This document includes subject matter that is also subject to U.S. and International copyright and trademark protection. The copyright and trademark owner grants permission to copy this document and U.S. Provisional Patent Application Nos. 62/737,251 and 62/741,690 in the U.S. Patent And Trademark Office as well as in corresponding Patent Offices but reserves all rights to the trademarks and software, data and GUI interface described herein and in U.S. Provisional Patent Application No. 62/737,251 filed Sep. 27, 2018 and U.S. Provisional Application No. 62/741,690 filed Oct. 5, 2018 including the appended drawings. Copyright © 2018, 2019 Keith Voysey and Advanced Automated Systems, Inc. of Yorba Linda, California 92887 USA.
All Rights Reserved.
The invention pertains to a system, method and device for saving energy while at the same time providing a granular control over heating and cooling of individual zones of buildings, including specifically commercial buildings. More particularly the embodiments relate to novel hybrid variable air volume (VAV) terminal units having at least one air inlet duct, a damper and at least two air outlets preferably with at least one dedicated heating coil for each outlet. The systems of the invention provide a granular zone temperature control through a master control as well as tenant control on site or remotely through a cellphone app or the internet of things (IoT). The novel method and system rely upon the novel hybrid VAV box to save energy, save installation costs by reducing VAV count and providing an automated air balancing of the entire system, as well as individual zone temperature control and provides maximum flexibility in future reconfiguration of office space.
Variable air volume terminal units (VAV boxes) are commonly used in buildings and in particular commercial buildings to provide heating, cooling and ventilation for occupants in different rooms. As illustrated in prior art
Each VAV box 11 controls a smaller area or group of offices within a floor as illustrated in
The prior art also includes VAV boxes with a single air handler (AH) inlet and multiple outlets to control temperature in different zones of a building. Examples of such prior art include Federspiel, et al. U.S. Pat. No. 8,688,243, Ring U.S. Pat. No. 4,917,174 and Ginn, et al. U.S. Pat. No. 3,934,795 each of which have multiple outlets with dampers, separate reheat coils and separate cooling coils for each outlet. The reheat coils in one of the separate ducts in the VAV are connected by a separate heating duct to a drop down register while the separate cooling coils in one of the separate ducts in the VAV are connected by a separate cooling duct to the drop down register where the warm air and cool air are mixed to meet the selected temperature requirements for the room.
Such prior art addresses the specific requirements of each zone but at the expense of a separate set of ducts and the requirement for both heating coils and cooling coils in the VAV with separate ducts. Such prior art is expensive to install and operate as it is not energy efficient and does not provide a virtual thermostat or provide the advantages of the novel hybrid VAV which utilizes a single ductwork system which is predominately found in commercial buildings which can be upgraded by adding the novel hybrid VAV. The novel hybrid VAV utilizes a single air handler inlet and at least two outlets or more outlets each of which has its own heating coil to provide a granular temperature control over each heating zone as will be described hereinafter in greater detail.
The hybrid VAV and methods and systems provided herein are the result of an extensive research effort by the inventor as illustrated by the Sep. 27, 2018 Provisional Application Ser. No. 62/737,251 and the Oct. 5, 2018 Provisional Application Ser. No. 62/741,690. The Jul. 9, 2018 attachment in Ser. No. 62/741,690 identifies options for creating a new system to provide individual zone temperature control. The Aug. 28, 2018 attachment in Ser. No. 62/737,251 represents further refinements in the new system which was not sold or offered for sale until long after the filing of the provisional applications. A novel system was subsequently installed on Dec. 6, 2018.
The prior art also includes numerous complete systems having remote controlled systems with computers and databases for saving energy such as Kuckuk, et al. U.S. Pub. 2017/0314796; Salsbury U.S. Pat. No. 8,255,085; West et al. U.S. Pat. No. 6,296,193 and Barooah et al. U.S. Pat. No. 10,047,968. Some of the prior art controls a VAV and use multiple VAVs and control the temperatures based on setpoints, load and ventilation requirements. None of the prior art employs the novel hybrid VAV. Indeed West et al. U.S. Pat. No. 6,296,193 refers to the conventional VAV boxes of Ben-Aissa et al. U.S. Pat. No. 5,558,274.
Controlling temperature from a master room 29 is particularly a problem when a slave office 47 is a corner office as illustrated in
As heretofore discussed in the prior art the air flow once it leaves the VAV Box is distributed to multiple spaces (rooms) by adjusting manual balancing dampers to control temperature based on the HVAC output. Cooling temperature control is typically based on a single room temperature and air volume either increases or decreases to control all the spaces served by a VAV box. For exterior offices heating ability is added. In the event heat is required, the VAV box air volume is reduced and heat is injected into the air stream through either a hot water coil 25 or an electric heat element. For interior offices, typically the ability to heat is not provided, heat is only achieved by not cooling (closing the air volume to its minimum setting and allowing the internal space temperature load and residual heating from exterior spaces to slowly heat the space. This traditional VAV system design while relatively inexpensive, has many drawbacks which are as follows:
The new hybrid VAV in addition solves a number of problems in the prior art including poor temperature distribution and control by a prior art VAV serving a plurality of rooms controlled by a single thermostat in a single duct system. The novel hybrid design reduces the number of VAV's required to provide a more precise control of temperature in various zones for a given amount of space. The new hybrid VAV increases the efficiency of the use of energy and when coupled to a computer and a smart phone app and/or the internet of things allows energy to be conserved by using only the minimal amount of energy where needed and when needed.
As such, there is a need in the industry for a hybrid variable air volume terminal system with multiple heating coils that is compatible with a single duct system and enhances the temperature control and area coverage of the volume terminal boxes. The novel hybrid VAV increases the area coverage that a prior art VAV box can serve and reduces the number of VAV boxes installed in a building to reduce installation, operational and energy use. The novel method and system and its control applications and smart phone apps and connection to the internet of things provides versatility in office remodeling and changes in office layout as well as energy saving in application and operation.
One implementation of the disclosed embodiments relates to the novel building management system which provides a virtual or a physical thermostat associated with each zone or room of a building served by a single duct that serves a plurality of zones or rooms. A communications interface is provided to communicate with a drop-down damper or preferably with an automated space control damper or ASCD. The communications interface operates an electrically operated damper to increase or decrease air flow from a novel hybrid VAV. The building management system includes a controller and a database that implements commands from the tenant of the space, the building manager or a controller based either on sensed use and/or a history of past usage from the database to save energy.
The air handler (AH) that serves the building includes heaters, chillers, pumps and fans to provide heating, cooling, ventilation and other services to the building. In accordance with saving energy it has been recognized and appreciated that maintaining an unoccupied building or room of a building at about 68 to 70° F. or 20 to 25° C. is the most efficient use of energy for heating and cooling. It has also been recognized and appreciated that it is more energy efficient to heat air than to cool air.
In recognizing these energy saving parameters the energy saving implementation advantages involves running the cooling cycle of an AC of an AH at around 55° F. and transporting the cooled air to a novel hybrid VAV. The novel hybrid VAV provides heating elements in each outlet of the VAV minus one heating element or coil where the outlets of the VAV are three or more to provide warmed air to each zone of a plurality of zones serviced by a single duct. The granular temperature control of each zone in the plurality of zones serviced by the single duct is preferably controlled by an electrically operated ASCD to increase or decrease the air flow and/or the temperature of the air flow from the novel hybrid VAV to increase the amount of heat added to the cooled air to match a particular thermostat setting for each individual space or collectively and individually for each room or zone.
In the winter or cold weather the AH supplies warm air at about 70° F. or 21° C. The novel hybrid VAV can also then heat this air to about 95° F. or 35° C. before distributing this heated air to the single duct distribution system. Thereafter the temperature of each single zone is modified by the tenant or occupant of the zone by changing the actual thermostat or virtual thermostat provided for that zone by increasing or decreasing flow by changing the position of the damper in the ASCD which may be either a floor or wall register but is usually a drop down damper in commercial buildings. The ASCD in alternative applications can include an optional heater or heater housing to provide additional heating, cooling and ventilation control in a particular room or zone connected to the novel hybrid VAV.
The automated space control damper ASCD together with the novel hybrid VAV box with at least two outlets one of which has a heating element results in temperature control being controlled by the ASCD and not by the traditional VAV box damper as in prior art VAV boxes. Temperature is instead controlled by the ASCD using a wired or wireless thermostat in a particular room or zone of the building. This change in the novel hybrid VAV box makes the novel hybrid VAV box operate somewhat like a constant air volume box and somewhat like a variable air volume box hence it is referred to as a hybrid VAV. Control of temperature from the ASCD provides energy saving advantages in the operation of the entire system since heating and cooling can be diverted from zones not in use to zones that are in use.
One implementation of the energy savings advantages can be achieved by providing both a sensor link and/or a communications interface to the ASCD to heat or cool an area based on actual load sensed by an electronic occupancy sensor (EOS) or a room light switch so that when the light is on signifying the room is occupied the ASCD maintains the desired room temperature. When the room is unoccupied the space is either controlled to an OFF setting or to a more energy efficient setting. The ASCD, hybrid VAV and AH can also communicate with a database to heat and cool based on anticipated future load requirements. Actual load requirements can be provided by employing a building management system BMS that employs sensors and computer control with databases to track actual building use and occupancy. Anticipated future load requirements may be provided by smart device apps connected to a communications device to prepare for an unexpected meeting outside normal business hours.
Control of temperature by the ASCD for the group of rooms also provides for a programmed or automatic recalibration of the entire group of rooms that previously required the work of an air balancer technician. After the installation or in operation of the prior art VAV the work of an air balancer technician was needed to equalize air flow to each room or zone serviced by the VAV duct so that the slave areas more or less correspond to the master area with the thermostat. This balancing might be good for one time of day (depending on diurnal heating and cooling) or one time of the year such as winter or summer but would then result in an unbalance at other times. The novel hybrid VAV in combination with the ASCD together with computer programming and a database eliminates the need for an air balancer technician. In addition, the computer and database can be programmed to provide for periodic rebalancing based on weather and thermostat settings in each zone. The prior art air balancer technician set minimum and maximum air flow settings for each office. The automated air balance system in accordance with a preferred embodiment does this automatically.
These and other advantages are achieved with a hybrid variable air volume terminal system with multiple heating coils to enhance temperature control of a plurality of rooms in a building. The hybrid variable air volume terminal system comprises a hybrid variable air volume box for a building, and a plurality of ducts coupled to the hybrid variable air volume box, each duct of the plurality of ducts comprising a heating coil operably connected thereto, and with each duct operably connected to any number of the plurality of rooms.
The novel hybrid variable air volume system can have boxes that are not rectangular in shape. Indeed any VAV box shape can be employed that is compatible with the joists or support structure beams between the ceiling and utility area between the ceiling and the next floor of the building. As a result round, polygonal, or other shaped hybrid VAV boxes may be employed depending on space. The number of outlets to the hybrid VAV box may be changed to suit requirements and at least one outlet of a hybrid VAV box can be without a heating element to provide air to either an internal area or provide an inlet to another terminal VAV box having an unheated inlet with a plurality of heated outlets. The size of the hybrid VAV box can be varied. However larger size hybrid VAV boxes are preferred with a size of about 16 inches or 40 centimeters being preferred.
In certain embodiments a wired or wireless thermostat can be used for each room or a virtual thermostat can be operably connected to the novel hybrid variable air volume terminal system to control the operation of the system remotely. In certain embodiments, the variable air volume terminal system comprises an automated air balance system and demand response control system to control and/or vary the amount of air flow into the plurality of rooms in the building.
Additional embodiments and applications will be appreciated by those skilled in the art with additional aspects and advantages deemed to be illustrative and not limiting. Such additional embodiments are illustrative only and not intended as limiting the claims to any one embodiment or application as illustrated in the accompanying drawings and Detailed Description of Certain Embodiments.
The detailed description of some embodiments of the invention will be made below with reference to the accompanying figures, wherein the figures disclose one or more embodiments of the present invention; in which:
FIG. 4A1 is a perspective partially cut away view identical to
The following detailed description includes the best mode and accompanying drawings in which like references indicate similar elements and which show specific embodiments and portions of a GUI interface for practicing the invention. The embodiments include optional and preferred embodiments to practice the invention which may be modified without departing from the scope of the invention as claimed. For example logical, mechanical, electrical, functional and system changes can be made in implementing the invention without departing from the invention. The following detailed description including best mode is not to be taken in a limiting sense, since the scope of the invention is defined in the appended claims.
In certain embodiments of the invention, the novel hybrid variable air volume terminal system comprises one or more of the following components alone or in combination: (1) a hybrid VAV Box with or without a sub plenum; (2) Dual heating coils; (3) First air distribution duct or a plurality of distribution ducts; (4) Second air distribution duct; (5) Room control dampers for first duct; and (6) Room control dampers and preferably automated space control dampers (ASCD) for second duct.
Referring now to
Hybrid VAV 10 includes a sub plenum 30 disposed between the plurality of outlets and a terminal wall 36 opposite inlet 12 to equalize air flow and reduce noise. The size of the sub plenum is approximately 10% to 20% of the interior space of the novel hybrid VAV. Hybrid VAV 10 has at least two or more outlets 14 and 16 but may have one less heating element 22A or 22B than the total number of outlets. Where the novel hybrid VAV includes an outlet each with a heating element 22A and 22B a single duct 32 and 34 connect the hybrid VAV 10 to a separate group of offices with each office having its own ASCD or automated space control damper 40A, 40B, 40C and each of which control temperature in duct 32 which ASCD dampers 40E, 40F, 40G and 40H control temperature in duct 34 as illustrated in
Referring now to
Comparing now prior art
The novel hybrid VAV box can be configured in a number of different ways as illustrated in
In one embodiment, a single hybrid VAV box (10) feeds two or more ducts (14, 16). Each duct can have a heating coil (22) operably connected thereto. Conditioned air is then delivered to individual temperature controlled rooms by ASCD control dampers (40). This assembly can be installed as many times as needed throughout the building. The hybrid VAV box air flow is controlled to maintain a static duct pressure setpoint
Referring now to prior art
Referring now to
In certain embodiments and a preferred application, the hybrid variable air volume terminal system comprises an automated air balance system and demand response control system to control and/or vary the amount of air flow into the plurality of rooms in the building by the ASCD. In the prior art once the system is installed the air balance remains the same until a technician comes out and rebalances the system. As a result seasonal and even diurnal changes can make a static air balanced system feel uncomfortable particularly prior art master slave air balanced systems. The dynamic air balance system provided by the novel VAV 10 and ASCD 40.
Referring now to
In the dynamic air balancing embodiment, the hybrid variable air volume terminal system comprises an automated air balance system due to its ability to isolate individual rooms. In certain embodiments, the automated air balance system comprises one or more of the following: (1) Minimum CFM drop damper position (based on measured airflow); (2) Maximum CFM drop damper position (based on measured airflow); (3) Maximum noise CFM drop damper position (based on setting or diffuser design); (4) Drop damper position/CFM calculation (created during balance); (5) hybrid VAV box static pressure setpoint calibration (created during balance); (6) Automated hybrid VAV two point CFM calibration to precision flow hood; and (7) Automated balance report.
The novel hybrid and ASCD combination not only provides for a dynamic balancing but also provides a database as illustrated in
Referring now to
The advantages of the embodiments are further enhanced with an energy saving building management system BMS as illustrated in
In a further energy saving embodiment, a demand response control system may be added to permit the following stages of the system: (1) First stage: Turn off all air in rooms that are not occupied and are being controlled using temperature setback; (2) Second stage: Raise room temperature setpoints in non-critical common areas (i.e. kitchens, break rooms, storage areas, etc.); and (3) Third stage: Raise room temperature setpoints in occupied offices.
In certain embodiments, the variable air volume terminal system comprises a virtual office thermostat configured to operate with or without the VAV box described in certain embodiments. The virtual office thermostat provides a web service that allows the office occupant of a building or building personnel using a smartphone, tablet, or desktop computer to view and control their own individual office space. Virtual thermostats are connected/interfaced into the building BMS system via a web or thick client application.
In certain embodiments, the office occupant, building personnel or other user can access and/or control any one of the following using the virtual office thermostat: (1) Room temperature setpoint (includes single and dual set points); (2) Lighting level setpoint; (3) Arrival and departure times; (4) Request after-hour services (includes HVAC and/or lighting); (5) Adjust temperature setpoint limits (Building Staff Only); (6) Adjust setup (Building Staff Only) includes minimum airflow setting, maximum airflow setting, K factor setting, box/damper size settings); (7) Invoke air balance mode (Building Staff Only), which temporarily disables thermostat limits; (8) Displays and notifies the tenant through this web service when a utility company invokes demand response. The system raises its personal setpoint to reduce energy consumption; and (9) 100% onboard, which requires only the user's first and last name, plus email address and/or cell phone number.
In certain embodiments, energy savings are realized through the use of the hybrid variable air volume terminal system with the following characteristics: (1) Individual office solar temperature reset; (2) Individual office de-occupy temperature setback; (3) Individual office afterhours control; (4) Multiple demand response levels when for example a utility company announces a power reduction; (5) Prevents overcooling and overheating of all areas; (6) By backing down each area, it dramatically reduces fan and heating/cooling energy; and (7) Due to all interior zones' ability to heat, faster warmup times are achievable.
In certain embodiments, the hybrid variable air volume terminal system provides an enhanced occupant experience with the following characteristics: (1) Each room and common area has individual temperature control through a virtual thermostat; (2) Easy intuitive software application for preference adjustments (virtual thermostat & lighting control); and (3) Remote individual controllability (can be set before arriving). In certain embodiments, the variable air volume terminal system provides an enhanced building personnel experience with the following characteristics: (1) Granular control provides for superior remote trouble shooting capability; (2) 3D control graphics are intuitive and easy to use; and (3) Comfort Control software application provides complete control and setup functionality.
In certain embodiments, the variable air volume terminal system provides enhanced system functionality with the following characteristics: (1) Intelligent Controlled Cool Down/Warmup is based on past room occupancy as illustrated in
It shall be appreciated that the variable air volume terminal system allows one novel hybrid VAV zoning box to perform the work of multiple prior art VAV boxes. This combined with automated air balance, downstream controlled room dampers, virtual thermostats and enhanced sequences reduces the overall cost and increases the overall effectiveness of the temperature control.
The variable air volume terminal system comprises the following advantages: (1) Reduces the cost of air distribution systems while providing better control for commercial buildings; (2) System provides tenants with an intuitive interface (looks like a thermostat) to interact with the building's mechanical system; (3) System provides building personnel with a convenient tool to setup and control the building; and (4) Superior energy savings can be achieved due to the system's design.
It shall be appreciated that the variable air volume terminal system's use of a dual or multiple duct heating coil design with downstream room control dampers allows for twice the area coverage and superior control. In a 30,000 square foot commercial building that requires the installation of approximately 33 VAV boxes, the volume terminal system can be installed in the same building using approximately 11 VAV boxes. As such, cost advantages can be realized through the use of the variable air volume terminal system.
Referring now to
A control circuit is illustrated in
Referring now to
It shall be appreciated that the components of the variable air volume terminal system described in several embodiments herein may comprise any alternative known materials in the field and be of any color, size and/or dimensions. It shall be appreciated that the components of the variable air volume terminal system described herein may be manufactured and assembled using any known techniques in the field.
Persons of ordinary skill in the art may appreciate that numerous design configurations may be possible to enjoy the functional benefits of the inventive systems. Thus, given the wide variety of configurations and arrangements of embodiments of the present invention, the scope of the invention is reflected by the breadth of the claims below rather than narrowed by the embodiments described above.
The application is related to and entitled to priority based on the subject matter disclosed in U.S. Provisional Patent Application Ser. No. 62/737,251 filed Sep. 27, 2018 and U.S. Provisional Application Ser. No. 62/741,690 filed Oct. 5, 2018 which are incorporated herein by reference in their entirety.
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