This disclosure relates to a heater device, system and method for providing supplemental heat for a heating system. More specifically, a supplemental heating device for an air source variable refrigerant flow system operating in cold weather climates is described herein.
Air source Variable Refrigerant Flow (VRF) systems are gaining market share in moderate climates. Components of the VRF system are the outdoor (condensing) unit, the indoor unit, refrigerant, and where applicable the heat recovery unit. Many VRF systems provide heating and cooling directly from air source heat pumps to fan coils in building zones. The variable speed of VRF systems allow the amount of refrigerant sent to each zone to be modulated independently in tune with changing space loads. VRF systems typically provide energy savings in comparison to other heating systems. Some VRF systems may provide savings of $0.20/ft2 to $0.40/ft2 of building area.
Currently, systems with air source heat pumps are not widely used in cold climates because they lose capacity due to low ambient air conditions. For outdoor temperatures between 0° F. and 35° F., the units operate at approximately 30% below their rated heating efficiency. At temperatures less than −10° F., the ratio rapidly decreases resulting in significant heating efficiency degradation. For this and other reasons, additional heating appliances or systems must be added directly to the heated space (i.e., furnaces, boilers, engines with ductwork and/or vents discharging heat into the heated space). These technologies typically have lower efficiencies, higher transport losses, require additional space, and can contribute to higher overall system costs.
In present cold climate installations, heat pumps are either not considered for the application or are located indoors (mechanical rooms) to keep components of the heat pump from freezing and to ensure the heat pump operates at acceptable efficiencies. Being limited to indoor installations may increase transport losses, installment costs, and material costs due to the addition of linear feet of refrigerant lines/hoses.
Therefore, there is a need in the art for a more efficient and cost-effective heating system and supplemental heating device. The supplemental heating device may comprise an assembled unit that allows existing VRF systems to be utilized in cold climates.
The present disclosure includes a system, method, and devices related to a supplemental heating system. These systems are described in greater detail below, and any combination of elements and/or methods are contemplated as aspects and embodiments of the overall invention.
Disclosed herein is a supplemental heating system for a primary heating device, the supplemental heating device comprising an upper enclosure housing a controller and a supplemental heating element, at least one temperature sensor communicatively coupled to the controller, a lower enclosure, an inlet damper disposed on the lower enclosure, an outlet damper disposed on the upper enclosure, and an intermediate damper disposed between the upper enclosure and the lower enclosure, wherein the controller operatively generates instructions to open or close at least one of the inlet damper, the outlet damper, and the intermediate damper to direct airflow based on at least one of input from the at least one temperature sensor or a state of the supplemental heating element. In an embodiment, the at least one temperature sensor comprises an external temperature sensor disposed external to the upper enclosure and the lower enclosure to operatively measure an outdoor temperature. The at least one temperature sensor may further comprise a discharge temperature sensor disposed internal to at least one of the upper enclosure or the lower enclosure, and downstream of the supplemental heating element. The controller may operatively modulate a heating input of the supplemental heating element based on measurements received from the discharge temperature sensor. In another aspect, the controller may operatively generate instructions to close the inlet damper and the outlet damper in response to the at least one temperature sensor. The at least one temperature sensor may comprise a discharge temperature sensor disposed internal to at least one of the upper enclosure or the lower enclosure, and downstream of the supplemental heating element. The controller may generate instructions to close the inlet damper, close the outlet damper, and open the intermediate damper in response to the external temperature sensor determining that the outdoor temperature meets or is below a threshold temperature. The controller may generate instructions to close the inlet damper, close the outlet damper, and open the intermediate damper in response to the external temperature sensor determining that the outdoor temperature exceeds a threshold temperature.
Also described herein is a method of controlling a supplemental heating system for a primary heating system, the method comprising monitoring an outdoor temperature via a sensor, determining whether the outdoor temperature reaches a lower limit, in response to determining the outdoor temperature reaches a lower limit, closing an inlet damper and an outlet damper, and circulating tempered air heated by the supplemental heating system, determining whether the outdoor temperature passes above the lower limit, and in response to determining the outdoor temperature passes above the lower limit, opening the inlet damper and the outlet damper, and terminating heating by the supplemental heating system. The method may further comprise sensing, via a second temperature sensor, a temperature of the circulating tempered air heated by the supplemental heating system, and modulating a supplemental heat source based at least in part on the sensed temperature of air supplied to the primary heat source. In at least one embodiment, the method may further comprise modulating the supplemental heat source based at least in part on the sensed temperature of air supplied to the primary heat source and a temperature setting. The temperature setting may be based on an operating capacity of the primary heating system. The method may further comprise wirelessly communicating the outdoor temperature from the sensor to a controller. The method may further comprise wirelessly communicating the temperature of the circulating tempered air from the second sensor to a controller. The method may further comprise, in response to determining the outdoor temperature reaches a lower limit, opening an intermediary damper. The method may further comprise, in response to determining the outdoor temperature passes above the lower limit, closing an intermediary damper.
Disclosed herein is a supplemental heating system for a primary heating device, the supplemental heating device comprising an enclosure that operatively encloses a primary heating device, a supplemental heat source, one or more dampers disposed on or within the enclosure, and a controller and one or more temperature sensors, wherein the controller is communicatively coupled to the one or more temperature sensors to operatively control the supplemental heat source and the one or more dampers based on measurements received from the one or more temperature sensors. The controller may receive input to adjust temperature limits associated with the one or more temperature sensors. In another aspect, the controller may receive input to adjust settings associated with the supplemental heat source and stores the settings in a memory. The one or more temperature sensors may comprise an external temperature sensor disposed external to the enclosure and beneath a cover that operatively shields the external temperature from ambient light.
The foregoing embodiments are merely exemplary of some of the aspects of the system. Additional features and elements may be contemplated and described herein. Also, features from one of the foregoing embodiments may be combined with features from any of the other foregoing embodiments.
Reference will now be made in detail to exemplary embodiments of the present invention, examples of which are illustrated in the accompanying drawings. It is to be understood that other embodiments may be utilized and structural and functional changes may be made without departing from the respective scope of the invention. Moreover, features of the various embodiments may be combined or altered without departing from the scope of the invention. As such, the following description is presented by way of illustration only and should not limit in any way the various alternatives and modifications that may be made to the illustrated embodiments and still be within the spirit and scope of the invention.
As used herein, the words “example” and “exemplary” mean an instance, or illustration. The words “example” or “exemplary” do not indicate a key or preferred aspect or embodiment. The word “or” is intended to be inclusive rather than exclusive, unless context suggests otherwise. As an example, the phrase “A employs B or C,” includes any inclusive permutation (e.g., A employs B; A employs C; or A employs both B and C). As another matter, the articles “a” and “an” are generally intended to mean “one or more” unless context suggests otherwise.
“Logic” refers to any information and/or data that may be applied to direct the operation of a processor. Logic may be formed from instruction signals stored in a memory (e.g., a non-transitory memory). Software is one example of logic. In another aspect, logic may include hardware, alone or in combination with software. For instance, logic may include digital and/or analog hardware circuits, such as hardware circuits comprising logical gates (e.g., AND, OR, XOR, NAND, NOR, and other logical operations). Furthermore, logic may be programmed and/or include aspects of various devices and is not limited to a single device. Furthermore, the terms “user,” “customer,” “consumer,” and the like are employed interchangeably throughout the subject specification, unless context suggests otherwise or warrants a particular distinction among the terms. It is noted that such terms may refer to human entities or automated components supported through artificial intelligence (e.g., a capacity to make inference). As such, embodiments may describe a user action that may not require human action.
Disclosed embodiments may include user interfaces. As used herein, a user interface may include devices that receive input from a user and transmit the input to electronic circuitry, such as a microprocessor, or outputs information to a user. Such user interfaces may include buttons, switches, knobs, touch screens (e.g., capacitive touch screens), microphones, image capturing devices, motion sensors, pressure sensors, a display screen, a speaker, a light (e.g., LED, bulb, etc.), or the like. For brevity, examples may be described with reference to a user interface in general rather than any particular type of user interface. It is noted, however, that controllers for the supplemental heating devices may include multiple user interfaces of various types. Moreover, described embodiments may be utilized with various types of heat pumps. In at least one example, a heating system may comprise a heat pump that does not communicate with a supplemental heating device. As such, the supplemental heating device may be attached to or otherwise utilized with heat pumps of various makes and models without requiring modification to the heat pumps.
Networks or communication networks may include wired or wireless data connections to a network (e.g., Ethernet, Wi-Fi, cellular network, local area connections, etc.). Embodiments, for example, may utilize various radio access networks (RAN), e.g., Wi-Fi, Wi-Fi direct, global system for mobile communications, universal mobile telecommunications systems, worldwide interoperability for microwave access, enhanced general packet radio service, third generation partnership project long term evolution (3G LTE), fourth generation long term evolution (4G LTE), third generation partnership project 2, BLUETOOTH®, ultra-mobile broadband, high speed packet access, xth generation long term evolution, or another IEEE 802.XX technology. BLUETOOTH (in any of its various iterations), various wireless technologies for exchanging data over short distances (e.g., ZigBee, RuBee, DASH7, etc.), and other protocols and personal area networks may be utilized. Wireless communication may also include, in whole or in part, communications transmitted over more traditional local area networks or cellular data networks, so as to incorporate aspects of cloud-based computing systems, information available via world wide web and other internet connectivity, and the like. As such, any indication of “wireless,” “Wi-Fi,” or other similar terminology should be read expansively (at least within the context it is used) throughout this disclosure. Moreover, embodiments may use one or more different communications protocols or devices (whether wired or wireless) to communicate between the various components of the system.
In some traditional climate control systems, an external heating unit is located on a roof of a building or at another location. The external heating unit may be a VRF device that is connected to various indoor units in a building. The VRF device is located externally to the building and exposed to the external climate. These VRF devices can lose efficiency in cold weather. As such, buildings in cold climates often use other types of heating devices instead of or in conjunction with VRF devices. These other types of heating devices are typically less efficient and add increases in costs, space requirements, materials, and the like.
Embodiments described herein may provide a supplemental heating device that is attached to the outdoor unit. The supplemental heating device may selectively apply heat at low ambient air temperature conditions. For instance, the supplemental heating device may be operatively attached to a VRF device. The supplemental heating device may comprise a housing, heating element, controller, and one or more dampers. The controller may generate instructions to position the dampers according to whether the supplemental heating device is in an “on” or “idle” state. In an on state, the controller operatively positions the dampers so that air is heated by the heating element prior to the air entering an intake of the VRF device. In the off state, the controller operatively positions the dampers so that the VRF device receives the air from an external environment without the supplemental heating device heating the ambient air. Accordingly, the described embodiments may minimize or reduce the effect of low ambient temperature and may provide for appropriate heat pump operation and performance at those low ambient air temperature conditions.
It is noted that described supplemental heating devices may be separately constructed with respect to the VRF device. As such, the supplemental heating devices may be attached to existing VRF devices without modification to the VRF device. Moreover, the supplemental heating devices may comprise dedicated controllers that are independent of a VRF device's controller. As such, the supplemental heating device may be modified, controlled, or installed separate from the VRF device. Moreover, the supplemental heating devices may be modified to be attachable to VRF devices of various makes and models.
Turning now to
The supplemental heating device 102 may primarily comprise an enclosure 110 (which may include upper enclosure 106 and lower enclosure 108) and a heat exchanger element 140. The enclosure 110 may house the heat exchanger element 140 and other operative components. In an aspect, the enclosure 110 may comprise a metal, plastic, or other material and may be a generally weatherproof enclosure (which may include rain gutter 150). The lower enclosure may include outside air intake louver 128, a drain pan 116 that may drain condensation or other liquids, and a coil access door 126 that may allow access to one or more components of the heating system 100.
The enclosure 110 may comprise one or more dampers that may be opened or closed to manipulate airflow. In an example, the enclosure 110 may comprise three dampers, such as an inlet damper 114, outlet damper 132, and intermediate damper 136. A controller 160 may be disposed within the enclosure 110 and may operatively control one or more motors or actuators (not shown) to open or close the inlet damper 114, outlet damper 132, or intermediate damper 136. While embodiments may simply refer to the controller 160 opening/closing a damper, it is noted that the controller 160 generally controls a motor or actuator, which in turn opens or closes the dampers.
The inlet damper 114 selectively prevents or allows the outdoor air to enter the enclosure 110. When in an open position, the inlet damper 114 allows the outdoor air to enter the enclosure 110 and traverse through the primary heating device 104. In the closed position, the inlet damper 114 does not allow cold outdoor air to enter the enclosure 110.
The outlet damper 132 may be positioned proximal an outlet hood 112. Positioning of the outlet damper 132 selectively prevents or allows tempered air to escape the primary heating device 104 in the enclosure 110. For instance, when in the open position the outlet damper 132 allows air to pass from the inlet damper 114 through the enclosure 110 and through the outlet damper 132 to the outside environment. In a closed position, the outlet damper 132 may generally prevent airflow from exiting the enclosure 110. In a closed position, the outlet damper 132 may force tempered air to recirculate back to the heat exchanger element 140 inside the enclosure 110.
The intermediate damper 136 may be located on or at a divider wall separating the lower enclosure 108 and inlet damper 114 from the upper enclosure 106 and the outlet damper 132. The inlet damper 114 may be closed to prevent air from passing from the inlet damper 114 to the heat exchanger element 140, inside supplemental heat device 102. In the open position, the inlet damper 114 allows air to circulate between the lower housing 108, to the primary heating unit 104 (e.g., entering the primary inlet 105 and exiting the primary exhaust 125), to the upper enclosure 106 and through the heat exchanger element 140.
Heat exchanger element 140 is located in the upper enclosure 106 and may be separated from the exhaust 125 via an insulated wall 120 (e.g., a foil face insulated wall). The heat exchanger element 140 generally includes heat controller 142, tubes or coils 144, exhaust 116, and intake 148. It is further noted that the heat exchanger element 140 may comprise a gas heating device that includes a gas intake 152. In an aspect, the controller 142 may be separated from the rest of the upper enclosure 106 by wall 147. When the supplemental heating device 102 is circulating tempered air, the coils 144 are located on the discharge side of the exhaust 125 of the primary heating device 104 downstream of the outlet air damper 132 and upstream of the intermediate air damper 136 (as shown by the solid airflow line in
The outdoor air temperature sensing probe 192 (as shown in
The discharge air or temperature sensor 194 is located upstream of primary heating device 104 and downstream of the intermediate damper 136 and inlet air damper 114. It is noted that the discharge air sensor 194 communicatively coupled to the controller 160 (e.g., wirelessly or wire coupled to the controller 160). According to embodiments, the discharge air sensor 194 senses the temperature of the circulating air just before it traverses through the primary heating device 104. Based on the temperature range, the controller 160 will modulate the heating input to the heat exchanger element 140 to supply the necessary Btu loadings to the circulating air (shown as solid line in
Turning to
In an aspect, the lower enclosure 708 may comprise one or more side panels 720. The side panels 720 may be operatively attached together. In another aspect, the side panels 720 may be operatively attached to a bottom panel (not shown). As an example, the side panels 720 and bottom panel may be shipped to a desired location as separate pieces. This may reduce shipping size and may allow for easier transportation in comparison to shipping the lower enclosure 708 as a fully constructed unit. Accordingly, the side panels 720 and bottom panel may be assembled around the primary heating device 704 after (or concurrently with) the primary heating device 704 is installed. Lower enclosure 708 may be designed to attach to any make or model of the primary heading device 704.
As shown in more detail in
In at least one embodiment, the system 700 may include a support rail 774 that may be attached to the primary heating device 704 or at least one of the side panels 720. The support rail 774 may interface with at least a portion of the flange 770.
In view of the subject matter described herein, methods that may be related to various embodiments may be better appreciated with reference to the flowchart of
The method 1400 may provide for operation of a primary heating device or heat pump when outdoor air conditions are satisfactory for optimal performance. At 1402, in an idle or open state, the method 1400 opens an inlet air damper, opens an outlet air damper, and closes an intermediate air damper. In some instances, a system may already be in an idle state at 1402 and the method 1400 may maintain the positions of the dampers.
It is noted that a controller may operatively control one or more motors that position the dampers. This allows outdoor air to enter the enclosure, traverse through the heat pump coil, and be discharged back to the outdoors through the outlet air damper. No recirculation of the air is allowed by the dampers in this condition. This operating method allows the heat pump to operate as if it was a standalone appliance.
Moreover, at 1402 the method may utilize one or more sensors to determine a position of one or more dampers. For instance, the method 1400 may utilize proximity sensors, reed switches, transducers, solenoid sensors, or the like to determine whether a damper is open or closed. Determining the position may allow the method 1400 to determine whether a system is appropriately functioning and/or may allow a system to diagnose one or more issues when the system is not properly functioning.
At 1404, the method 1400 monitors an outdoor temperature and determines whether the outdoor temperature reaches a lower limit. The lower limit may be predetermined for efficient heat pump performance or may be dynamically determined based on a history associate with the heat pump performance. If the lower limit is not reached, the method 1400 may continue to monitor the outdoor temperature. If the lower limit is reach, the method 1400 may continue at reference number 1406.
At 1406, the method 1400 closes the inlet damper, closes the outlet damper and opens the intermediate damper. This operating method enables the ambient air inside the enclosure to recirculate continuously as described herein. Air is discharged from the heat pump circulating fan, bypasses the closed outlet air damper, traverses the supplemental heating element, progresses through the intermediate air damper, bypasses the closed inlet air damper, and then traverses through the heat pump coil. Operation is maintained continuously.
At 1408, the method 1400 monitors an outdoor temperature and determines whether the outdoor temperature is above the lower limit. If it is not above the limit, the method continues at 1406. If above the lower limit, the method may continue at 1402. For example, until the outdoor air temperature outside the enclosure increases above the low limit of the outdoor air sensing probe for adequate heat pump performance.
At 1410, the method 1400 monitors circulating air temperature to determine whether the circulating air temperature is at the desired supply temperature setting. It is noted that the systems described herein may utilize one or more sensors positioned to operatively sense the circulating air temperature. Moreover, the method 1400 may open or close dampers, turn on/off a heat source, or the like.
It is further noted that the method 1400 may modulate the supplemental heating element, such as through logic built into the controller of the supplemental heating element. A satisfactory temperature range may be selected for ambient air conditions inside the enclosure for optimal heat pump performance. Once the circulating air within the enclosure is established, the discharge air sensing probe senses the temperature of the circulating air just before it traverses through the heat pump coil. Based on the temperature range, the heating element control will modulate the heating input to the heat element to supply the necessary Btu loadings to the circulating air based on the heat pump operating capacity. This keeps the circulating air supplied to the heat pump coil at satisfactory temperature values. This allows the heat pump to produce the needed heat load to the indoor system during extreme cold outdoor temperatures. By modulating the heat input to the heating element, the amount of fuel or electricity needed to operate the supplemental heating device and enclosure is minimized while increasing the operating efficiency of the heat pump. This reduces operational costs of the entire system during cold weather conditions.
With this method, the heat exchanger element modulating control and the air damper control are adjustable in nature. Each control can be adjusted independently to achieve optimal performance of the entire system. The acting outdoor ambient temperature value enabling the air damper control can be altered by adjusting the outdoor air sensing probe temperature value. The modulating control for the heating element can be adjusted to give a wide temperature range of circulating air to the heat pump coil. This is done by adjusting the temperature range, sensitivity of the discharge air sensing probe, and/or delay time before enabling or disabling stages of heat. Based on location of the heat pump in different cold weather climates, each installation can be adjusted to different settings to achieve the optimum performance for that specific system.
Safeties are integrated into the controls to ensure proper operation of the entire system. Air damper end switches and an airflow proving device guarantee airflow across the heating element during heat loading operation. Without the proof of closures of these safeties the air dampers will stay in the idle condition to allow normal operation of the heat pump. High temperature limit switches are installed and integrated into the heat element control. This ensures that at no time will the integrity of the heat pump, heating element, enclosure, and enclosure components be susceptible to overheating.
This method is intended to be completely external to the heat pump logic and control. This supplemental heating device and enclosure is kept separate to allow for the adjustability and adaptability of the supplemental system in any and all climates and applications.
The method outlined controls the ambient air in the housing around the heat pump coil by an enclosure. By utilizing this method, standalone heat pumps may be utilized in extreme cold outdoor climates, while providing the benefits of energy savings and increased appliance efficiency over the entire year on average.
In some embodiments, control of the dampers, heating limits, and heating elements may utilize processing techniques, such as artificial intelligence, statistical models, or other processes and/or algorithms. These high level-processing techniques can make suggestions, provide feedback, or provide other aspects. In embodiments, a master control may utilize classifiers that map an attribute vector to a confidence that the attribute belongs to a class. For instance, a master control may input attribute vector, x=(x1, x2, x3, x4, xn) mapped to f(x)=confidence (class). Such classification can employ a probabilistic and/or statistical based analysis (e.g., factoring into the analysis sensed information and heating attributes) to infer suggestions and/or desired actions. In various embodiments, a controller may utilize other directed and undirected model classification approaches including, e.g., naive Bayes, Bayesian networks, decision trees, neural networks, fuzzy logic models, and probabilistic classification models providing different patterns of independence. Classification may also include statistical regression that is utilized to develop models of priority. Further still, classification may also include data derived from another system, such as automotive systems.
In accordance with various aspects, some embodiments may employ classifiers that are explicitly trained (e.g., via a generic training data) as well as implicitly trained (e.g., via observing user behavior, user interaction with components, user preferences, historical information, receiving extrinsic information). For example, support vector machines may be configured via learning or training phase within a classifier constructor and feature selection module. Thus, the classifier(s) may be used to automatically learn and perform a number of functions, including but not limited to determining, according to historical data, suggestions for gain and/or sensitivity settings. This learning may be on an individual basis, i.e., based solely on a single heating system, or may apply across a set of or the entirety of heating systems. Information from the users may be aggregated and the classifier(s) may be used to automatically learn and perform a number of functions based on this aggregated information. The information may be dynamically distributed, such as through an automatic update, a notification, or any other method or means, to the entire heating system base, a subset thereof or to an individual heating system.
As used herein, the terms “component,” “module,” “system,” “interface,” “platform,” “service,” “framework,” “connector,” “controller,” or the like are generally intended to refer to a computer-related entity. Such terms may refer to at least one of hardware, software, or software in execution. For example, a component may include a computer-process running on a processor, a processor, a device, a process, a computer thread, or the like. In another aspect, such terms may include both an application running on a processor and a processor. Moreover, such terms may be localized to one computer and/or may be distributed across multiple computers.
While methods may be shown and described as a series of blocks, it is noted that associated methods or processes are not limited by the order of the blocks. It is further noted that some blocks and corresponding actions may occur in different orders or concurrently with other blocks. Moreover, different blocks or actions may be utilized to implement the methods described hereinafter. Various actions may be completed by one or more users, mechanical machines, automated assembly machines (e.g., including one or more processors or computing devices), or the like.
This application claims priority to U.S. Provisional Patent Application No. 62/665,787 entitled “SUPPLEMENTAL HEATING DEVICE AND METHOD,” filed on May 2, 2018, which is incorporated herein by reference in its entirety.
Filing Document | Filing Date | Country | Kind |
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PCT/US19/30348 | 5/2/2019 | WO | 00 |
Number | Date | Country | |
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62665787 | May 2018 | US |