Patent Application
20090211644
Not applicable to this application.
1. Field of the Invention
The present invention relates generally to water heater systems and more specifically it relates to an instant hot water delivery system for efficiently heating water when necessary to provide instant hot water to a faucet.
2. Description of the Related Art
Any discussion of the related art throughout the specification should in no way be considered as an admission that such related art is widely known or forms part of common general knowledge in the field.
Hot water heaters have been in use for years and are used in many homes and buildings. Generally, however, prior hot water heaters have lacked in various areas. One problem currently exists and is noticeable when an individual turns on the hot water faucet to get hot water. Generally, the user must wait several seconds for the hot water to arrive, wherein during that time, cold or warm water flows through the faucet. This can cause a large amount of water waste, especially when multiplied by thousands of homes all experiencing the same problem.
Another problem with current water heaters is that the water heater generally maintains a constant hot temperature of the water within the water heater tank at all times, thus wasting energy during the times when the user does not desire or need hot water, such as but not limited to when the user is sleeping, at work, or on vacation. This can drastically increase energy costs, as well as waste electricity. Because of the inherent problems with the related art, there is a need for anew and improved instant hot water delivery system for efficiently heating water when necessary to provide instant hot water to a faucet.
The general purpose of the present invention is to provide an instant hot water delivery system that has many of the advantages of the water heater systems mentioned heretofore. The invention generally relates to a water heater system which includes a water heater including an inlet and an outlet, a cold water supply line introducing cold water into the inlet, a hot water supply line connecting the outlet to a faucet and a recirculation line connected to the hot water supply downstream of the outlet and the cold water supply line upstream of the inlet. The recirculation line forms a first recirculation loop for water within the water heater to flow during a first water heating process. A recirculation pump is connected to the cold water supply line between the local recirculation line and the inlet for circulating the water during the water heating process.
There has thus been outlined, rather broadly, some of the features of the invention in order that the detailed description thereof may be better understood, and in order that the present contribution to the art may be better appreciated. There are additional features of the invention that will be described hereinafter and that will form the subject matter of the claims appended hereto.
In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction or to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of the description and should not be regarded as limiting.
An object is to provide an instant hot water delivery system for efficiently heating water when necessary to provide instant hot water to a faucet.
Another object is to provide an instant hot water delivery system that reduces energy consumption and water usage
Another object is to provide an instant hot water delivery system that may be retrofitted to an existing water heater system or installed with a new hot water system.
An additional object is to provide an instant hot water delivery system that only heats the water during specific preprogrammed times and days.
A further object is to provide an instant hot water delivery system that includes a local recirculation method to quickly heat the water within the system.
Another object is to provide an instant hot water delivery system that may be used in commercial or residential properties.
Another object is to provide an instant hot water delivery system that provides nearly instant hot water to a water usage location, such as a faucet.
Other objects and advantages of the present invention will become obvious to the reader and it is intended that these objects and advantages are within the scope of the present invention. To the accomplishment of the above and related objects, this invention may be embodied in the form illustrated in the accompanying drawings, attention being called to the fact, however, that the drawings are illustrative only, and that changes may be made in the specific construction illustrated and described within the scope of the appended claims.
Various other objects, features and attendant advantages of the present invention will become fully appreciated as the same becomes better understood when considered in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the several views, and wherein:
Turning now descriptively to the drawings, in which similar reference characters denote similar elements throughout the several views,
The hot water heater 20 is used to heat and possibly store the water in the system. The hot water heater 20 generally includes an insulated tank 21, a heating element 27, a pressure relief valve and a thermostat among other electrical and mechanical components common to hot water heaters, such as but not limited to a sacrificial anode to prevent corrosion of the tank, drain valves, and shutoff valves. The hot water heater 20 may be preexisting or may be newly installed with the present invention, as well as any other components described herein that assist in the function of the present invention.
It is appreciated that the hot water heater 20 may by a tank style, as described above, or tankless style configuration. The heating element 27 may be comprised of an electric heating element 27 or a gas burner and valve configuration. Other configurations may also be utilized for the heating element 27 all of which heat the water within the hot water heater 20. The pressure relief valve prevents over pressurization of the tank 21, wherein the relief valve will open when the tank 21 exceeds a certain threshold. The relief valve exists to prevent the tank 21 from over pressurizing and possibly rupturing. The thermostat is used for regulating the temperature of the water within the tank 21.
It is appreciated that the tank style water heater also generally has first dip tube 25 for allowing cold water to enter the tank 21 through the inlet 22 and a second dip tube 23 for allowing hot water to exit the tank 21 through the outlet 24. Since cold water is denser than hot water, the cold water dip tube 23 extends deeper into the tank 21 than the hot water dip tube 25.
It is appreciated that in a tankless water heater system, a heating element 27 is generally used with a heat-exchanging interface for transferring heat to the water in the form of coils, etc., and a flow sensing and controlling device is used to sense the flow of water through the heat-exchanging interface and to enable the heating element 27. The coils are generally comprised of highly conductive material for quickly and efficiently heating the water. Various other configurations of hot water heaters 20 may be used and integrated with the present invention.
The present invention includes a control unit 30 to control when the hot water heater 20 is heating the water via the heating element 27 and to turn the pump 40 on and off. The control unit 30 includes a user interface 32 and a display 38, such as a digital LCD display that can show numbers, pictures, letters, etc., for allowing the user to program water heating schedules, recirculation pump 40 shutoff temperatures, recirculation pump 40 timeouts, water heater set temperatures, recirculation pump 40 speeds, heating element 27 on and off positions, activation of the three-way valves 70, 72 and bypass valves 60, and various other settings. The control unit 30 may connect to the various components of the present invention remotely, through connecting wires 39 or various other means.
The user interface 32 preferably includes, but is not limited to, a keypad, rotating knob 34 for increasing or decreasing a setting, buttons 35 including left, right, previous, and next cursor arrows, time and mode buttons 35, on and off switches 36, slider bar 33 for selecting the day of the week for hot water scheduling, or anything else that allows for control of the control unit 30. The control unit 30 also is able to communicate with and/or control the hot water heater 20, the recirculation pump 40, the bypass valves 60, pump enable units 64, and various other electrical circuitry of the present invention.
The heat scheduling feature of the control unit 30 allows for the user to program what times and days to heat the water within the tank 21 of the hot water heater 20. During non-use hours, the water heater 20 will be set to an idle state where the water is not heated at all or is only heated minimally to prevent freezing. It is appreciated that the scheduling control may not be necessary with a tankless water heater 20. The control unit 30 may also communicate or receive signals from the thermostat within the hot water heater 20.
The control unit 30 may also include various safety features, such as shutoff timeouts for recirculation times, battery backup in case of power failure, audible alarms for over-temperature conditions, etc. The control unit 30 may also be surrounded by an enclosure 31 for protection, wherein the enclosure 31 is water resistant. The control unit 30 may further include a cover panel or other locking mechanism to prevent tampering with the control unit 30.
The present invention includes a recirculation pump 40 for transferring the water through the pipes. The recirculation pump 40 is generally comprised of, but is not limited to, a centrifugal configuration and includes a motor 43, which may be electrically powered or may be powered through other means, connected to an impeller 44 for transporting the water or other fluid.
The pump also includes an enclosure 41 through which the water flows to contact the impeller 44 and to which connects the pump to the adjacent pipes. The recirculation pump 40 may further have a temperature sensor embedded which tells the control unit 30 when the water in the recirculation loop has reached the desired temperature and therefore when to turn the recirculation pump 40 off. The recirculation pump 40 is used during both heating processes (first and second) and is fluidly connected to both the first recirculation loop and the second recirculation loop
Various pump enable units 64 may also exist to activate the recirculation pump 40. The pump enable units 64 may consist of push buttons, switches, or another kind of interface that enables the activation of the recirculation pump 40. In the case of a single recirculation loop in the hot water network, there could be only one pump enable unit 64 that initiates recirculation, or there could be a pump enable unit 64 at each water usage location (e.g. near the faucet 19, etc.) where nearly instant hot water is desired.
In the case where multiple recirculation loops and bypass valves 60 are utilized, there would generally be a pump enable unit 64 at each water usage location. In addition to enabling the recirculation pump 40, the pump enable units 64, in conjunction with the bypass valves 60, may relay information to the control unit 30 indicating when to turn the recirculation pump 40 off, such as when the water in the recirculation loop has reached the desired temperature.
The pump enable units 64 may be hard wired to the control unit 30 or have remote capability. The pump enable units 64 may further be integrated with the bypass valves 60 and/or mounted separately at water usage locations. The pump enable units 64 may also have circuitry that communicates temperature information at the bypass valves 60 back to the control unit 30. The pump enable units 64 may control the recirculation pump 40 via communicating information to the control unit 30 or may directly control the recirculation pump 40. The pump enable units 64 may further control the bypass valves 60.
The pump enable units 64 may have various mounting features, such as adhesive material, fasteners, or the like. The pump enable units 64 also include a water resistant enclosure and include various programming features, such as shut-off temperature, remote control communication frequency and various others. The pump enable units 64 may further have a visual readout for viewing the water temperature in their respective bypass valve 60 or in the recirculation loop.
The present invention may include a check valve 50 positioned before the recirculation pump 40 in the flow of the cold water supply to the hot water heater 20. The check valve 50 is also positioned upstream of the point of interconnection of the recirculation line 17 and the cold water supply line 12. The purpose of the check valve 50 is to prevent water in the recirculation loop 17 from back flowing into the cold water supply 12.
The check valve 50 is constructed to allow the water to flow only in one direction. The check valve 50 may be comprised of various configurations, such as a ball and spring style where the ball rests in a pocket on one side of the valve and is held in that pocket on the other side by a compression spring. When water pushes against the ball from the pocket side of the valve, the ball moves out of the pocket and compresses the spring thus allowing water to flow through the valve. If water attempts to flow in the other direction, the spring extends and the ball seals itself inside the pocket preventing flow through the valve. Other types of check valves 50, such as a gate style, may be appreciated as well.
The present invention may also include bypass valves 60 connected between the cold and hot water supply lines 12, 14. The bypass valves 60 are further preferably located at the water usage locations, such as under a sink or faucet 19. The bypass valves 60 may further be located at several water usage locations, or alternatively, only used at the end of the hot water run to provide near instant hot water for the entire network of water lines and be mounted in various manners, such as but not limited to a wall or a pipe.
The bypass valves 60 are used when it is desired to recirculate the water throughout the system when heating the water. When the bypass line is activated or open, the hot water supply line 14 flows into the cold water line 12 creating a recirculation loop (i.e. second recirculation loop). When the water at the bypass valve 60 reaches a certain temperature, the recirculation pump 40 and bypass valve 60 are deactivated for nearly instant hot water at the faucet 19 or water usage location. This feature saves water by preventing the user from letting cold water flow down the drain while waiting for hot water.
The bypass valves 60 may be comprised of various types of two-way valves, such as but not limited to diaphragm type, ball valve variation, or gate valve variation. The bypass valves 60 may further have integrated temperature sensors within to signal the control unit 30 when to turn off the recirculation pump 40 once the water temperature reaches a certain threshold. The bypass valves 60 may also include buttons or controls to enable the recirculation pump 40. It is appreciated that the bypass valves 60 should only be used when the hot water network is not pre-plumbed for recirculation.
The bypass valve 60 may further be operated either electrically via a solenoid, etc. or manually. If powered electrically, the bypass valve 60 is generally plugged into an AC wall socket or powered via batteries. The bypass valve 60 may further be configured in various manners, such as but not limited to as a diaphragm style valve, a ball valve, a gate valve, or any other type of valve using a two-way application The bypass valve 60 may further have various types of functionality, such as to control the shut off temperature of the bypass valve 60, or the speed of the recirculation pump 40. Further, the bypass valve 60 may have an audible and/or visual alarm to notify the user when the water has reached the shut off temperature and when the recirculation pump 40 has turned off. It is appreciated that the bypass valve 60 may further be comprised of a passive configuration.
The bypass valve 60 forms the second recirculation loop for water within the water heater to flow during a second water heating process. The second recirculation loop formed by the bypass valve 60 covers a larger fluid area than the first recirculation loop. The second recirculation loop is also separate than the recirculation line 17 of the first recirculation loop. The second recirculation loop preferably includes the cold and hot water supply lines 12, 14, the water tank 21 and all parts in the flow thereof except the recirculation line 17. The first recirculation loop thus includes the water tank 21 of the hot water heater 20, the recirculation line 17 and the parts of the lines of the cold and hot supply lines 12, 14 interconnected therebetween.
As opposed to an electrically operated bypass valve 60, the other option is to have a temperature activated valve that closes on its own when the water flowing through it reaches a certain temperature. This valve will open back up when the water cools down. In line with the temperature activated valve could be a check valve to prevent flow in the opposite direction.
In conjunction with the temperature-activated valve 60, the recirculation pump 40 could have but is not limited to a paddle wheel flow meter or pressure transducer connected to it. When the temperature actuated bypass valve 60 closes, the flow meter would sense either that flow had stopped or the pressure transducer would register a spike in water pressure. A signal would then be sent to the system control unit 30 to turn the recirculation pump 40 off. The pump 40 will be turned on briefly in arbitrary intervals to see if the temperature activated bypass valve 60 is open. If the pressure spikes or the flow is zero that means the bypass valve 60 is closed and the pump 40 will immediately turn off. Otherwise the pump 40 will continue running until hot water reaches the temperature operated bypass valve 60 and causes it to close again.
If a temperature activated bypass valve is used instead of an electrically operated bypass valve, pump enable units 64 will not be necessary. The change in pressure of flow is what is used to monitor the state of the temperature activated bypass valve, and there is no need for user interaction.
There are a few advantages to using the temperature operated bypass valve. A first advantage is that the temperature activated bypass valve 60 is a passive device that does not require power or communication means with the system control unit 30. Another advantage is that because the temperature activated bypass valve 60 is a passive device it is easier to install and much cheaper to make than the electrically activated version. Another advantage is that because of the cost saving, the temperature bypass valve 60 makes the overall recirculation system 10 more economically viable.
The present invention may include multiple three-way valves 70, 72 to change from a first recirculation loop to a second recirculation loop, or back to an original flow setting. The three-way valves 70, 72 are generally only used when the hot water heater 20 includes a tank 21. Tankless water heaters do not need three-way valves since they only heat water when flow is initiated. The three-way valve can be comprised of multiple valve configurations, such as a ball valve, gate valve, diaphragm valve, electrically powered solenoid valves, or various others.
The three-way valve 70 generally includes an inlet, a first outlet, and a second outlet. The inlet is connected to the hot water supply line 14 coming from the water heater 20. The normally open first outlet is connected to the hot water network and the normally closed second outlet is connected to the quick reheat recirculation line 17, which is plumbed into the cold water supply line 12 going into the water heater 20 to form the first recirculation loop. When both three-way valves 70, 72 and the recirculation pump 40 are enabled, water recirculates through the water heater tank 21 via the second outlet causing the water to heat up quicker. When the hot water heater 20 is scheduled to begin reheating after a long period of inactivity, the three-way valves 70, 72 and the recirculation pump 40 are activated to create the first recirculation loop to heat the water in the tank 21 more quickly.
A variation of usage of the local recirculation loop is where the tank 21 includes two outlets 24 rather than one. The first outlet line is used to supply hot water to the water usage network, and the second outlet is used for the sole purpose of quickly reheating the tank 21. The second outlet may be tied into the cold water supply just upstream of the recirculation pump 40.
During normal operation, when hot water is being supplied to the water usage network, the bypass valve 60 is open and the three-way valves 70, 72 are closed. Then, when tank 21 regeneration is desired, the bypass valve 60 is closed and the three-way valves 70, 72 are open, thus allowing water to quickly recirculate through the tank 21 and heat up quickly.
During installation of the present invention, the system is installed in a pre-existing water heating setup or with a new water heating setup. The outlet 24 or hot water supply line 14 adjacent the outlet 24 of the water heater 20 first connects to the three-way valve 70. The normally open port of the three-way valve 70 then connects to the hot water supply line 14, which distributes hot water to each water usage location. The normally closed port of the three-way valve 70 is connected to the local recirculation line 17 for quick reheating which tees into the cold water supply line 12, via another three-way valve 72, upstream of the recirculation pump 40 and downstream of the cold water check valve 50.
If the pre-existing water heating system is plumbed for hot water recirculation, all hot water usage points are interconnected by a single pipe loop, which is tied into the cold water supply line 12, just upstream of the recirculation pump 40. It is appreciated that in place of the additional three-way valve 72, the check valve 50 may be used or any type of valve to prevent the water from the local recirculation line 17 from back flowing into the cold water supply line 12. The recirculation pump 40 can be placed near or far from the hot water heater 20 or may be an integral part of the hot water heater 20. The recirculation pump 40 is plumbed in line with the cold water supply line 12.
The pump enable units 64 may be placed at various locations, and are preferably located near the water usage points. The bypass valve 60, if not already connected, is connected preferably near the water usage point between hot water supply line 14 and the cold water supply line 12 to selectively form the second recirculation loop between the hot and cold water supply lines 12, 14. It is appreciated that the pump enable unit 64 may be integrated with the bypass valve 60. In alternative to the bypass valve 60, the end of the hot water supply line 14 may be connected to the water heater inlet 22 to form the second recirculation loop.
Once setup is complete, the control unit 30 is configured. The correct current time is ensured to be set upon the control unit 30. Then, the water-heating schedule may be specified. This is done by programming the times of day for which the water heater should be heating water. The same heating schedule can be set for each day of the week, or be unique for each day. The scheduling feature of the control unit 30 may also have features for setting vacation days where the water heater does not heat at all. The desired heating temperature may also be set with the control unit 30. The heating temperatures may include the desired temperature of the water within the tank 21, the recirculation shut-off temperatures, and the water temperature at the quick reheat points. Various other settings and synchronizations may also be set with the control unit 30.
The system is now ready for operation. At the start of the heating cycle, the three-way valve 70 on the hot water outlet 24 line toggles thus forming the first recirculation loop via fluidly connecting to the local recirculation line 17. The additional three-way valve 72 connected to the cold water supply line 12 upstream or the recirculation pump 40 also toggles. The recirculation pump 40 then turns on and recirculates water through the tank 21 causing the water to reach the desired set temperature much quicker. It is appreciated that the heating element 27 is turned on at this time. The heating element 27 may be set at a higher than normal level for even faster hot water regeneration. This reheat step could be automatically initiated later on in the heating cycle if the hot water in the tank 21 is depleted due to overuse. This reheat step is also referred to as the first heating process. If a tankless water heater is used, the local recirculation loop 17 will not be a part of the system 10.
Once the water is sensed to be at a desired temperature within the first recirculation loop, the control unit 30 changes modes to form a second recirculation loop and the first heating process ends and the second heating process begins. During the second heating process, the bypass valve 60 is opened connecting the hot water supply line 14 and the cold water supply line 12 at the water usage point and toggling the two three-way valves 70, 72 back to an initial position, thus cutting off the local recirculation line 17. The water then flows through the second recirculation loop to continue heating until the desired temperature has been reached via a sensor in the bypass valve 60, pump enabling unit 64, or other location.
Once the water is heated to a desired temperature, the control unit 30 signals the recirculation pump 40 to turn off and the bypass valve 60 toggles back to an initial position in which to connect the cold and hot water supply lines 12, 14 to their respective lines leading to the faucet 19. Now, when the user opens the hot water valve of the faucet 19, the user should receive nearly instant, hot water out of the faucet 19.
As time passes, and still within the heating schedule time, the water cools down, thus forcing the present invention back into heating the water. The recirculation pump 40 turns on and the bypass valve 60 toggles thus putting the water lines 12, 14 into the second recirculation loop. When the water is back at the desired temperature, the bypass valve 60 toggles back to an initial position to connect the water lines to the faucet 19. At the end of the heating schedule, the control unit 30 goes into an idle mode and the heating element 27 turns off to await the next preset heating schedule.
What has been described and illustrated herein is a preferred embodiment of the invention along with some of its variations. The terms, descriptions and figures used herein are set forth by way of illustration only and are not meant as limitations. Those skilled in the art will recognize that many variations are possible within the spirit and scope of the invention, which is intended to be defined by the following claims (and their equivalents) in which all terms are meant in their broadest reasonable sense unless otherwise indicated. Any headings, utilized within the description are for convenience only and have no legal or limiting effect.
I hereby claim benefit under Title 35, United States Code, Section 119(e) of U.S. provisional patent application Ser. No. 61/067,114 filed Feb. 27, 2008. The 61/067,114 application is currently pending. The 61/067,114 application is hereby incorporated by reference into this application.
| Number | Date | Country | |
|---|---|---|---|
| 61067114 | Feb 2008 | US |
