LIMITED LOSS LAMINAR FLOW DAMPERS FOR HEATING, VENTILATION, AND AIR CONDITIONING (HVAC) SYSTEMS
HVAC devices, systems, and methods include dampers for controlling the flow of air or other gasses through an HVAC duct, often while inhibiting turbulence within the duct or pressure loss within the duct. Embodiments of such dampers may employ a two-part damper arrangement. In many embodiments, flow will travel through the middle of the damper uniformly and with a laminar flow. One or more small, relatively unobtrusive sensor (optionally being wireless) can be included for controlling operation of the damper, the sensor(s) optionally measuring the distance between damper elements, sound, air flow, or the like, with such sensor(s)/damper combination inhibiting inadvertent pressure drop and turbulence in flows through the damper. The damper elements may optionally comprise airfoil cross-sections, with alternative dampers having a resilient helical configuration that can choke down flow by inducing a vortex in the flow, allowing static pressure regain to occur within the duct system.
This application claims the benefit of priority from U.S. Provisional Patent Application No. 60/756,037 filed Jan. 3, 2006 (Attorney Docket No. 025920-000500US). This application is related to U.S. patent application Ser. No. 11/429,418 filed May 5, 2006 (Attorney Docket No. 025920-000120US), which claims the benefit of U.S. Patent Application No. 60/678,695 filed May 6, 2005 (Attorney Docket No. 025920-000100US) and U.S. Patent Application No. 60/755,976 filed Jan. 3, 2006 (Attorney Docket No. 025920-00011US); and to U.S. patent application Ser. No. 11/180,310 filed Jul. 12, 2005 (Attorney Docket No. 025920-000210US), which is a continuation of U.S. Pat. No. 6,951,324 (Attorney Docket No. 025920-000200US); and to U.S. patent application Ser. No. 10/857,211 filed May 24, 2004 (Attorney Docket No. 025920-000300US); and to U.S. patent application Ser. No. 10/860,573 filed Jun. 2, 2004 (Attorney Docket No. 025920-000400US). This application is also related to U.S. Patent Publication No. 2003/0171092. The entire contents of each of these applications and their priority filings is incorporated herein by reference for all purposes.
BACKGROUND OF THE INVENTIONThe present disclosure relates to methods, systems and apparatuses for heating, ventilation, and air conditioning (“HVAC”) systems and, more particularly to limited loss and/or laminar flow dampers for such systems.
In general, HVAC systems control the temperature and humidity of indoor air. In most HVAC systems, air is drawn in, filtered, cooled and dehumidified or heated and humidified, and then delivered to an air conditioned space. The greatest portion of incoming air is drawn from the air conditioned space for recirculation through the HVAC system. HVAC system includes fans and ductwork for moving conditioned air to where it is needed while passing it through cooling and/or a heating sections of the ductwork.
One risk which must be addressed in designing and operating HVAC systems is that of biological contamination by bacteria, molds, and viruses. In recent years, biological problems in indoor environments have received considerable attention. Most frequently, molds, bacteria and/or virus grow wherever water collects in a HVAC systems ductwork, such as at its cooling sections.
Poor indoor air quality (“IAQ”) and the spread of infectious disease through a HVAC system, at a minimum, can reduce worker productivity and increase absenteeism. Even more alarming is the potential liability for illnesses suffered by workers due to poor IAQ. The Legionnaires' disease outbreak in Philadelphia in 1976, is probably the most publicized instance of illness caused by poor IAQ. Even if contamination by molds and bacteria doesn't affect workers, their growth within HVAC system equipment creates maintenance problems which are very costly to correct. Left uncorrected, these problems exacerbate and, at a minimum, eventually reduce system's heat transfer efficiency.
HVAC systems in residential, commercial, education and research buildings usually include metallic pipes, hollow composite materials such as tubes, and the like. The systems are typically supported from and between floor or ceiling joists. The HVAC system typically includes a primary or main duct. A series of smaller branch ducts which extend from the main duct are mounted between adjacent floor or ceiling joists. Such main and branch ducts are normally supported by metal hangers located between the joists. Often the branch ducts include pipes and conduit lines for transporting liquid or gas which are suspended from ceiling joists or an adjacent wall typically with Unistrut®, threaded rod, couplings, and various hanger brackets.
Piping and conduits that supply gas and/or liquids within buildings require careful preparation. Builders or contractors typically use ladders or scaffolding to reach areas where piping is routed so installation may be cumbersome. Occasionally the pipe or conduits are prepared on the ground and installed by ladder as more complete assemblies. Pipe and conduit assemblies prepared on the ground or a floor of a building under construction are more unwieldy than the unassembled components, but pre-assembly is often more practical. Furthermore, conditions existing at construction sites and the number of differing types of components used in assembling a HVAC system render cataloging those components impractical if not impossible.
Generically, a terminal unit, also sometimes referred to as an air handling unit, is a HVAC system component that is located near an air conditioned space that regulates the temperature and/or volume of air supplied to the space. When providing air to a more critical environment such as a laboratory, an almost identical ductwork section is frequently referred to as a lab valve damper rather than as a terminal unit. One difference between a terminal unit and a lab valve damper is the precision with which the unit controls the temperature and humidity of conditioned air. As used throughout this document, the phrase terminal unit may identify either a terminal unit or a lab valve damper.
A HVAC system may be assembled using any one of several different types of terminal units. Generally, the mechanical portion of a terminal unit includes a casing through which air flows during operation of a HVAC system. Accordingly, a casing includes an inlet for receiving air from ductwork of a HVAC system, and an outlet for supplying air to a space in a building. Casings are usually fabricated from 22 gauge galvanized sheet steel. Due to the use of such light material, casings are easily damaged during shipping to a building site and during installation into the HVAC system. Those familiar with such damage to terminal unit casings frequently refer to it as “oil canning” because it resembles how a light gauge oil can collapses as the liquid flows out.
In a typical hydronic (all-water) HVAC system, the mechanical portion of a terminal unit includes a heat exchanging coil. Heated and/or cooled water is pumped from a central plant through pipes to the coil. Air from the HVAC system's ductwork passes through the coil after entering and before leaving the casing. Usually, a single terminal unit is dedicated for heating and/or cooling each air conditioned space. Air from the duct connected to the terminal unit passes through the coil to be heated and/or cooled by water flowing through the coil before the air enters the air conditioned space.
A Variable Air Volume (“VAV”) HVAC system, in response to a control signal from a thermostat or room sensor, supplies only that volume of hot and/or cold air to an air conditioned space needed to satisfy the space's thermal load. A VAV HVAC system meets changing cooling and/or heating requirements by adjusting the amount, rather than the temperature, of air that flows to a space. For most buildings, a VAV HVAC system yields the best combination of comfort, first cost, and life cycle cost.
A VAV terminal unit is a relatively complex assembly which includes sheet metal, plumbing, electrical and pneumatic components. For example, a VAV terminal unit includes an airflow sensor that senses the velocity of air entering the terminal unit. To adjust the volume of cold air, a VAV terminal unit frequently includes a damper which automatically opens and closes as needed.
As a space's thermal load decreases, the damper starts closing thereby reducing the amount of heated or cooled air supplied to the space. Alternatively, the volume of air entering a space may be controlled by varying the speed of a fan included in the terminal unit. For either type of VAV terminal unit, VAV HVAC systems save energy consumed by fans in comparison with alternative HVAC systems by continually adjusting airflow to the heating and/or cooling required.
To be operable and fully-functional, terminal units for a hydronic HVAC system often include a coil, ductwork for supplying air to the coil and receiving air from the coil, plumbing for supplying water into and receiving water from the coil, and a control valve for regulating the amount of water flowing through the coil.
To match the flow of air through the terminal unit's ductwork to the profile of the coil, the terminal unit's ductwork may include transition sections both for air entering the coil and for air leaving the coil. In addition, a terminal unit may also include a re-heat coil, and/or a sound attenuator. In a terminal unit adapted for use in a VAV HVAC system, the terminal unit's ductwork may also include a damper and a damper actuator or variable speed fan for controlling the volume of air supplied by the terminal unit, and an airflow sensor for sensing the volume of air passing through the terminal unit.
Usually, all of the various parts needed to assemble a fully-functional VAV HVAC system's terminal unit arrive at building construction sites as separate components. Generally, these components are then assembled into a fully functional terminal unit at the construction site. Due to cluttered working conditions usually existing at a construction site where workers skilled in different crafts, e.g. plumbing, electrical, structural, etc., must concurrently collaborate to complete the building project, assembling the various components into a fully functional terminal unit may occupy the better part of a day. Furthermore, present practices and equipment are poorly adapted for swiftly constructing a high quality HVAC system that is easily commissioned.
For example, because it is less expensive to wire a HVAC system's terminal units with 24 volt low voltage electrical power rather than 220 or 110 volt power, presently sections of buildings include transformer trees which an electrician generally assembles by installing multiple step down transformers on an electrical panel. This technique permits wiring 220 or 110 volt electrical power to the transformer tree on each panel, with the 24 volt low voltage electrical power then being wired individually from a transformer on the panel over distances of five (5) to one hundred (100) feet to a terminal units for energizing its Direct Digital Control (“DDC”) controller, and 2 way or 3 way automatic temperature control (“ATC”) control valve.
Usually, terminal units are supported from a building using angle brackets, straps, or thread rod. Usually these support devices are attached directly to the terminal unit. Terminal unit casings are usually made using 22 gauge sheet metal. Due to the use of this light material, casings are easily dented or bent during installation.
With current construction site labor costing up to $80.00/hour, assembling a terminal unit at a construction site may cost $500.00 to $1,000.00 for labor alone. Furthermore, terminal units assembled at a construction site generally differ from one another due to assembly by different craftsmen, and insufficient use of identical components in assembling each terminal unit. Due to conditions existing at construction sites and the number of differing types of components used in assembling a HVAC system, cataloging the components used in assembling the system is impractical. Lastly, construction sites generally lack any facilities for individually pre-testing building components, such as terminal units, assembled on-site.
After assembling a HVAC system, it must be activated, tested and commissioned to ensure IAQ. Testing a HVAC system only after it is completely assembled inevitably results in many hours of problem-solving and leak-hunting. Usually, there are leaky joints, broken valves, damaged pipes, leaky coils and improperly assembled components that must be tracked down which further increases building costs. After finding a faulty component, it must be identified, ordered and replaced which takes time and delays completion of the building project. Furthermore, years after a building project is complete to maintain IAQ a building manager responsible for the HVAC system's maintenance will surely have to identify and replace broken components.
The preceding considerations arising from construction site assembly of fully functional terminal units slows construction, increase building costs, requires rework when a terminal unit experiences an initial failure, and ultimately makes more difficult and expensive maintaining a building's HVAC system years after those responsible for its assembly are no longer available.
A variety of dampers are used in the HVAC industry. Many of these dampers, when installed in an HVAC system, have an associated air flow monitoring device to sense the pressure drop or otherwise measure the air moving across the damper, and to adjust the position of the damper so as to control airflow therethrough. The sensors are often located in the inlet or outlet of the damper. Unfortunately, many dampers and/or sensors induce turbulence, and in some cases rely on sensing pressures or the like at large numbers of locations distributed across the duct, increasing pressure drops, noise, and energy use.
In light of the above, it would generally be desirable to provide improved HVAC devices, systems, and methods. It would be particularly desirable to provide improved techniques and devices for controlling flow of air and other gasses within the ductwork of an HVAC system.
BRIEF SUMMARY OF THE INVENTIONImproved HVAC devices, systems, and/or methods include dampers for controlling the flow of air or other gasses through an HVAC duct, often while inhibiting turbulence within the duct and/or pressure loss within the duct at least when the damper is in an open flow configuration. By limiting flow turbulence, these embodiments may facilitate relatively simple flow measurement techniques, allowing sufficiently accurate flow measurements without, for example, having to resort to a multi-axis flow sensor. Embodiments of such dampers may employ a two-part damper arrangement. In many embodiments, flow will travel through the middle of the damper uniformly and with a laminar flow. One or more small, relatively unobtrusive sensors (optionally being wireless) can be included for controlling operation of the damper, the sensor(s) optionally measuring the distance between damper elements, sound, air flow, or the like, with such sensor(s)/damper combination inhibiting inadvertent pressure drop and turbulence in flows through the damper. The damper elements may optionally comprise airfoil cross-sections, with alternative dampers having a resilient helical configuration that can choke down flow by inducing a vortex in the flow, allowing static pressure regain to occur within the duct system. Such dampers may have control advantages, enhance energy efficiency, limit noise, and/or provide enhanced performance characteristics.
In a first aspect, embodiments of the present invention provide a damper assembly or system for use in a heating, ventilation, and air conditioning (HVAC) system. The damper assembly or system includes a casing having an inlet and an outflow with a flow direction extending therebetween, a first damper member movably disposed within the casing, and a second damper member movably disposed within the casing. The damper members each have a cross-sections and are movable between an open flow configuration and a restricted flow configuration such that laminar flow is maintained as the flow is restricted. The assembly may also include a damper assembly controller coupled to the damper members. In some cases, the assembly includes a flow sensor coupled to the damper members. Optionally, the flow sensor may measure pressure at less than 5 locations across the dampers. In some cases, the assembly includes a first sensor coupled with the first damper member. The first sensor can detect an orientation of the first damper member relative to the casing. In some cases, the first sensor is disposed at or near a trailing end of the first damper member. A first sensor may detect an orientation of the first damper member relative to the second damper member. The assembly may also include one or more air stops. In some aspects, the assembly includes a first damper member having a trailing end and a second damper member having a trailing end, and the first damper member trailing end and the second damper member trailing end are configured to be moved toward each other when the assembly is moved toward a restricted flow configuration.
In another aspect, embodiments of the present invention provide a damper assembly or system for use in a heating, ventilation, and air conditioning (HVAC) system. The damper assembly or system includes a casing having an inlet and an outflow with a flow direction extending therebetween, and a damper member disposed within the casing, the damper member comprising a helical body deformable between an open flow configuration and a restricted flow configuration. The damper in at least one configuration may have a shape suitable for inducing a vortex in a flow within the casing.
In yet another aspect, embodiments of the present invention provide a method of controlling a fluid flow in a heating, ventilation, and air conditioning (HVAC) system. The method includes flowing a fluid through a casing inlet toward a casing outlet, flowing the fluid across a plurality of damper members disposed within the casing, restricting an amount of the fluid passing through the casing by actuating a first damper member, and maintaining a laminar flow within the fluid during the actuation of the first damper member. The method may also include sensing an orientation of the first damper member. In some cases, the method includes sensing a pressure within the casing. The step of restricting the amount of fluid passing through the casing may include actuating a second damper member. Relatedly, the method may also include maintaining the laminar flow during actuation of the second damper member. Optionally, the method may include sensing an orientation of the second damper member. For example, the method may include sensing an orientation of the second damper member relative to the first damper member. In some cases, the method includes sensing an orientation of the second damper member relative to the casing. A cross section of the first damper member can include an aerodynamic profile and a cross section of the second damper member can include an aerodynamic profile. In some cases, the method includes sensing a distance between the first damper member and the second damper member.
These and other features, objects and advantages will be understood or apparent to those of ordinary skill in the art from the following detailed description of the preferred embodiment as illustrated in the various drawing figures.
BRIEF DESCRIPTION OF THE DRAWINGS
The perspective view of
For VAV zone-control units 100, the mechanical terminal unit 102 preferably includes a damper assembly, not visible in
To heat or cool air flowing through the mechanical terminal unit 102, the casing 104 includes a coil 122 that is located near the air inlet thereto, and which adapts the mechanical terminal unit 102 for inclusion in a hydronic HVAC system. The casing 104 includes both an inlet collar, not visible in
The mechanical terminal unit 102 is preferably selected from among various different types and styles sold by Krueger based in Richardson, Tex. Krueger is a division of Air Systems Components (ASC) which is part of the Dayton, Ohio Air System Components Division of Tomkins Industries, Inc. of London, England.
To fashion the mechanical terminal unit 102 into a zone-control unit 100 ready for installation into a building's HVAC system, various plumbing components must be added for circulating either hot or cold water through the coil 122. For supplying water to the coil 122 the zone-control unit 100 includes an inlet piping assembly 202. The piping assembly 202 includes an L-shaped section of pipe 204 which connects at one end to a lower header of the coil 122, not visible in
The zone-control unit 100 also includes an outlet piping assembly 232 for receiving water from the coil 122. A short length of pipe 234 which ends in a tee 236 connects to an header 238 of the coil 122. A manual air vent 242 is connected to and projects upward above the tee 236 to facilitate eliminating air from the piping assemblies 202, 232 following first assembling the HVAC system, or reassembly of the zone-control unit 100 when maintenance or repairs become necessary. An L-shaped section of pipe 244 is connected to and depends below the tee 236. Similar to the pipe 204, an end of the pipe 244 furthest from the tee 236 ends at a union 246. The other half of the union 246 connects to a 2 way or 3 way ATC control valve 252. The ATC control valve 252 may either be of a type depicted in
A side of the ATC control valve 252 furthest from the union 246 connects to a union 254. Connecting the ATC control valve 252 into the piping assembly 232 on both sides with unions 246, 254 facilitates its replacement when maintenance or repairs become necessary. A tailpiece 262, connected to the other side of the union 254 furthest from the ATC control valve 252, receives both a P/T port 264 and a manual air vent 266. The P/T ports 214 and 264 facilitate measuring pressure and/or temperature of water circulating through the coil 122. The vent 266 facilitates eliminating air from the piping assembly 232 following first assembling the HVAC system, or reassembly of the zone-control unit 100 when maintenance or repairs become necessary. A manual balancing valve 272 connects to the other side of the tailpiece 262 from the furthest from the union 254. An opposite side of the valve 272 from the tailpiece 262 receives a length of pipe 274 which, similar to the pipe 224, adapts the piping assembly 232 for connecting to a building's plumbing. The valves 222, 216, 272 and other plumbing fittings included in the piping assemblies 202, 232 are preferably manufactured by HCI of Madison Heights, Mich. The valves 222, 272 permit isolating from the building's plumbing, when maintenance or repairs become necessary, the coil 122 and those portions of the piping assemblies 202, 232 which connect to the valves 222, 272.
As described thus far, the zone-control unit 100 including the piping assemblies 202, 232 are substantially the same as those which a skilled sheet metal worker, controls contractor, electrician, and pipe fitter might collectively assemble at a building site. However, in assembling zone-control units 100 in accordance with the present invention for a particular building project or significant portion thereof, all of the lengths of pipe, plumbing fittings, valves, vents, P/T ports, etc. are the same. Consequently, when a repair become necessary a building manager or the manager's personnel responsible for maintaining the HVAC system may confidently order a replacement part knowing that it will surely fit because the plumbing of each zone-control unit 100 is not unique. Rather, in accordance with the present invention the plumbing of zone-control units 100 is uniform throughout the building or significant portion thereof. Furthermore, because plumbing of zone-control units 100 is uniform throughout the building or significant portion thereof, acting either from prudence or caution a building manager may confidently maintain an inventory of plumbing components for the zone-control units 100 to have on hand when they need repair thereby significantly reducing downtime while also maintaining IAQ.
In addition to being assembled with uniform plumbing, in accordance with the present invention tags 282 are attached to each valve 252, 272 or other component that are likely to eventually require replacement. After the HVAC system has been commissioned, when a failure occurs and is located, the presence of an identifying tag 282 attached to a failed component simplifies its replacement and reduces the time required therefor. The tags 282 are particularly helpful if components from different manufacturers and/or different catalogs have been incorporated into the HVAC system. The tags 282 are preferably engraved plastic, but may also be made from metal, paper, or any other appropriate material. The tags 282 may carry barcodes or plain language, for example, and may be customized to provide information in the manner most useful for a particular project. In accordance with the present invention, performance requirements for each zone-control unit 100 such as GPM, CFM, CV and so on are marked thereon in an accessible and well defined location.
Also in accordance with the present invention, each pipe 224, 274 is sealed by a spun copper cap 284 which is five (5) times thicker than the pipe 224, 274, and the assembled piping assemblies 202, 232 include a pressure gauge 286. Following fabrication and sealing of the piping assemblies 202, 232, they are pressure tested with, for example, a gas such as air. Other gasses or a liquid may be used as appropriate for materials used in the piping assemblies 202, 232. A typical pressure range used in testing assembled piping assemblies 202, 232 and coil 122 is 20-400 psi, and in one embodiment is preferably 140 psi. While pressurized, the piping assemblies 202, 232 and the coil 122 are checked for leaks, e.g. with a soap solution. Any defects in assembly found during pressure testing are repaired and/or defective components replaced. For example, experience in assembling zone-control units 100 in accordance with the present invention indicates that about 3 to 7% of new coils 122 are defective and must be replaced.
When inspection and pressure testing indicates that no leaks appear to exist in the piping assemblies 202, 232 and the coil 122, they are then sealed and re-pressurized to at least 100 psi, preferably 140 psi. After pressurization, the piping assemblies 202, 232 and the coil 122 remain sealed for 24 hours throughout which they must hold the pressurization to confirm that the zone-control unit 100 is undergoing installation into a HVAC system. After the piping assemblies 202, 232 and the coil 122 pass this 24 hour quality assurance test, zone-control units 100 can be ready for shipping to a construction site. In accordance with one embodiment of the present invention, the piping assemblies 202, 232 and coil 122 of zone-control units 100 ready for installation remain pressurized continuously after their 24 hour quality assurance test at a pressure of at least 60 psi until they are about to be installed into a building's HVAC system. In some cases, the shipping pressure can be 40 psi, or any other desired pressure.
Immediately before installing a zone-control unit 100 at a construction site, their readiness for installation can be confirmed by checking the pressure gauge 286. If the pressure gauge 286 fails to indicate a specified pressure, then the zone-control unit 100 may need further testing and/or repair, and should not be installed into the HVAC system. Instead an identically assembled zone-control unit 100 having a pressure gauge 286 which indicates the specified pressure may be immediately substituted for a defective one, and the defective zone-control unit 100 may either be repaired and re-tested at the construction site, or it may be returned to its vendor for repair.
Identifying and replacing faulty piping assemblies 202, 232 and/or coil 122 in this way prior to installing the zone-control unit 100 saves time and money. The present invention can eliminate an inability to test the piping assemblies 202, 232 and coil 122 of each zone-control unit 100 assembled at a construction site until the entire HVAC system is completely assembled and ready for commissioning. Off-site assembly and testing of zone-control units 100, rather than assembling the components at the construction site, improves quality control by individually assuring that each zone-control unit 100 is ready for installation in a HVAC system. In this way the present invention saves time and money that would otherwise be spent tracking down leaks that occur using traditional on-site assembly of zone-control units 100. Furthermore, by preventing pinhole leaks in the zone-control unit 100, which inevitably result in mold, biochemical hazards, etc., the present invention significantly improves IAQ both initially and throughout the HVAC system's service life.
One problem which arises with assembling zone-control units 100 at a location remote from a construction site is that during their transportation to the site and during installation into a building's ductwork zone-control units 100 may be manipulated by the piping assemblies 202, 232 and/or the coil 122 of the mechanical terminal unit 102. Such handling of zone-control units 100 during installation may damage seals between the components as well as the components themselves. Furthermore, such damage may not be noticed until the HVAC system is pressurized for commissioning or at a later date. At that time, locating a leak or malfunctioning part may be time-consuming, virtually impossible and cost prohibitive. To reduce any possibility that a zone-control unit 100 might be damaged while being transported from its assembly, test and qualification location to a construction site and to facilitate handling the zone-control unit 100 during its installation into the HVAC system, in accordance with the embodiment of the present invention illustrated in
Each of the handles 502 includes an L-shaped handle mounting bracket 504 which is rigidly secured to a wall 132 of the mechanical terminal unit 102 which is nearest to the piping assemblies 202, 232. As depicted in
For use with the zone-control unit 100, each plate 506a is also pierced by a rectangularly-shaped hole 512, and by a pair of circularly-shaped holes 514 illustrated with dashed lines in
Arranged in this way, the handle mounting brackets 504 and plates 506a provide a structure for mechanically coupling the mechanical terminal unit 102 and the piping assemblies 202, 232 together thereby reducing any possibility that the zone-control unit 100 might be damaged while being transported from its assembly, test and qualification location to a construction site. Furthermore, the handles 502 protect zone-control units 100 during shipping, and facilitate their handling during installation into the HVAC system such as maneuvering zone-control units 100 into position in a building's ductwork. During installation, the handle mounting brackets 504 and plates 506a maintain positional relation-ships between the mechanical terminal unit 102 including the coil 122 and the piping assemblies 202, 232 because the handle mounting brackets 504 and plates 506a mechanically bind the entire zone-control unit 100 together into a single unit.
DDC controllers include a communication capability that permits a central computer to monitor a building's HVAC system's operating status, and to coordinate operation of the various portions of the system including all of its terminal units. DDC controllers are equipped with Local Area Network (“LAN”) communications capability. To facilitate installing the zone-control unit the electrical components enclosure is optionally equipped with a 100 ft. length of LAN cable connected to the DDC controller Establishing the LAN that interconnects groups of zone-control units may involve the LAN cables of all but one of the zone-control units in the group be connected to another one of the group's zone-control units.
It is appreciated that inlet piping assembly second passage 1320 and outlet piping assembly second passage 1420 each can be sealed, inlet piping assembly first passage 1310 can be in sealed communication with thermal transfer assembly supply port 1210, and outlet piping assembly first passage 1410 can be in sealed communication with the thermal transfer assembly return port 1220. When sealed in this fashion, thermal transfer unit 1200 can contain a vacuum, a non-pressurized fluid, or a pressurized fluid. Inlet piping assembly second passage 1320 and outlet piping assembly second passage 1420 can be manufactured from, for example, ¾ inch type L copper water pipe. They can be sealed according to a heating and spinning procedure that introduces no annealing or distortion of the pipe. After zone-control unit 1000 is placed in the desired location relative to the HVAC system, distal tips of inlet piping assembly second passage 1320 and outlet piping assembly second passage 1420 can be cut, and connected with other HVAC piping or hose elements, such as a hot water piping building loop. Relatedly, zone-control unit 1000 includes a pressure gauge 1710 coupled with inlet piping assembly 1400. In some embodiments, pressure gauge 1710 may be coupled with thermal transfer unit 1200 or outlet piping assembly 1300. Inlet piping assembly 1300 may be coupled with a drain valve 1330, a Y-strainer 1340, a pressure/temperature port 1350, or a supply shutoff valve 1360, or any combination thereof. Outlet piping assembly 1400 may be coupled with control valve 1430, a balancing valve (not shown), a vent (not shown), a pressure/temperature port 1450, or a return shutoff valve 1460, or any combination thereof. Control valve 1430 may be an automatic temperature control (ATC) valve having a compensated ball valve including an integral pressure limiting and flow setting apparatus. Valve 1430 can assure consistent flow response regardless of the head pressure. In some cases, there is no CV setting on the valve. Relatedly, zone-control unit 1000 may include a field set manual or factory programmable maximum flow setting. In some embodiments, valve balancing may be accomplished in less than 30 seconds. Valve 1430 may have a shutoff pressure of 200 psi. Conveniently, valve 1430 may have a pressure sufficient to counteract a heating loop dead head pressure, which can be 50 psi or more. In related embodiments, valve 1430 can be a ½ inch, a ¾ inch, or 1 inch valve. Control valve 1430 may be a modulating Siemens ATC.
Thermal transfer unit 1200 may be coupled with a vent 1230 such as an air vent. In some instances, vent 1230 is a manual air vent disposed at or toward the highest point of thermal transfer unit 1200. Vent 1230 can help ensure proper drainage of air or other unwanted fluids or gasses that enter the system, which can have deleterious effects on an HVAC system. For example, unwanted air in a hot water system can cause cavitation in a hot water pump, which may cause malfunction or destruction of the pump or other system components. Vents can also help ensure optimum flow characteristics when draining thermal transfer unit 1200 or other zone-control unit 1000 components. Full drainage of such components can facilitate the removal of unwanted particles such as rust or other chemical buildup. In some embodiments, vent 1230 is constructed of a non-corrosive military grade brass. In the embodiment shown here, zone-control unit 1000 includes a duct interface 1110 which is coupleable with duct or casing 1100, which may be attached with or integral to a duct or ductwork of an HVAC system. Bracket 1500, which may include a handle, supports duct interface 1100, inlet piping assembly 1300, and outlet piping assembly 1400 with relative positions appropriate for use in an HVAC system or other climate control system. In some cases, bracket 1500 may be a handle configured to maintain duct or casing 1100, inlet piping assembly 1300, and outlet piping assembly 1400 in positional relationship.
As shown in
It is appreciated that inlet piping assembly second passage 2320 and outlet piping assembly second passage 2420 each can be sealed, inlet piping assembly first passage 2310 can be in sealed communication with thermal transfer assembly supply port 2210, and outlet piping assembly first passage 2410 can be in sealed communication with the thermal transfer assembly return port 2220. When sealed in this fashion, thermal transfer unit 2200 can contain a vacuum, a non-pressurized fluid, or a pressurized fluid. Relatedly, zone-control unit 2000 includes a pressure gauge 2710 coupled with inlet piping assembly 2400. In some embodiments, pressure gauge 2710 may be coupled with thermal transfer unit 2200 or inlet piping assembly 2300. Inlet piping assembly 2300 may be coupled with a drain valve 2330, a Y-strainer 2340, a pressure/temperature port 2350, or a supply shutoff valve 2360, or any combination thereof. Outlet piping assembly 2400 may be coupled with control valve 2430, a manual balancing valve 2470, a vent (not shown), a pressure/temperature port 2450 disposed upstream of control valve 2430, a pressure/temperature port 2452 disposed downstream of control valve 2430, or a return shutoff valve 2460, or any combination thereof. In some cases, balancing valve 2470 may be a Griswold pressure independent balancing valve. Thermal transfer unit 2200 may be coupled with a vent 2230 such as an air vent. In the embodiment shown here, zone-control unit 2000 includes a duct interface 2110 which is coupleable with duct or casing 2100, which may be attached with or integral to a duct or ductwork of an HVAC system. Bracket 2500, which may include a handle, supports duct interface 2110, inlet piping assembly 2300, and outlet piping assembly 2400 with relative positions appropriate for use in an HVAC system or other climate control system. In some cases, bracket 2500 may be a handle configured to maintain duct or casing 2100, inlet piping assembly 2300, and outlet piping assembly 2400 in positional relationship.
As shown in
It is appreciated that inlet piping assembly second passage 3320 and outlet piping assembly second passage 3420 each can be sealed, inlet piping assembly first passage 3310 can be in sealed communication with thermal transfer assembly supply port 3210, and outlet piping assembly first passage 3410 can be in sealed communication with the thermal transfer assembly return port 3220. Similarly, bypass piping assembly 3800 can be in sealed communication with inlet piping assembly 3300 and outlet piping assembly 3400 so as to provide a fluid passage therebetween, whereby the passage can be open and closed via operation of bypass shutoff valve 3810. When sealed in this fashion, thermal transfer unit 3200 can contain a vacuum, a non-pressurized fluid, or a pressurized fluid. Relatedly, zone-control unit 3000 includes a pressure gauge 3710 coupled with outlet piping assembly 3400. In some embodiments, pressure gauge 3710 may be coupled with thermal transfer unit 3200 or inlet piping assembly 3300. When bypass shutoff valve 3810 is in the open position, fluid can flow directly from inlet piping assembly 3300 to outlet piping assembly 3400 without flowing through thermal transfer unit 3200. When bypass shutoff valve 3810 is in the closed position, fluid can flow from inlet piping assembly 3300 to outlet piping assembly 3400 through thermal transfer unit 3200, without flowing through bypass piping assembly 3800. Inlet piping assembly 3300 may be coupled with a drain valve 3330, a Y-strainer 3340, a pressure/temperature port 3350, or a supply shutoff valve 3360, or any combination thereof. Outlet piping assembly 3400 may be coupled with control valve 3430, a manual balancing valve 3470, a vent (not shown), a pressure/temperature port 3450 disposed upstream of control valve 3430, a pressure/temperature port 3452 disposed downstream of control valve 3430, or a return shutoff valve 3460, or any combination thereof. Thermal transfer unit 3200 may be coupled with a vent 3230 such as an air vent. In the embodiment shown here, zone-control unit 3000 includes a duct interface 3110 which is coupleable with duct or casing 3100, which may be attached with or integral to a duct or ductwork of an HVAC system. Bracket 3500, which may include a handle, supports duct interface 3110, inlet piping assembly 3300, and outlet piping assembly 3400 with relative positions appropriate for use in an HVAC system or other climate control system. In some cases, bracket 3500 may be a handle configured to maintain duct or casing 3100, inlet piping assembly 3300, and outlet piping assembly 3400 in positional relationship.
As shown in
Proportional valves (including those having characteristics similar to those graphically illustrated in
The two-part damper design of
Although the present invention has been described in terms of the presently preferred embodiment, it is to be understood that such disclosure is purely illustrative and is not to be interpreted as limiting. Consequently, without departing from the spirit and scope of the invention, various alterations, modifications, and/or alternative applications of the invention will, no doubt, be suggested to those skilled in the art after having read the preceding disclosure. Accordingly, it is intended that the following claims be interpreted as encompassing all alterations, modifications, or alternative applications as fall within the true spirit and scope of the invention.
Claims
1. A damper assembly for use in a heating, ventilation, and air conditioning (HVAC) system, the assembly comprising:
- a casing having an inlet and an outflow with a flow direction extending therebetween;
- a first damper member movably disposed within the casing; and
- a second damper member movably disposed within the casing;
- the damper members having cross-sections and movable between an open flow configuration and a restricted flow configuration such that laminar flow is maintained as the flow is restricted.
2. The assembly of claim 1, further comprising a damper assembly controller coupled to the damper members.
3. The assembly of claim 1, further comprising a flow sensor coupled to the damper members, wherein the flow sensor measures pressure at less than 5 locations across the dampers.
4. The assembly of claim 1, further comprising a first sensor coupled with the first damper member, wherein the first sensor detects an orientation of the first damper member relative to the casing.
5. The assembly of claim 4, wherein the first sensor is disposed near a trailing end of the first damper member.
6. The assembly of claim 1, further comprising a first sensor coupled with the first damper member, wherein the first sensor detects an orientation of the first damper member relative to the second damper member.
7. The assembly of claim 1, further comprising an air stop.
8. The assembly of claim 1, wherein the first damper member comprises a trailing end and the second damper member comprises a trailing end, and the first damper member trailing end and the second damper member trailing end are configured to be moved toward each other when the assembly is moved toward the restricted flow configuration.
9. A damper assembly for use in a heating, ventilation, and air conditioning (HVAC) system, the assembly comprising:
- a casing having an inlet and an outflow with a flow direction extending therebetween; and
- a damper member disposed within the casing, the damper member comprising a helical body deformable between an open flow configuration and a restricted flow configuration.
10. The assembly of claim 9, wherein the damper in at least one configuration has a shape suitable for inducing a vortex in a flow within the casing.
11. A method of controlling a fluid flow in a heating, ventilation, and air conditioning (HVAC) system, comprising:
- flowing a fluid through a casing inlet toward a casing outlet;
- flowing the fluid across a plurality of damper members disposed within the casing;
- restricting an amount of the fluid passing through the casing by actuating a first damper member; and
- maintaining a laminar flow within the fluid during the actuation of the first damper member.
12. The method of claim 11, further comprising sensing an orientation of the first damper member.
13. The method of claim 11, further comprising sensing a pressure within the casing.
14. The method of claim 11, wherein restricting the amount of fluid passing through the casing comprises actuating a second damper member.
15. The method of claim 14, further comprising maintaining the laminar flow during actuation of the second damper member.
16. The method of claim 14, further comprising sensing an orientation of the second damper member.
17. The method of claim 14, further comprising sensing an orientation of the second damper member relative to the first damper member.
18. The method of claim 14, further comprising sensing an orientation of the second damper member relative to the casing.
19. The method of claim 14, wherein a cross section of the first damper member comprises an aerodynamic profile and a cross section of the second damper member comprises an aerodynamic profile.
20. The method of claim 14, further comprising sensing a distance between the first damper member and the second damper member.
Type: Application
Filed: Jan 3, 2007
Publication Date: Nov 15, 2007
Inventor: John Karamanos (San Jose, CA)
Application Number: 11/619,535
International Classification: F24F 7/00 (20060101);