed in one of
the embodiments herein, the air pressure detector may
capture the added benefit of velocity pressure (e.g.,
0.3" water column (wc) or higher) that makes a total
pressure reading reasonably above the operating settings
of the air pressure detector. Thus, the
air blower
validator can be used repeatedly and reliably to monitor
the operation of an air blower. This is
especially
useful for variable speed blowers operating at low flow
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conditions when changes in the total air pressure are
difficult to detect.
FIG. 1A is a schematic diagram of an embodiment of
an HVAC system 100 constructed according to the
principles of the present invention. The HVAC system 100
includes a return duct 110, a return plenum 115, an air
blower 120, a supply plenum 130, a supply duct 140, a
controller 150 and an air blower validator 160. One
skilled in the art will understand that HVAC system 100
may include additional components and devices that are
not presently illustrated or discussed but are typically
included in an HVAC system, such as, cooling coils and
heating elements. A
thermostat (not shown) is also
typically employed with a HVAC system 100 and used as a
user interface.
The air blower 120 is configured to circulate air
through an enclosure (not shown) by suctioning air from
the enclosure through the return duct 110 and the return
plenum 115, as indicated by arrow 112, and discharging
air to the enclosure, as indicated by arrow 132 through
the supply plenum 130 and the supply duct 140. The
supply plenum 130 is in fluid communication with the
supply duct 140 to supply discharged air to the
enclosure. The air
blower 120 may be a conventional
blower used in HVAC systems to circulate air through an
enclosure. In some
embodiments, the air blower 120 may
include a variable speed motor and operate at various
speeds. The air
blower 120 has a housing 122 that
includes, for example, a blower motor and wheel (not
illustrated).
Operation of the air blower 120 may be controlled by
the controller 150 based on inputs from, for example a
thermostat. The controller 150 may be a processor, such
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as a microprocessor, configured to direct the operation
of the HVAC system 100. As
illustrated in FIG. 1, the
controller 150 may be coupled to the air blower validator
160 through a wired-connection. A cable may be used to
couple the controller 150 to the air blower validator 160
through contacts (not shown) thereon. The cable and
contacts may be conventional components typically used in
a HVAC system. In some
embodiments, a wireless
connection may also be employed to couple the air blower
validator 160 to the controller 150.
The air blower validator 160 is configured to prove
the operation of the air blower 120. In other words, the
air blower validator 160 is configured to verify that the
air blower 120 is moving air. The air blower validator
160 includes an air pressure detector 162 and an air
collector 164. The air
pressure detector 162 is
configured to indicate if the air blower 120 is operating
properly based on air pressure (static, velocity or total
air pressure which is velocity pressure + static
pressure) associated with the air blower 120. The air
pressure detector 162 includes a first pressure port
configured to receive air from inside the air blower
housing 122. In one
embodiment, the air pressure
detector 162 is a pressure switch and includes a second
pressure port that receives air external from the air
blower housing 122. In such
an embodiment, the air
pressure detector 162 compares the pressures associated
with the air received from the two different locations
and operates a switch based thereon. In
another
embodiment, the air pressure detector 162 may be a
pressure transducer that converts the total pressure of
the air received from the air blower housing 122 into an
electrical signal. The
electrical signal may then be
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delivered to the controller 150 to verify operation of
the air blower 120. The pressure switch and the pressure
transducer may be conventional devices. The air pressure
detector 162 is connected to the air blower housing 122
and coupled to the pressure tap 166 of the air collector
164. The
pressure tap 166 is coupled to the first
pressure port and is positioned for the suspended opening
to face the air flow direction of the air blower 120.
The air collector 164 is configured to extend into
the air blower housing 122 and deliver air thereof to the
first pressure port. The air
collector 164 includes a
pressure tap 166 configured to suspend in the air blower
housing with an opening that faces air flow generated by
the air blower. The
pressure tap 166 may be an angled
device as illustrated having an opening that faces the
air flow generated by the air blower. The pressure tap
166, therefore, includes an end coupled to a pressure
port of the air pressure detector and an uncoupled end
that is suspended in the air blower housing 122 and faces
the air flow direction during normal operation. As
illustrated in FIG. 1B, an air collector may include a
supply conduit that couples a pressure tap to the supply
port of an air pressure detector.
FIG. 1B illustrates a diagram of an embodiment of an
air blower validator 170 constructed according to the
principles of the present disclosure. The air
blower
validator 170 is connected to an air blower housing 180.
The air blower validator 170 includes an air pressure
detector 172 and an air collector 174. The air pressure
detector 172 may be an air pressure switch or an air
pressure transducer as described above with respect to
the air pressure detector 162 of FIG. 1A. Coupled to a
pressure port of the air pressure detector 172 is the air
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collector 174. The air
collector 174 includes a supply
conduit 176 and a pressure tap 178. The pressure tap 178
is directly coupled to the air blower housing 180 and
positioned to capture air pressure therein. The pressure
tap 178 may be mounted directly to an opening of the air
blower housing 180. The pressure tap 178, therefore, may
be used to obtain static pressure from inside the air
blower housing 180. In one embodiment, the pressure tap
178 may extend perpendicularly or at least substantially
perpendicularly into the air blower housing 180 with
respect thereto and be used to obtain total pressure from
within the air blower housing 180. In one
embodiment,
the pressure tap 178 may extend between about 0.5 inches
to about 0.75 inches into the air blower housing.
The pressure tap 178 may include a portion that is
external to the air blower housing 180 and a portion that
extends into the air blower housing 180. As illustrated,
the supply conduit 176 may be external to the air blower
housing 180. The
length of the supply conduit 176 may
vary allowing the air pressure detector 172 to be mounted
in different locations. In some embodiments, the supply
conduit 176 may be rubber tubing that is typically used
to provide air from different locations to pressure
sensors in HVAC systems.
In some embodiments, such as illustrated in FIG. 2,
an air collector may include a pressure tap having a
first end configured to couple to a first pressure port
of an air blower detector and a second end that is
uncoupled and configured to extend into the air blower
housing 122 to capture the air. The second
end may
include an opening that is positioned to face an air flow
direction generated by the air blower during normal
operation.
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FIG. 2 illustrates a diagram of an embodiment of an
air blower validator 200 constructed according to the
principles of the disclosure. The air
blower validator
200 includes an air pressure detector 210 and an air
collector 220. The air pressure detector 210 includes a
first pressure port 212, a second pressure port 214
(represented by embodiments 214a and 214b), electrical
contact(s) 216 and a base 218 that is used to mount the
air pressure detector 210 to, for example, part of an air
blower. Screws,
such as sheet metal screws, or other
mechanical fasteners may be used to couple the air
pressure detector 210 to part of an HVAC system such as
the air blower housing.
Alternatively, an adhesive or
another means for coupling may be used to connect the air
pressure detector 210.
The first pressure port 212 extends from the air
pressure detector 210 wherein the second pressure port
214a is recessed.
Alternatively, the second pressure
port may also extend from the air pressure detector 210
as represented by 214b. The air collector 220 includes a
pressure tap 225 that is sized to fit over the extended
first pressure port 212 and may be coupled to the first
pressure port 212 via friction. In other
embodiments,
the pressure tap 225 may be coupled to the pressure port
212 via another means, such as an adhesive.
The pressure tap 225 may be constructed from rubber
tubing that is typically used to provide air from
different locations to pressure sensors in HVAC systems.
In other embodiments, the pressure tap 225 may be
constructed of another material, such as, plastic. One
skilled in the art will understand that the pressure tap
225 may be constructed of various materials that allow
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the pressure tap 225 to be suspended in an air blower
housing with an uncoupled end.
As illustrated, the pressure tap 225 has an angled-
opening that is positioned to face the air flow generated
by an air blower. The angled-
opening is shaped to
capture the total pressure in an air blower housing
wherein the total pressure equals the static pressure and
the velocity pressure. In one embodiment as illustrated,
the angle of the angled-opening may be about 30 to 60
degrees with respect to longest side of the pressure tap
225.
The air collector 220 may also be coupled between
the second pressure port 214b and an opening of the air
blower housing 218. The air collector 220 may be coupled
to a nipple 219 of the air blower housing 218. Through
this embodiment, the air blower validator 200 can obtain
the velocity pressure via the difference of static
pressure and total pressure provided to second pressure
port 214b and first pressure port 212, respectively.
FIG. 3 illustrates a flow diagram of an embodiment
of a method of manufacturing an HVAC system carried out
according to the principles of the disclosure. The HVAC
system may be a commercial system that includes, for
example, a rooftop unit. Alternatively, the HVAC system
may be a residential system. Some of the
steps of the
method 300 may occur during manufacturing of the HVAC
system.
Additionally, some of the steps of the method
300 may occur during installation of the HVAC system.
The method 300 begins in a step 305.
In a step 310, a pressure tap of an air collector is
positioned at a location of a housing of an air blower of
the HVAC system to capture air pressure in the air blower
housing. The
pressure tap may be used to collect total
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pressure or static pressure from inside the air blower
housing. The air
collector is part of an air blower
validator that also includes an air pressure detector.
In one embodiment, the air pressure detector may be, for
example, a pressure switch. In another
embodiment, the
air pressure detector may be a pressure transducer. The
location is determined to capture the maximum or at least
substantially the maximum velocity pressure from the air
blower. In one
embodiment, the location may be within
180 to 230 degrees from the cut-off section of the air
blower.
In a step 320, the pressure tap is connected to a
pressure port of the air pressure detector. In one
embodiment, the pressure tap may be connected via a
supply conduit. In another embodiment, the pressure tap
may be coupled directly to the pressure port. In one
embodiment, an air collector including the pressure tap
may be formed as an extension of the pressure port during
manufacturing of the air pressure detector. In
another
embodiment, the air collector may be coupled to the
pressure port after manufacturing of the air pressure
detector. The air pressure detector may include multiple
pressure ports and more than one of the pressure ports
may be coupled to the air collector to receive air from
inside the air blower housing.
At least a portion of the pressure tap is inserted
inside the air blower housing in a step 330. A portion
of the pressure tap may be inserted through an opening
that was pre-cut before installation. In some
embodiments, the opening may be cut during installation.
A portion of the pressure tap may be inserted about 0.5
inches to about 0.75 inches into the air blower housing.
The portion of the pressure tap inserted into the air
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blower housing suspends from the air blower housing and
remains uncoupled.
In a step 340, the portion of the pressure tap
inserted in the air blower housing is positioned to face
an air flow direction generated by the air blower. The
inserted portion of the pressure tap may have an angled-
opening that is positioned to face the air flow. In some
embodiments, the pressure tap itself may be angled with
an opening that can be positioned to face the air flow
direction. For
example, the pressure tap may be angled
at or about 90 degrees wherein a first end is connected
to the pressure port and a second end is positioned to
face the air flow direction and capture air. The
pressure tap is positioned to capture both velocity
pressure and static pressure for the air collector.
The air pressure detector is then connected to the
HVAC system in a step 350. In one
embodiment, the air
pressure detector is connected to the air blower housing.
The air pressure detector may be connected via a
mechanical connection such as by using screws. The
method 300 then ends in a step 360.
Those skilled in the art to which this application
relates will appreciate that other and further additions,
deletions, substitutions and modifications may be made to
the described embodiments.
