IL199687A - Heated water recirculation system - Google Patents

Description

HEATED WATER RECIRCULATION SYSTEM HEATED WATER RECIRCULATION SYSTEM FIELD OF THE INVENTION The invention relates to a water conservation system more particularly to a water saving system that is sufficiently flexible in design, to be conveniently installed in a variety of residential or commercial structures.

This invention relates particularly but not exclusively to a water conservation device for fitting to a domestic hot water line so as to divert water that is below a specified desired temperature away from the hot water line. The water is only directed to and through the hot water line once it reaches its desired temperature. The initial volume of water that is diverted can then be recovered and re-used. It will be convenient to hereinafter describe this invention with reference to this example application.

However, it is to be clearly understood that the invention HEATED WATER RECIRCULATION SYSTEM is capable of broader application. For example, the invention may be applied to a water system that provides cold water at a desired temperature, e.g. cold water for drinking. In this case the device will be used to divert an initial volume of water that is above the desired temperature away from a line and then recycle it back to a cooling device so that it can be re-used. Water will only be passed through the line when it is at or below a set temperature.

The primary requirement for the invention to find application is that the substance must be water and it must be desired for water to be supplied in a certain condition. Generally this condition will mean supplying water at a certain temperature. However, the applicant does not exclude diverting an initial volume of water until other conditions have been reached, for example, a certain concentration of components in the water, or a certain pH or salinity, or even a certain viscosity. The applicant envisages that the application of this invention could potentially be so wide that it is not possible at this time to provide a closed list of the possible uses of the invention.

BACKGROUND TO THE INVENTION In a domestic environment most building structures include a heated water supply system, regardless of whether the building is designed and/or used for industrial, commercial or residential purposes. It is a fact that heated water supply system that includes a water heater at a remote location from a water outlet apparatus results in a considerable amount of wasted water. When a person open a water outlet apparatus for the purpose of dispensing hot water, the water line between the water heater and the water outlet apparatus must first be purged of residual water, which may be at room temperature or ambient temperature depending on the routing of the water line. Once the residual water is purged from the water line between the water heater and the water outlet apparatus, heated water from the water heater will begin to be dispensed. This approach and need for first purging the water line of unheated water prior to receiving heated water from the water heater results in wasted water each time there is a need to dispensing hot water. In the worst case, the volume of water wasted each time there is a need to dispensing hot water, which is more than the volume of water held within the length of water line extending between the water heater and the water outlet apparatus.

Therefore, a heated water supply circuit that reduces or eliminates the wasting on unheated water prior to dispensing of heated water is useful.

Marcel Vataru, et al. in U.S. Pat. No. 4,160,461 Jul. 10, 1979 disclose a water and energy conservation system connectable between a hot water line and a hot water faucet. The system comprising a reservoir for saving clean water normally wasted as the hot water tap is turned on and the cold water retained in the hot water line between the hot water system and the faucet is drained. When the hot water faucet is turned on, the water in the hot water line is conducted into the reservoir where it accumulates until the water in the reservoir reaches a predetermined temperature. At this time, the reservoir is drained through the hot water faucet.

Lujan, Jr. et al. in U.S. Pat. No. 4,606,325 Aug. 19, 1986 disclose a water conservation system for use in residential dwellings or other buildings having a hot water distribution system. The system conserves water which is typically wasted by users while waiting for warm water to flow from a hot water faucet. The system provides a recirculation cooled hot water supply line from the cooled-off end of a hot water line back to the hot water heater of the hot water distribution system. The system is supplied with a plurality of control means to electrically energize the system's recirculation pump so long as a pressure switch detects that the main water supply is providing sufficient water pressure to the system.

Powers, Debora L. et al. in U.S. Pat No. 4,697,614 Oct. 6, 1987 describe the discharge ends of hot and cold water pipes, which are provided with valved outlets discharging into a common single water outlet and a by-pass pipe communicates the hot and cold water pipes upstream from but reasonably closely adjacent the hot and cold water outlets. A water accumulator is communicated with a mid-length portion of the bypass pipe, a remotely operable flow-control valve is serially connected in the by-pass pipe intermediate the accumulator and the hot water pipe and an adjustable pressure regulator is serially connected in the cold water pipe closely upstream from the by-pass pipe.

Barrett, John P. et al in U.S. Pat No. 4,870,986 Oct. 3, 1989 disclose a system for dispensing a liquid at a desired temperature from a hot liquid pressure line and a cold liquid pressure line to a plurality of liquid outlets such as a bathtub, a sink or the like. The system controls the temperature of the liquid flowing from the plurality of liquid outputs as well as controlling the level of liquid within a container and for maintaining the temperature of the liquid therein. The system includes a liquid recycling system which reduces the amount of liquid discarded during the operation of the system and to conserve heat energy. The system is controlled by a novel electronic control which when applied to a water dispensing system is able to control all functions of a bathtub as well as being capable of controlling a sink, a toilet or the complete water system for a residence, a hotel, an industrial or a medical complex or the like.

Haws, Spencer K. in U.S. Pat. No. 4,930,551 Jun. 26, 1990 discloses an automatic hot water recovery apparatus for recovering hot water from hot water lines extending to plumbing fixtures remotely disposed from the water heater. A flow regulator is provided for automatically adjusting the flow of water from the cold water line into the hot water line as a function of operating pressure within the plumbing system.

Hass, David N. in U.S. Pat. No. 5,050,062 September 1991 discloses a temperature controlled fluid system includes hot and cold fluid supply connections and hot and cold fluid valves for controlling the flow of the hot and cold fluids into the system. Each valve has a valve seat and a valve member which is moveable with respect to the valve seat. First and second stepper motors are connected to the valves in such a manner that actuation of the respective stepper motor moves the corresponding valve member in relationship to the associated valve seat. The system includes a mixer for promoting mixing of the hot and cold fluids into a fluid mixture which has a substantially uniform temperature throughout a given cross section of the mixed fluid flow. Also included in the system a device for generating an electrical signal corresponding to the actual temperature of the mixed fluid, and digital processing circuitry for computing an error value between the actual fluid temperature and a preselected value therefore and then applying a feedback control algorithm to the error value to generate a feedback control signal for the hot and cold fluid valves.

Britt, Paul E. in U.S. Pat. No. 5,105,846 Apr. 21, 1992 discloses a purge line to return cooled water in a hot water line directly to a cold water line to avoid wasting water by draining the cooled water while awaiting arrival of hot water at a hot water outlet valve. The purge line is connected in near adjacency to a hot water outlet valve to minimize the amount of cooled water still in the hot water line between the purge line and the valve.

Walsh, Paul E. in U.S. Pat. No. 5,261,443 Nov. 16, 1993 discloses a water saving recirculation system for a conventional water supply system wherein a fluid coupling and solenoid valve are disposed intermediate the hot water feed line and a first cold water feed line. A one way check valve is disposed in the cold water supply line and a pump disposed in the first cold water feed line for reversing the fluid flow through the first cold water feed line. The flow of water through the hot water feed line is diverted through the first cold water feed line until such time as the temperature of the water flowing through the hot water line reaches a predetermined valve.

Houlihan, John A. in U.S. Pat. No. 5,351,712 Oct. 4, 1994 and U.S. Pat. No. 5,775,372 Jul. 7, 1998 disclose a hot water recovery system is comprised of a dual chamber, dual hot water outlet, water heating reservoir and a flow control and recovery apparatus in fluid communication with a cold water supply and hot water outlets. The system is installed in new or existing structures, without alteration of the plumbing lines or electrical wiring. The flow is controlled upon command, drain standing water from the hot water outlets, and refills the outlets with hot water from the small chamber of the water heating reservoir, making hot water available at the instant an outlet is opened. During hot water use, the system delivers hot water to the hot water outlets from the large chamber, of the water heating reservoir. The system may be configured for use with any conventional water heater.

Lund William J. in U.S. Pat. No. 5,042,524 Aug. 27, 1991 and U.S. Pat. No 5,385,168 Feb. 14, 1995 discloses a hot water appliance with an accelerated delivery system which includes a pump interconnected between hot and cold water fittings and a control system for causing the pump to circulate water from the hot water fitting into the cold water fitting when the hot water appliance is turned on. Temperature sensor is provided for causing the control system to stop the pump to prevent heated water from being circulated into the cold water fitting. In addition, a hot water demand system may incorporate a sound sensor detecting water flow in a hot water delivery line and a sound-generating element may be provided for providing a characteristic sound in response to water flow in the hot water delivery line.

Bowman, Gerald E. in U.S. Pat. No. 5,452,740 Sep. 26, 1995 and continuation in part of U.S. Pat. No. 5,339,859 discloses a water conservation system including a thermostatically controlled valve means effectively diverts water from the hot water tank to a storage tank until the temperature or the water therefrom reaches a predetermined temperature. The stored water is then caused to be mixed with the water directed to the cold water conduit initially by pressure in the storage tank and subsequently by siphon action.

Price William D. in U.S. Pat. No. 5,511,579 April 1996 discloses a water conservation system that provides instant hot water at a user's sink. The system includes a backflow line positioned between the cold water line and a thermal switch. A check valve is placed in the backflow line to prevent hot water from entering the cold water supply. A thermal switch that contacts the flow of water is used to give a more accurate measurement of the hot water temperature. This system prevents large quantities of warm water from being pumped into the cold water supply.

Kempf, Dale in US Pat. No. 7,287, 707 describes a water control fixture having an operating valve and a thermostatically controlled bypass valve disposed in the fixture for bypassing water away from the fixture until the water temperature reaches a desired level. When pressurized water from the hot water heater reaches the desired temperature level at the fixture, the bypass valve closes and hot water is made available to the fixture. The bypass valve has a thermal actuator element that is thermally responsive to the temperature of the water. The fixture can have the housing with an interior chamber for operatively receiving the bypass valve. Various passages or channels can be provided to facilitate communication between the bypass valve and the water supply lines. Alternatively, the bypass valve can be positioned in the operating valve, including the moveable ball and the replaceable cylindrical valving cartridge types.

And Imhoff Ray et al. in U.S. Pat. No. 5,009,572 Apr. 23, 1991 describe a compact and self-contained circular water conservation device which can be easily installed in conjunction with existing and non-existing plumbing systems and fixtures having a source of pressurized water, a hot water supply line, a cold water supply line, a hot water heater, and outlet fixtures coupled to the hot and cold water supply lines. The water conservation device includes essentially an electric water pump for pumping water from the hot water supply line into a solenoid valve. The solenoid valve prevents the mixture of hot and cold water systems. The solenoid valve is coupled to the cold water line directly leading to and coupled to an outlet fixture. A thermostat temperature sensor is provided for detecting the hot water temperature at the inlet port of the pump. The water conservation device, when in operation, creates a closed loop linking the hot water line to the cold water line. The device moves the cooled hot water into the cold water line, causing immediate hot water to exit any hot water fixture outlet and, thus, conserving water in the process. The device does not require the hot water to be recalculated to the hot water heater. The device is easy to install by any homeowner and is small enough to fit inside a standard bathroom.

SUMMARY OF THE INVENTION The first embodiment of the heated water recirculation system for installing into existing plumbing systems and fixtures, in accordance with the present invention, has a source of pressurized water, a hot water supply line, a cold water supply line, a hot water heater, and outlet fixtures coupled to the hot and cold water supply lines.

My invention of the hot water recirculation does not include such complicated, expensive devices as: Flow-switches, Solenoids valves, Thermostats and Additional tube lines, used in the examiner inventions aforesaid. The device is easy to install into existing plumbing systems by any homeowner and is small enough to mount inside of fat. The invention does not require assembling additional electrical supply, devices, lines, transformers for flow- switches, solenoids valves, thermostats and inspections and control for them.

Using only electrical timer means with the predetermined time, which is necessary for recalculation cooled hot water to the hot water heater in fix time(sec) (method of determine of pump working is shown lower. ) and one- way valve in my invention instead of flow switch , solenoids valves, thermostats make this system more safe, reliable and cheap .

Predetermined time for circulate cooled hot water from the hot water source, supply line into cold water supply line and back to the hot water source determined (calculated) with the help of empirical formula: T= (18+3«n)« t"0 7 «10 τ - operation time of the pump ( sec) 18 the length of the tube in the room and on the roof (m) 3 the length of the tube between the stories (m) η number of stories from the flat to the roof t temperature of water in the tube or temperature of air outdoor °C 0. 7 - temperature coefficient which account a heat losses in the tubes . obtained empirically. correction coefficient taking into account time pump (sec) and water speed in the tubes.

Example: If the tenants are living on 2 floor of a 9-storey building (n - is equal to 7), the water temperature in winter 15 0 C duration pumping is equal 59 seconds, in the summer when water temperature is 27 0 C while the pump will be 39 seconds .

On this basis we can construct a table and use it in practice.

Timer means with predetermined time of circulation pump for circulate cooled hot water , one- way valve ,absence of additional water pipe lines and electrical lines is the general idea which make difference my invention from the similar ones.

The recirculation system comprising an electrically pump means, electrical timer means for fixing the duration of pump working , on/off power switch(push-button) , one- ay valve between a hot water supply line and cold water supply line and at least one means for utilizing cooled hot water. One- way valve function (turn on) automatically by water press from hot water supply line to cold water supply line only during pump working, for realize recirculation an unheated water in the hot water supply line to the hot water heater .

The electrically controlled pump means is disposed within the hot water supply lines for circulation water from the hot water supply line into the cold water supply line for hot water heater.

The manual on/off power switch serves for activating the electrical timer means with the predetermined time (sec) for working electrically controlled pump means and to circulate water from the hot water supply line through the one-way valve into the cold water supply line and back to a hot water source.

At least one means for utilizing cooled hot water has an inlet port, an outlet port and one or more an one- way valve. Number and disposition of one-way valve depend from the organization and structure of plumbing systems in apartment. This means is disposed near hot and cold water outlets within the plumbing system and interconnected by one- way valve between the hot and cold water supply lines for circulation of water from the hot water supply line into the cold water supply line.

The control means with a electrical timer means are provided for activating the electrically controlled pump means for the predetermined time and to circulate water from the hot water supply line into the cold water supply line and back to a hot water source.

The predetermined time for pump function depend from the length of the hot water supply line (distant from a hot water source to hot water plumbing outlet) and temperature of water in the tube or temperature of air outdoor and determined (calculated) with the help of empirical formula which show below. Or by practical way- with time measuring of delivering hot water from the hot water source to hot water plumbing outlet.

The electrically controlled pump means has an inlet port, connected to the hot water supply line and an outlet port, connected through the one- way valve to the cold water supply line for circulation of water from the hot water supply line into the cold water supply line for a hot water source.

At least one means for utilizing cooled hot water has an inlet port, and an outlet port. At least one means is disposed near hot and cold water outlets within the plumbing system and is connected with the hot and cold water supply lines by a first tee fitting with the gate adapted for valve coupling to the hot water supply line and , a second tee fitting with the gate adapted for valve coupling to the cold water supply line. At least one means is constructed as flexible tubing, which is connected with the hot and cold water supply lines by the first and second tee fittings , and the gates adapted for coupling to the hot and cold water supply lines.

Another embodiment of the present invention is a domestic plumbing system, having a source of pressurized water. The system comprising a cold water supply line, a hot water source, a hot water supply line, an electrically controlled pump means, electrical timer means, oneway valve, an on/off power switch and at least one means for utilizing cooled hot water.

The cold water supply line is connected with a source of pressurized water, a hot water source and at least one cold water plumbing outlet. The hot water supply line is connected between the hot water source and at least one hot water plumbing outlet.

The electrically controlled pump means is disposed within the plumbing system and interconnected between the hot and cold water supply lines through the one-way valve for circulation of water from the hot water supply line into the cold water supply line.

The manual on/off power switch is supplied for activating an electrical timer means with predetermined time and electrically controlled pump means to circulate water from the hot water supply line through the one- way valve into the cold water supply line and back to a hot water heater. The manual on/off power switch(push-button) may be disposed near the electrically controlled pump means or near at least one hot water outlet and at least one cold water outlet. For comfort it is possible to use remotely operated panel.

The system is supplied also at least one means for utilizing cooled hot water, having an inlet port, an one- way valve and an outlet port. This means is disposed near at least one hot water outlet and at least one cold water outlet within the plumbing system and is interconnected by an oneway valve between the hot and cold water supply lines for circulation of water from the hot water supply line into the cold water supply line. This means is connected with the hot and cold water supply lines by a first tee fitting ,valve with the gate adapted for coupling to the hot water supply line and a second tee fitting ,valve with the gate adapted for coupling to the cold water supply line. This means may be constructed as flexible tubing, which is connected with the hot and cold water supply lines by the first and second tee fittings valves and the gates adapted for coupling to these hot and cold water supply lines.

The domestic plumbing system further comprise a control means with the timer for activating the electrically controlled pump means for the predetermined time to circulate water from the hot water supply line into the cold water supply line and back to a hot water source. The control means may be supplied by remotely operated panel causing the control means to starting this electrically controlled pump means.

The electrically controlled pump means has an inlet port, connected to the hot water supply line and an outlet port with or without a one- way valve, connected to the cold water supply line and interconnected between the hot and cold water supply lines for circulation of water from the hot water supply line into the cold water supply line.

If the electrically controlled pump means is disposed outside or inside of the flat but within the flat plumbing system, it is supplied by one- way valve for preventing backflow there through when the pump means is stopped, and interconnected between these hot and cold water supply lines for circulation of water from the hot water supply line into the cold water supply line.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view of the water recirculation system according to the first embodiment of the invention, with all of component parts mounted as one unit; (variant of mounted :pump, timer and oneway valve in one unit 32) FIG. 2 is a schematic view of the water recirculation system according to the first embodiment of the invention, with means for utilizing cooled hot water and with the electrically controlled pump means, timer means mounted as one compact unit, one-way valves 60,62 mounted separately .

FIG. 3 is a schematic view of the electrically controlled pump means with the on/off switch, one-way valves 80 and timer means 32 in one unit according to the first embodiment of the invention; FIG. 4 is a schematic view of the water recirculation system with organize manifold, analogous to the second embodiment (without manifold)of the invention, with means for utilizing cooled hot water and with the electrically controlled pump means, timer means, mounted as one outside unit. One-way valves 60, 62 mounted separately .

FIG. 5 is a schematic view of the electrically controlled pump means with the on/off switch and timer means according to the second and the fourth embodiment of the invention.

FIG. 6 is a schematic view of connection of the existing plumbing system with the electrically controlled pump means, timer means, supplied by the on/off switch, control means and remotely operated panel.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawings and particularly to FIG. 1 and FIG. 2, there is shown the first embodiment of the heated water recirculation system for installing into existing plumbing systems 1. The heated water recirculation system as shown in FIG. 1, generally includes all component parts mounted in one unit 10, connected with hot water supply line 12, cold water supply line 14, coupled to source of pressurized water 16, hot water heater 18, and outlets 20 coupled to hot and cold water supply lines 12 and 14. Hot water heater 18 such as solar boiler with hot water tank 22 and solar water heating panel 24 as shown in the FIG. 1 connected to plumbing system 1 sink 26 outlets 20 by hot water supply line 12.

It is to be appreciated that hot water heater 18 may be solar boiler with hot water tank 22 and solar water heating panel 24, as shown in FIGS 1, 2, 4, or optionally a conventional electric capacity heater or a gas water heater (not shown in the drawings). Also provided in the conventional manner is cold water supply line 14 interconnecting sink 26 with cold water source of the pressurized water 16 which is also interconnected with hot water heater 18 via feeding line 28.

The heated water recirculation system shown in FIG 1 has all of component parts mounted as one unit 10 which is supplied with on/off power switch 30(place of mounted choose according comfort and safety precautions) and is supplied with timer means 32 and one-way valve 80 (FIG 3). Also on/off switch 30 may be mounted the same manner near another sink 34 with outlets 36 (FIG. 1). Unit 10 is connected with hot and cold water supply lines 12 and 14 by two plumber tees with gates 38, 40 and two flexible water lines 42, 44. It is to be understood that any variation in the diameter of the tees 38, 40, the thread size and type or shape of the plumber tees and water lines 42, 44 is within the scope of and intent of the invention.

Optional plumbing fixtures such as sinks 26, 34 and washing machine (not shown in the drawings) may be provided along with any other common plumbing fixture utilized in residences and businesses, all such fixtures being connected in a parallel configuration with hot water supply line 12 and cold water supply line 14 by feeding lines 46 and 48, 50 and 52. And the like feeding lines 54 and 56 serve for connecting shower 58 with hot water supply line 12 and cold water supply line 14.

At a selected plumbing fixture, such as the sink 26 which is most remote from hot water heater 18, electrically controlled pump means unit 10 is interconnected between hot water supply line 12 and cold water supply line 14 via feeding lines 46 and 48 respectively. Pump unit 10 (FIG1, FIG3)provides means for circulating water from hot water supply line 12 through one-way valve 80 (FIG 3) into cold water supply line 14 and back into hot water heater 18 via lines 44, 48, by utilizing the cold water supply line as a return feeder to hot water heater 18. No separate circulation line needs to be implemented in new systems. In order for pump unit 10 to effecting flow in a reverse manner through cold water supply line 14 and into hot water tank 22, pump unit 10 must, of course, develop sufficient water pressure and flow in the line. The control means with a electrical timer means 32 (FIGs3,4) are provided for activating the electrically controlled pump means for the predetermined time and to circulate water from the hot water supply line into the cold water supply line and back to a hot water source.

The heated water recirculation system shown in FIG 2 has all of component parts mounted as one compact unit 10, and shown in FIG5 which is remote from sinks 26, 34 and hot water heater 18.Unit 10 also supplied with on/off power switch 30 and with timer 32 FIG5 and serves for reversing cooled hot water through one-way valve 60,62 disposed under the sinks 26,34, to cold water supply line 14 and into hot water tank 22. The heated water recirculation system according to this variant of the first embodiment of the invention is supplied by one-way valve 60, 62 for utilizing cooled hot water, mounted near sinks 26, 34. Each one way valve 60, 62 for utilizing cooled hot water have an inlet port and an outlet port. This means is disposed near hot and cold water outlets 20 and 36 within plumbing system 1 and interconnected between hot and cold water supply lines 12 and 14 for circulation of water from hot water supply line 12 into cold water supply line 14.

Optionally, each one-way valve 60,62 for utilizing cooled hot water is connected with hot and cold water supply lines 12 and 14 by two plumber tees 87 with the taps 38,40 and two flexible water lines 44,42. (FIG2).It is to be understood that any variation in the diameter of the tees, the thread size and type or shape of the plumber tees and flexible water lines is within the scope of and intent of the invention.

The hot water recirculation system according to the first embodiment of the present invention (see FIG. 2) can be used in conjunction with existing plumbing system 1, which may include hot water heater 18, hot and cold water delivery lines 12, 14, and plumbing fixtures 20, 36. In this instance, unit 10 (see FIG. 3), which comprises electrically controlled pump means 64, on/off power switch 30 and control means 66 with timer means 32, may be installed in existing plumbing system 1. One-way valve 60,62 are mounted near hot and cold water outlets 20 and 36 separately from unit 10 .The advantages of this embodiment are significant in that no unwanted disruption of the housing or business structure is needed in order to implement the hot water recovery system in accordance with the present invention.

Pump means 64 with one way valve 80 according to the first embodiment of the invention (FIGS. 1, 3) is supplied with control means 66, may be of any common electrical type employing relays or solid state electronics, provides means for switching electrical current outlet 68 to pump means 64 in order to cause pump means 64 to circulate water from hot water line 12 and pump 64 inlet port 70 and outlet port 72 to cold water line 14.

Referring to FIG. 4, the second embodiment of the invention is included to show a heated water recirculation system to be constructed in new housing design. This system may be used also in existing homes; although the same as shown in the first embodiment in operation and result, the system related to the second embodiment no require more extensive plumbing and wiring work. The water conservation system related to the second embodiment is also designed so that a homeowner with common tools can install the system in their home for their own use.

The second embodiment according to FIG. 4 is shown as if installed in a typical home. Electrical pump means 64 is installed as one outside unit at hot water supply line 12 inlets in peripheral room or outside box 74. On/off power switch 30 is mounted near pump means 64 , near the sink or another place . Control means 66 with timer means 32 together with pump means 64, for switching electrical current outlet 68, hot water manifold 78, cold water manifold 76, are installed in peripheral room or box 74 on hot 12 water line. All wiring (not shown) from on/off power switch 30 may be routed through the house walls to the respective locations on pump means 64 so that the system operates as indicated in the first embodiment.

The domestic plumbing system according to the second embodiment of the invention (see FIGS. 4 - 6) has electrically controlled pump means 64 is disposed in peripheral room or box 74 as part of plumbing system 1 and interconnected between hot and cold water supply lines 12 and 14 through the one-way valve 60,62 for circulation of water from hot water supply line 12 into cold water supply line 28 and back to hot water tank 22 of hot water heater 18.

The electrically controlled pump means 64 (FIG. 4) has inlet port 82(FIG5), connected to hot water supply line 12 and outlet port 84, connected to hot water supply line 12 and interconnected between cold water supply lines 14 through one way valves 60,62 for utilizing cooled hot water. Electrically controlled pump means 64 is disposed within flat plumbing system 1 and it is supplied by one- way valves 60,62 for preventing backflow there through when pump means 64 is stopped, and interconnected between these hot and cold water supply lines 12 and 14 and (46-48,50-52)for circulation of water from hot water supply line 12 into cold water supply line 14.

Control means 32 (FIGS. 5, 6) is supplied with timer means 32 for activating electrically controlled pump means 64 for the predetermined time and to circulate water from hot water supply line 12 (FIG4) into cold water supply line 14 and back to hot water heater 18. Control means 66 may be supplied also by remotely operated panel 86 to starting or stopping this electrically controlled pump means 64.

Any variation in the location or design of referenced parts, types of lines and threads, and types of the pump, one-way valves or control means are within the scope of and intent of the invention. Any variation in the installation and materials, as long as the same purpose or objective is served, is within the scope of and intent of the invention.

The heated water recirculation system according to the present invention operates as follows.

The unit 10 power cord is plugged into electrical current outlet 68 (see FIG. l,). All of water plumbing fixtures 20 or 36 are closed. On/off switch (push-button) is placed in "on" position. Timer means 32 as shown in FIGS. 1, 2 and 4 is set to a desired time. Hot water line 12 temperature at plumbing fixtures 20 or 36 inlets is lower than it is needed, on/off switch(push-button) 30 will switch power on through its normally open contacts to energize electrically controlled pump means 64. At this point hot water from tee 88 with gate 38 is guided through flexible water lines 42 inlet to pump means 64 inlet 70 (FIG3) one-way valve80, outlet 72 ,flexible water lines 44 to cold water line at tee 87with gate 40. This water is guided into and through cold water line 14. The circulation of water continues through the closed loop created by the opening of pump means 64, one-way valve80, flexible water lines 42, 44 until the selected time on timer means 32 is over. After this time control means 66 with timer means 32 cutting off electrical power to pump means 64 and to reenergize the last. Any methods, that will inform the user that the selected water temperature has been achieved, may be utilized and is within the scope of and intent of the invention.

Referring to FIG. 2,4 water plumbing fixtures 20 or 36 is closed, on/off switch(push-button) 30 is placed in "on" position. Timer means 32 as it is shown in FIG. 2 is set to a desired time. Hot water line 12 temperature at plumbing fixtures 20 or 36 inlets is lower than it is needed, on/off switch(push-button) 30 will switch power on through timer means 32 and its normally open contacts to energize electrically controlled pump means 64. The water pressure in hot water line 12 increases and one-way valve of corresponding means for utilizing cooled hot water 60 or 62 opens. At this point hot water from line 12 though pump 64,hot water manifold 78 is guided into and through hot water lines 50,46, one-way valves 60,62 into and through cold water line 48,52 to cold water manifold 76, cold water line 28 and back to hot water tank 22 of hot water heater 18.

The circulation of water continues through the closed loop created by the opening of pump means 64 until the selected time on timer means 32 is over. After this time control means 66 cuts off electrical power to pump means 64 and to reenergize the last one. Any methods, that will inform the user that the selected water temperature has been achieved, may be utilized and is within the scope of and intent of the invention.

Referring to FIG. 4, the second embodiment of the invention is included to show a water recirculation system to be constructed in new housing design. This system may be used in existing homes although the same as the system according to the first embodiment in operation and result. The system related to the second embodiment will not require more extensive plumbing and wiring work. The water recirculation system related to the second embodiment is also designed so that a homeowner with common tools can install the system in their home for their own use.

Referring to FIG. 4, if one of water plumbing fixtures 20 or 36 is closed, switch(push-button)30 on/off and/or remotely operated panel 86 (Fig 6) is placed in "on" position causing control means 66 for placing in "on" position. Timer means 32 is set to a desired time. Hot water line 12 temperature at plumbing fixtures 20 or 36 inlets is lower than it is needed, on/off switch 30 or control means with timer means 32 will switch power on through its normally open contacts to energize electrically controlled pump means 64. The water pressure in hot water line 12 increases and one-way valve of corresponding means for utilizing cooled hot water 60 or 62 opens. At this point hot water from line 12 is guided into and through the pump 64, hot water manifold 78,hot water lines 50,46, one-way valve60,62 cold water line 48,52 cold water manifold 76, line 28 and back to hot water tank 22 of hot water heater 18. The circulation of water continues through the closed loop created by the opening of pump means 64 until the selected time on timer 32 is over. After this time control means 66 with timer 32 cuts off electrical power to pump means 64 and to reenergize the last one. Any methods, that will inform the user that the selected water temperature has been achieved, may be utilized and is within the scope of and intent of the invention.

The present invention is directed to water economy. In an average household, approximately 50 - 60 liter of water are wasted each day when the hot water outlets are turned on either at the sink, tub or shower waiting for the water to reach a desired temperature. It means that in each flat it is throws away to the sewerage up to 15 - 25 cubic meter of drinking water per year.

Although there has been hereinabove described a particular arrangement of a hot water recirculation system in accordance with the present invention, for the purpose of illustrating the manner in which the invention may be used to advantage, it should be appreciated that the invention is not limited thereto. Accordingly, any and all modifications, variations, or equivalent arrangements which may occur to those skilled in the art, should be considered to be within the scope of the present invention as defined in the appended claims.

ABSTRACT The invention relates particularly but not exclusively to a water conservation system for fitting to a domestic hot water line so as to divert water that is below a specified desired temperature away from the hot water line. The water is only directed to and through the hot water line once it reaches its desired temperature. The initial volume of water that is diverted can then be recovered and re-used. The system may be conveniently installed in a variety of residential or commercial structures. The system comprises the electrically controlled pump means with manual on/off power switch (push-button), timer means , one-way valve and at least one means for utilizing cooled hot water are disposed within the plumbing system and interconnected between the hot and cold water supply lines at a point remote from hot water source for circulation of water from the hot water supply line into the cold water supply line and back to a hot water source. The system may be additionally supplied with the control means and remotely operated panel. 33

Claims (12)

CLAIMS 199687/3 What is claimed is:

1. A heated water recirculation .system for installing into existing plumbing systems and fixtures having a source of pressurized water, a hot water supply line, a cold water supply line, a hot water heater, and outlet fixtures coupled to the hot and cold water supply lines, said recirculation system comprising: - an electrically controlled pump means, disposed within said plumbing system and interconnected between said hot and cold water supply lines for circulation of water from the hot water supply line into the cold water supply line, an on/off power switch (push-button) , timer means for predetermined work time and activating said electrically controlled pump means and to circulate water from the hot water supply line into the cold water supply line and back to a hot water source, and - at least one means for utilizing cooled hot water, having an inlet port, a one- way valve and an outlet port, said means is disposed near hot and cold water outlets within said plumbing system and interconnected between said hot and cold water supply lines for circulation of water from the hot water supply line into the cold water supply line; the predetermined time for pump function depend from the length of the hot water supply line (distant from a hot water source to hot water plumbing outlet) and temperature of water in the tube or temperature of air outdoor and determined (calculated) with the help of empirical formula which show below: predetermined time for circulate cooled hot water from the hot water source, supply line into cold water supply line and back to the hot water source determined (calculated) with the help of empirical formula: Τ= (18+3·η)· ί 0 7 ·10 T - operation time of the pump ( sec) 18 - the length of the tube in the room and on the roof (m) 3 - the length of the tube between the stories (m) n - number of stories from the flat to the roof t - temperature °c of water in the tube or temperature of air outdoor 26 0. 7 - temperature coefficient which account a heat losses in the tubes obtained empirically; 10 - correction coefficient taking into account time pump (sec) and water speed in the tubes. example: If the tenants are living on 2 floor of a 9-storey building (n - is equal to 7), the water temperature in winter 15 0 C duration pumping is equal 59 seconds, in the summer when water temperature is 27 0 C while the pump will be 39 seconds . this basis we can construct a table and use it in practice: 27 or by practical way: time measuring of delivering hot water from the hot water source to hot water plumbing outlet in the flat,

2. A heated water recirculation system according to claim 1, wherein said electrically controlled pump means has an inlet port, connected to said hot water supply line and an outlet port with a one- way valve, connected to said cold water supply line and interconnected between said hot and cold water supply lines for circulation of water from the hot water supply line into the cold water supply line?

3. A heated water recirculation system according to claim 1, wherein said at least one means for utilizing cooled hot water, having an inlet port, a one way valve and an outlet port, is disposed near hot and cold water outlets within said plumbing system and is connected with said hot and cold water supply lines by a first tee fitting with a gate adapted for coupling to said hot water supply line and a second tee fitting with a gate adapted for coupling to said cold water supply line.

4. A heated water recirculation system according to claim 4, wherein said at least one means for utilizing cooled hot water, having an inlet port, a one way valve and an outlet port lines are constructed as a flexible tubing, which is connected with said hot and cold water supply lines by a first and second tee fittings and the gates adapted for coupling to said hot and cold water supply lines. 28

5. A domestic plumbing system, having a source of pressurized water and comprising: - a cold water supply line connected with a source of pressurized water and at least one cold water plumbing outlet; - a hot water source, connected with said cold water supply line; - a hot water supply line connected between said hot water source and at least one hot water plumbing outlet; - an electrically controlled pump means, disposed within said plumbing system and interconnected between said hot and cold water supply lines for circulation of water from the hot water supply line into the cold water supply line; - an on/off power switch for activating said electrically controlled pump means for predetermined work time to circulate water from the hot water supply line into the cold water supply line and back to a hot water source; - and at least one means for utilizing cooled hot water, having an inlet port, a one way valve and an outlet port, said means is disposed near said at least one hot water outlet and at least one cold water outlet within said plumbing system and interconnected between said hot and cold water supply lines for circulation of water from the hot water supply line into the cold water supply line; predetermined time for circulate cooled hot water from the hot water source, supply line into cold water supply line and back to the hot water source determined (calculated) with the help of empirical formula: 29 Τ= (18+3·η)· f" ' ·10 Τ - operation time of the pump ( sec) 18 - the length of the tube in the room and on the roof (m) 3 the length of the tube between the stories (m) η number of stories from the flat to the roof t temperature °c of water in the tube or temperature of air outdoor 0. 7 - temperature coefficient which account a heat losses in the tubes obtained empirically; 10 correction coefficient taking into account time pump (sec) and water speed in the tubes; on this basis we can construct a table and use it in practice, which shown earlier;

6. The domestic plumbing system according to claim 6, which further comprises control means with a timer for activating said electrically controlled pump means for the predetermined time to circulate water from the hot water supply line into the cold water supply line and back to a hot water source.

7. The domestic plumbing system according to claim 7, wherein said control means with a timer for activating said electrically controlled pump means is supplied by remotely operated panel causing the control means to starting or stopping said electrically controlled pump means. 30

8. The domestic plumbing system according to claim 6, wherein said on/off power switch (push-button)is disposed near said electrically controlled pump means and (or) near at least one hot water outlet and (or) at least one cold water outlet.

9. The domestic plumbing system according to claim 6, wherein said electrically controlled pump means has an inlet port, connected to said hot water supply line and an outlet port with a one way valve, connected to said cold water supply line and interconnected between said hot and cold water supply lines for circulation of water from the hot water supply line into the cold water supply line.

10. The domestic plumbing system according to claim 6, wherein said at least one means for utilizing cooled hot water, having an inlet port, a one way valve and an outlet port, which is disposed near hot and cold water outlets within said plumbing system, is connected with said hot and cold water supply lines by a first tee fitting with a gate adapted for coupling to said hot water supply line and a second tee fitting with a gate adapted for coupling to said cold water supply line.

11. The domestic plumbing system according to claim 11, wherein said at least one means for utilizing cooled hot water, having an inlet port, a one way valve and an outlet port lines is constructed as a flexible tubing, which is connected with said hot and cold water supply lines by a first and second tee fittings and the gates adapted for coupling to said hot and cold water supply lines. 31

12. The domestic plumbing system according to claim 6, wherein said electrically controlled pump means, is disposed outside of the flat, but within said flat plumbing system, is supplied by its own one way valve for preventing backflow there through when the pump means is stopped, and interconnected between said hot and cold water supply lines for circulation of water from the hot water supply line into the cold water supply line. Inventor: Leonid Bukhman 32