U.S. patent application number 11/651778 was filed with the patent office on 2007-07-26 for system and method for producing on demand high temperature water.
This patent application is currently assigned to McIllwain Equipment Company, Inc.. Invention is credited to Jim McIllwain.
Application Number | 20070170273 11/651778 |
Document ID | / |
Family ID | 38284570 |
Filed Date | 2007-07-26 |
United States Patent
Application |
20070170273 |
Kind Code |
A1 |
McIllwain; Jim |
July 26, 2007 |
System and method for producing on demand high temperature
water
Abstract
A system and method for efficiently producing high flow rate
on-demand hot water. The system utilizes on-demand hot water
heaters, super heated water expansion tanks, and a high flow mixing
valve.
Inventors: |
McIllwain; Jim; (Argyle,
TX) |
Correspondence
Address: |
T. Ling Chwang;Suite 6000
901 Main Street
Dallas
TX
75202
US
|
Assignee: |
McIllwain Equipment Company,
Inc.
Argyle
TX
|
Family ID: |
38284570 |
Appl. No.: |
11/651778 |
Filed: |
January 10, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60757713 |
Jan 10, 2006 |
|
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|
Current U.S.
Class: |
237/19 |
Current CPC
Class: |
F24D 17/00 20130101;
F24D 19/1063 20130101 |
Class at
Publication: |
237/019 |
International
Class: |
F24D 3/08 20060101
F24D003/08 |
Claims
1. A water heating system comprising: (a) a water inlet conduit for
supplying water from an external source; (b) a first valve having
an inlet and an outlet, wherein the inlet of the first valve is in
fluid communication with the water inlet conduit, and the outlet of
the first valve is in fluid communication with a water conduit
having a bifurcation with at least a first and a second bifurcated
path; (c) a second valve having an inlet and an outlet, wherein the
inlet of the second valve is in fluid communication with the outlet
of the first valve through the first bifurcated path of the water
conduit; (d) a mixing valve having a first inlet, a second inlet,
and an outlet, wherein the first inlet of the mixing valve is in
fluid communication with the outlet of the second valve; (e) a hot
water heater having an inlet port and an outlet port, wherein the
inlet port of the hot water heater is in fluid communication with
the second bifurcated path of the water conduit; (f) a hot water
expansion tank in fluid communication with the hot water heater;
(g) a third valve having an inlet and an outlet, wherein the hot
water heater and the hot water expansion tank are in fluid
communication with the inlet of the third valve, and the outlet of
the third valve is in fluid communication with the second inlet of
the mixing valve; and (h) a hot water conduit in fluid
communication with the outlet of the mixing valve.
2. A process for producing hot water using the water heating system
of claim 1 comprising: (a) allowing the water from an external
source to flow into the water inlet conduit, subsequently flowing
through the inlet of the first valve, followed by flowing through
the outlet of the first valve, and then flowing through the water
conduit reaching the first and the second bifurcated paths of the
water conduit; (b) allowing a first portion of the water reaching
the water conduit to flow through the first bifurcated path of the
water conduit, then through the inlet of the second valve,
subsequently through the outlet of the second valve, and then
through the first inlet of the mixing valve; (c) allowing a second
portion of the water reaching the water conduit to flow through the
second bifurcated path of the water conduit, then through the inlet
port of the hot water heater, subsequently through the outlet port
of the hot water heater, then through the inlet of the third valve,
subsequently through the outlet of the third valve, and then
through the second inlet of the mixing valve; (d) allowing water
from the first inlet of the mixing valve to combine with water from
the second inlet of the mixing valve to give a heated water; and
(e) allowing the heated water to flow through the outlet of the
mixing valve to the hot water conduit.
3. The water heating system of claim 1, wherein the water conduit
is in fluid contact with a pop-off safety valve or an expansion
tank.
4. The water heating system of claim 1, wherein the hot water
heater is in fluid communication with a pop-off safety valve or an
expansion tank.
5. The water heating system of claim 1, wherein the hot water
heater inlet port or outlet port comprises a ball valve.
6. The water heating system of claim 1, wherein the hot water
conduit is in fluid communication with a thermometer or temperature
safety device.
7. A water heating system comprising: (a) a water inlet conduit for
supplying water from an external source; (b) a first valve having
an inlet and an outlet, wherein the inlet of the first valve is in
fluid communication with the water inlet conduit, and the outlet of
the first valve is in fluid communication with a water conduit
having a bifurcation with at least a first and a second bifurcated
path; (c) a second valve having an inlet and an outlet, wherein the
inlet of the second valve is in fluid communication with the outlet
of the first valve through the first bifurcated path of the water
conduit; (d) a mixing valve having a first inlet, a second inlet,
and an outlet, wherein the first inlet of the mixing valve is in
fluid communication with the outlet of the second valve; (e) one or
more hot water heaters, each having an inlet port and an outlet
port, wherein the inlet port of each hot water heater is in fluid
communication with the second bifurcated path of the water conduit;
(f) one or more hot water expansion tanks in fluid communication
with one or both of the hot water heaters; (g) a third valve having
an inlet and an outlet, wherein each of the hot water heaters and
each of the hot water expansion tanks are in fluid communication
with the inlet of the third valve, and the outlet of the third
valve is in fluid communication with the second inlet to the mixing
valve; and (h) a hot water conduit in fluid communication with the
outlet of the mixing valve.
8. A process for producing hot water using the water heating system
of claim 7 comprising: (a) allowing the water from an external
source to flow into the water inlet conduit, subsequently flowing
through the inlet of the first valve, followed by flowing through
the outlet of the first valve, and then flowing through the water
conduit reaching the first and the second bifurcated paths of the
water conduit; (b) allowing a first portion of the water reaching
the water conduit to flow through the first bifurcated path of the
water conduit, then through the inlet of the second valve,
subsequently through the outlet of the second valve, and then
through the first inlet of the mixing valve; (c) allowing a second
portion of the water reaching the water conduit to flow through the
second bifurcated path of the water conduit, then through the inlet
port of one or more of the hot water heaters, subsequently through
the outlet port of one or more of the hot water heaters, then
through the inlet of the third valve, subsequently through the
outlet of the third valve, and then through the second inlet of the
mixing valve; (d) allowing water from the first inlet of the mixing
valve to combine with water from the second inlet of the mixing
valve to give a heated water; and (e) allowing the heated water to
flow through the outlet of the mixing valve to the hot water
conduit.
9. The water heating system of claim 7, wherein the water conduit
is in fluid communication with a pop-off safety valve or an
expansion tank.
10. The water heating system of claim 7, wherein one or more of the
hot water heaters is in fluid contact with a pop-off safety valve
or an expansion tank.
11. The water heating system of claim 7, wherein one or more of the
hot water heater inlet ports or hot water heater outlet ports
comprises a ball valve.
12. The water heating system of claim 7, wherein the hot water
conduit is in fluid communication with a thermometer or temperature
safety device.
13. A water heating system comprising: (a) a water inlet conduit
for supplying water from an external source; (b) a first valve
having an inlet and an outlet, wherein the inlet of the first valve
is in fluid communication with the water inlet conduit, and the
outlet of the first valve is in fluid communication with a water
conduit having a bifurcation with at least a first and a second
bifurcated path; (c) a second valve having an inlet and an outlet,
wherein the inlet of the second valve is in fluid communication
with the outlet of the first valve through the first bifurcated
path of the water conduit; (d) a mixing valve having a first inlet,
a second inlet, and an outlet, wherein the first inlet of the
mixing valve is in fluid communication with the outlet of the
second valve; (e) one or more hot water heaters, each having an
inlet port in fluid communication with the second bifurcated path
of the water conduit; (f) one or more hot water expansion tanks in
fluid communication with one or both of the hot water heaters; (g)
a third valve having an inlet and an outlet, wherein the third
valve inlet is in fluid communication with each of the hot water
heaters and each of the hot water expansion tanks, and the third
valve outlet is in fluid communication with the second inlet to the
mixing valve; (h) a discharged water conduit in fluid communication
with the outlet of the mixing valve; (i) a storage tank having an
inlet, a first outlet, and a second outlet, wherein the storage
tank inlet is in fluid communication with the discharged water
conduit; (j) a fourth valve having an inlet and an outlet, wherein
the inlet of the fourth valve is in fluid communication with the
first outlet of the storage tank and wherein the outlet of the
fourth valve is in fluid communication with a recirculation
conduit; (k) a recirculation pump having an inlet and an outlet,
wherein the inlet of the recirculation pump is in fluid
communication with the recirculation conduit and the outlet of the
recirculation pump is in fluid communication with one or both of
the hot water heaters; and (l) a fifth valve having an inlet and an
outlet wherein the inlet of the fifth valve is in fluid
communication with the second outlet of the storage tank and the
outlet of the fifth valve is in fluid communication with a hot
water conduit.
14. A process for producing hot water using the water heating
system of claim 13 comprising: (a) allowing the water from an
external source to flow into the water inlet conduit, subsequently
flowing through the inlet of the first valve, followed by flowing
through the outlet of the first valve, and then flowing through the
water conduit reaching the first and the second bifurcated paths of
the water conduit; (b) allowing a first portion of the water
reaching the water conduit to flow through the first bifurcated
path of the water conduit, then through the inlet of the second
valve, subsequently through the outlet of the second valve, and
then through the first inlet of the mixing valve; (c) allowing a
second portion of the water reaching the water conduit to flow
through the second bifurcated path of the water conduit, then
through the inlet port of one or more of the hot water heaters,
subsequently through the outlet port of one or more of the hot
water heaters, then through the inlet of the third valve,
subsequently through the outlet of the third valve, and then
through the second inlet of the mixing valve; (d) allowing water
from the first inlet of the mixing valve to combine with the water
from the second inlet of the mixing valve to give a heated water;
(e) allowing the heated water to flow through the outlet of the
mixing valve to the discharged water conduit, then through the
inlet of the storage tank to reach the storage tank; (f) allowing a
first portion of the water reaching the storage tank to flow
through the inlet of the fourth valve, subsequently through the
outlet of the fourth valve, then through the recirculation conduit,
then through the inlet of the recirculation pump, subsequently
through the outlet of the recirculation pump, then through the
inlet port of one or more of the hot water heaters; and (g)
allowing a second portion of the water reaching the storage tank to
flow through the second outlet of the storage tank, then through
the outlet of the fifth valve, subsequently through the hot water
conduit.
15. The water heating system of claim 13, wherein the water conduit
is in fluid communication with a pop-off safety valve or an
expansion tank.
16. The water heating system of claim 13, wherein one or more of
the hot water heaters is in fluid communication with a pop-off
safety valve or an expansion tank.
17. The water heating system of claim 13, wherein the discharged
water conduit is in fluid communication with a thermometer or a
temperature safety device.
18. The water heating system of claim 13, wherein the hot water
conduit is in fluid communication with a thermometer or a
temperature safety device.
19. The water heating system of claim 13, wherein the storage tank
is in fluid communication with a thermometer or a temperature
safety device.
20. The water heating system of claim 13, wherein the storage tank
is in fluid communication with a pressure safety device.
Description
[0001] This application claims priority to U.S. Provisional Patent
Application Ser. No. 60/757,713, entitled "SYSTEM AND METHOD FOR
PRODUCING ON DEMAND HIGH TEMPERATURE WATER" filed on Jan. 10, 2006,
having Jim McIllwain and Helen McIllwain, listed as the inventors,
the entire content of which is hereby incorporated by
reference.
BACKGROUND
[0002] The invention is generally related to a water heater system
and method of operating the water heater system. More specifically,
the invention relates to an energy efficient water heater system
for commercial or domestic use that can produce a large scale
amount of high temperature water on demand. The water heater system
of this invention has a more energy efficient recovery rate than
conventional large scale hot water heaters.
[0003] Hotels, apartment complexes, restaurants, laundromats, and
other commercial business typically utilize large quantities of hot
water throughout the business day. However, the demand for hot
water varies greatly with different times of the day and with
different seasons of the year. The availability of hot water can
have direct consequences to the business owners. For example,
hotels and apartment buildings may experience a large demand for
hot water in the morning when most patrons are taking showers
simultaneously, however, the same hotel or apartment may not
experience a great demand for hot water the rest of the day.
Restaurants may have a high demand for hot water to wash dishes
during the breakfast, lunch, or dinner rush, but not during the
rest of the day. Laundromats may have a higher demand for hot water
on the weekends compared to the weekdays.
[0004] The amount of energy that it takes to heat and maintain the
temperature of enough hot water to meet the demand during peak
hours can be considerable. However, the cost of customers not
returning to a business because they were inconvenienced by the
lack of hot water is considerably higher. Many businesses choose to
purchase large scale water heaters to maintain a sufficient hot
water supply for the time of day when the demand for hot water is
high.
[0005] The Conventional Water Heaters. Generally, conventional
water heaters and boilers include a steel tank, insulated by foam
encased in a metal jacket. Cold water runs into the steel tank. The
cold water can be heated by electrical heating elements or gas with
heat exchangers to a predetermined temperature (i.e. 120.degree.
F.), which is maintained until the hot water is used. Maintaining
the temperature of hot water in the tank can be energy inefficient
during non-peak times. To utilize the hot water, a user can open a
faucet and hot water exits the steel tank through a pipe connected
to the faucet. While hot water is drained from the pipe, cold water
mixes with the remaining hot water, which reduces the temperature
of the remaining water. Reducing the temperature of the water in
the tank is especially inefficient during times of peak demand for
hot water. During hot water usage, the temperature of the remaining
water is lower than the predetermined temperature, which activates
the heating device to maintain the water at the pre-determined
temperature. The amount of time it takes to reheat a specified
number of gallons of water to the predetermined temperature is
considered the recovery rate, and is generally measured in
gallons/hour. Thus, in order to maintain enough hot water to meet
any demand, the tank size can be increased or the predetermined
temperature can be increased. Both options are inefficient during
non-peak hours. Thus, conventional water heaters have many
drawbacks including inefficient heating, easy loss of heat energy,
low recovery rates, and high installation space requirements.
[0006] The average temperature of tap water varies throughout any
given state, depending upon the location, elevation, and time of
year. For the purposes of these examples, a tap water temperature
of 70.degree. Fahrenheit will be used. Therefore, to achieve a
temperature of about 160.degree. Fahrenheit at the faucet, the
required rise would be about 90.degree..
[0007] For example, one commercially available water heater from
Kenmore (Dallas, Tex.) is called the "Kenmore 98 Gallon Natural Gas
Commercial Water Heater." The Kenmore water heater offers a 98
gallon tank capacity has an hourly input of about 75,000 BTU, and a
recovery rate, at about a 90.degree. F. degree rise, of 78.8
gallons per hour (GPH). Thus, in order to insure a recovery rate of
about 800 gallons per hour, one would need about 10 of similar
water heaters, using about 800,000 BTU/hour, which does not include
the amount of energy required to keep the water at the
predetermined temperature for non-peak hours.
[0008] On Demand Heaters. In order to decrease the amount of energy
that is required to heat and maintain the temperature of hot water
during high demand times, high efficiency on demand commercial
water heaters have been introduced. These heaters produce hot water
only when needed, so energy to maintain the hot water at a
predetermined temperature during non-peak hours is eliminated. For
example, one commercially available high efficiency water heater
from Rinnai Inc. (Nagoya, Japan) is called the "Continuum" model
2532FFU. The Continuum is a temperature controlled continuous flow
gas hot water heating system that offers a supply of hot water
through multiple outlets simultaneously. One Continuum unit has a
typical hot water capacity of about 8.5 gallons per minute ("GPM"),
which is enough to run about two showers and a third point of use
at the same time without any loss of temperature consistency. The
Continuum has a gas input of about 15,000 to about 180,000 BTU/hour
with efficiency up to about 87%.
[0009] It is also possible to increase the hot water capacity by
using multiple Continuum units. When multiple water heaters are
connected, they must be installed in parallel, not in series. The
capacity of single and multiple water heaters is shown in the table
below: TABLE-US-00001 Temp. Rise* 1 Unit 2 Units 3 Units 3 Units
(.degree. F.) GPM GPM GPM GPH 140.degree. F. 2.4 4.8 7.2 429.9
100.degree. F. 3.3 6.7 10.0 600.8 90.degree. F. 3.7 7.4 11.1 688.6
75.degree. F. 4.5 8.9 13.4 802.4 50.degree. F. 5.6 11.1 15.7 1003.0
25.degree. F. 8.5 15.9 25.4 1521.0 *The term "Rise" refers to the
temperature of water as it leaves the water heater minus the
temperature of the water entering the water heater.
[0010] Thus, in order to insure a recovery rate of about 800
gallons per hour, one would need about 3 of similar water heaters,
using about 550,000 BTU/hour.
[0011] One of the advantages of an instantaneous water heater is
its ability to provide a continuous supply of hot water. However,
since the water passes through a heat exchanger, the water must
flow through the unit slowly to ensure proper heat transfer.
[0012] Therefore, the quantity, or rate, at which the hot water is
delivered can be significantly less than that provided by a storage
water heater. When hot water is utilized at several locations of a
facility at the same time the flow of hot water to each fixture can
be severely restricted. As a result of the restricted output of
instantaneous water heaters, more than one unit may be required,
depending on the numbers and types of sinks and equipment present.
Due to the flow limitations inherent in the design of instantaneous
water heaters, some local health agencies may restrict or prohibit
their usage in businesses such as restaurants.
[0013] One embodiment of the invention described herein is a hot
water mixing system that utilizes at least one hot water heater,
such as a standard hot water heater or an on demand hot water
heater, one or more superheated water expansion tanks, and one or
more super high flow mixing valve to deliver a high flow of hot
water having about a 90.degree. F. rise, and a recovery rate of
between about 400 gallons and 800 gallons per hour using only about
199,000 BTU.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The following drawings form part of the present
specification and are included to further demonstrate certain
aspects of the present invention. The invention may be better
understood by reference to one or more of these drawings in
combination with the detailed description of specific embodiments
presented herein.
[0015] FIG. 1 shows a diagram of a system for producing demand
temperature hot water using a mixing device with at least one water
heater.
[0016] FIG. 2 shows a diagram of a system for producing demand
temperature hot water using a mixing device with at least two water
heaters.
[0017] FIG. 3 shows a diagram of a system for producing demand
temperature hot water using a mixing device with one or more
storage tanks.
SUMMARY
[0018] The invention described herein comprises a hot water mixing
system that may utilize at least one water heater (such as a
tankless water heater, an on demand water heater, or a conventional
water heater) one superheated water expansion tank, and a super
high flow mixing valve to deliver a high flow of hot water having
about a 90.degree. F. rise, and a recovery rate of about 400
gallons per hour to about 800 gallons per hour using only about
199,000 BTU.
[0019] One aspect of the current invention is a water heating
system that utilizes a water inlet conduit for supplying water from
an external source. A first ball stop valve having an inlet and an
outlet, and the inlet is in fluid communication with the water
conduit supplying cold water to the system. The outlet is connected
to a conduit having a bifurcation. One path of the bifurcation
leads to a second ball stop valve, a check valve and a first inlet
of a high flow mixing device. The second path of the bifurcation is
connected to at least one hot water heater. The cold water entering
the hot water heater becomes super heated and exits the heater to
flow into an expansion tanks and through a hot water conduit
system, which also leads to a second inlet of the mixing device.
The mixing device will mix superheated water from the heater and
cold water to expel hot water that is at a predetermined
temperature. The water heating system combines a water heater or
water heaters, such as a standard hot water heater or an on demand
hot water heater, expansion tanks and mixing valve for energy
efficient and high flow rate alternative to conventional hot water
heaters.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0020] Terms: It will be readily apparent to one skilled in the art
that various substitutions and modifications may be made in the
invention disclosed herein without departing from the scope and
spirit of the invention.
[0021] The term "a" or "an" as used herein in the specification may
mean one or more. As used herein in the claim(s), when used in
conjunction with the word "comprising", the words "a" or "an" may
mean one or more than one. As used herein "another" may mean at
least a second or more.
[0022] The term "Booster Heater" as used herein refers to an
instantaneous water heater designed and intended to raise the
temperature of hot water to a higher temperature for a specific
purpose, such as for the sanitizing rinse on a high temperature
automatic dish machine and laundromat machines.
[0023] The term "British Thermal Unit" ("BTU") as used herein
refers to the quantity of heat required to raise the temperature of
one pound of water one degree Fahrenheit.
[0024] The term "Gallons Per Hour" ("GPH") as used herein refers to
the amount of water, in gallons, that is used each hour by the
plumbing fixtures and equipment, such as dish machines and
laundromat machines.
[0025] The term "Gallons Per Minute" ("GPM") as used herein refers
to the amount of water, in gallons, flowing through a plumbing
fixture or through an instantaneous water heater per minute.
[0026] The term "Instantaneous Water Heater" as used herein refers
to a water heater that generates hot water on demand.
[0027] The term "Kilowatt" ("KW") as used herein refers to a unit
of electric power equal to 1,000 watts.
[0028] The term "Rise" as used herein refers to the temperature of
water as it leaves the water heater minus the temperature of the
water entering the water heater.
[0029] The term "Storage Water Heater" as used herein refers to a
water heater that incorporates a thermostat, a storage tank, and a
burner or heating elements, to heat and maintain the water within
the tank at a specific temperature.
[0030] The term "Super Heated Water Storage Tank" as used herein
refers to a storage tank that receives superheated water for a
period of time during peak hot water demand.
[0031] The term "Thermal Efficiency" as used herein refers to the
measure of the overall efficiency of the water heater, taking Water
Heater Guidelines into consideration loss of energy due to
combustion, radiation, convection and conduction of heat from the
unit.
[0032] The term "Water Heater" or "Hot Water Heater" as used herein
may refer to an on-demand water heater, a tankless water heater, a
standard water heater, or a number of other embodiments for heating
water to a desired temperature.
[0033] The term "Valve" as used herein may refer to a check valve,
a ball valve, a regulating flow valve, a tempering valve, a
pressure regulator valve, or a number of other types of valves for
regulating the flow of fluid.
[0034] A preferred embodiment of the invention comprises at least
one water heater and a mechanism for mixing heated water with cold
water from a water supply. Cold water may be introduced to the
system via a cold water supply conduit, which may contain one or
more valves for regulation of the flow of water. The cold water
flows through the cold water supply conduit to a bifurcation. One
bifurcated path may comprise one or more valves for regulation of
the flow of water and leads to a cold water supply inlet of a
mixing device, preferable a tempering mixing valve. The second
bifurcated path allows water to flow into a water heater,
preferably a conventional forced air downdraft heater or a tankless
water heater or an on demand water heater. The water heater and/or
the cold water supply conduit may have one or more safety valves,
and may be in connection with one or more expansion tanks. The
water heater is in fluid communication with a super heated water
supply inlet of the mixing device. Water from the cold water supply
inlet of the mixing device is mixed with water from the super
heated water supply inlet of the mixing device to discharge water
of the desired temperature.
[0035] A second preferred embodiment of the invention comprises at
least two water heaters connected in parallel and a mechanism for
mixing heated water with cold water from a water supply. Cold water
may be introduced to the system via a cold water supply conduit,
which may contain one or more valves for regulation of the flow of
water. The cold water flows through the cold water supply conduit
to a bifurcation. One bifurcated path may comprise one or more
valves for regulation of the flow of water and leads to a cold
water supply inlet of a mixing device, preferable a tempering
mixing valve. The second bifurcated path allows water to flow into
the two or more water heaters, preferably conventional forced air
downdraft heaters or tankless water heaters or on demand water
heaters. The water heaters and/or the cold water supply conduit may
have one or more safety valves, and may be in connection with one
or more expansion tanks. The water heaters are in fluid
communication with a super heated water supply inlet of the mixing
device. Water from the cold water supply inlet of the mixing device
is mixed with water from the super heated water supply inlet of the
mixing device to discharge water of the desired temperature.
[0036] A third preferred embodiment of the invention comprises at
least one water heater, a storage tank, and a mechanism for mixing
heated water with cold water from a water supply. Cold water may be
introduced to the system via a cold water supply conduit, which may
contain one or more valves for regulation of the flow of water. The
cold water flows through the cold water supply conduit to a
bifurcation. One bifurcated path may comprise one or more valves
for regulation of the flow of water and leads to a cold water
supply inlet of a mixing device, preferable a tempering mixing
valve. The second bifurcated path allows water to flow into one or
more water heaters, preferably a conventional forced air downdraft
heater or a tankless water heater or an on demand water heater. The
water heater and/or the cold water supply conduit may have one or
more safety valves, and may be in connection with one or more
expansion tanks. The water heater is in fluid communication with a
super heated water supply inlet of the mixing device. Water from
the cold water supply inlet of the mixing device is mixed with
water from the super heated water supply inlet of the mixing device
to discharge water of the desired temperature. The discharged water
flows through a conduit into a storage tank, preferably a tank with
a capacity of approximately 100-600 gallons. The storage tank may
be in contact with a thermometer and may comprise a pressure safety
device for monitoring or regulating the pressure of the storage
tank. The storage tank comprises a conduit for discharging water
when required for use. The storage tank further comprises a
circulation outlet, which allows water to move from the storage
tank back to the water heater. The flow of water from the storage
tank to the water heater is regulated by a circulating pump,
preferably with a capacity of between about 1 gallon/minute and
about 100 gallons/minute.
EXAMPLES
[0037] The following examples are provided to further illustrate
this invention and the manner in which it may be carried out. It
will be understood, however, that the specific details given in the
examples have been chosen for purposes of illustration only and not
be construed as limiting the invention.
Example 1
[0038] The embodiments shown and described above are only
exemplary. Even though several characteristics and advantages of
the present invention have been set forth in the foregoing
description together with details of the invention, the disclosure
is illustrative only and changes may be made within the principles
of the invention to the full extent indicated by the broad general
meaning of the terms used in herein and in the attached claim.
[0039] FIG. 1 shows a diagram of a preferred system for super
heating water in at least one water heater and mixing hot water and
cold water from a cold water supply. Cold water from an external
source flows into the cold water supply conduit (105) through a
first check valve (101A) and then to a bifurcation (111) in the
cold water supply conduit (105). One bifurcated path is in fluid
communication with a second check valve (101B), which is in fluid
communication with check valve (103) that is in fluid communication
with a cold water supply inlet of a mixing device (150). Ball
valves (104) are used to regulate flow into and out-of the hot
water heater. The second bifurcated path allows water to into the
water heater (110) that is in fluid connection with a cold water
supply conduit (105) through an inlet located on the hot water
heater (110). The cold water supply conduit (105) and the hot water
heater (110) have a pop-off safety valve (170). The hot water
heater (110) also has an outlet in fluid connection with a super
hot water supply conduit system (120). Both the cold water supply
conduit (105) and super hot water supply conduit systems (120) are
in fluid connection with expansion tanks (130). If full demand of
hot water is suddenly stopped, the super heated water will try to
run back out of the water heater causing sold water line to heat
up. The expansion tank on the cold water line allows for hot water
expansion in the cold water line because the super heated water
cannot pass the cold water check valve. The super heated water
supply conduit system (120) is in fluid communication with a third
check valve (101C) that is in fluid communication with a super
heated water supply inlet of the mixing device (150).
[0040] The water heater system as shown in FIG. 1, is capable of
running a laundromat having about 40 washers with no problems
maintaining hot water supply during peak demand times. The water
heater system, is also capable of running more washers with a
storage tank, as shown in FIG. 3. For example, an embodiment of the
system can utilize one water heater 199,000 BTU and a 500 gallon
storage tank having a circulating pump between the storage tank and
water heater. The modified system is capable of serving a
laundromat having about 86 top load washers using about 14 gallons
of hot water for each approximate 22 minute cycle with little or no
problems meeting the hot water demand.
[0041] Although the system of FIG. 1 is shown with one water
heater, at least a second water heater may be connected to the
system depending on the type of hot water demand that is needed.
This second water heater can be used as a back up heater if the
first heater needs service. The additional hot water heater may be
used when the demand for hot water is extremely high for more than
about 2-7 hours. Additionally, the heaters could be cycled, where
one heater could be used one week, and the other would run the next
week. For example, FIG. 2 shows a diagram of a preferred system for
super heating water in at least two water heaters and mixing hot
water and cold water from a cold water supply. Cold water from an
external source flows into the cold water supply conduit (105)
through a first check valve (101A) and then to a bifurcation (111)
in the cold water supply conduit (105). One bifurcated path is in
fluid communication with a second check valve (101B), which is in
fluid communication with check valve (103) that is in fluid
communication with a cold water supply inlet of a mixing device
(150). Ball valves (104) are used to regulate flow into and out-of
the hot water heaters. The second bifurcated path allows water to
into a first and a second hot water heater (110) that is in
parallel fluid connection with a cold water supply conduit (105)
through an inlet located on each of the hot water heaters (110).
The cold water supply conduit (105) and each hot water heater (110)
have a pop-off safety valve (170). Each hot water heater (110) also
has an outlet in parallel fluid connection with a super hot water
supply conduit system (120). Both the cold water supply conduit
(105) and super hot water supply conduit systems (120) are in fluid
connection with expansion tanks (130). The super heated water
supply conduit system (120) is in fluid communication with a third
check valve (101C) that is in fluid communication with a super
heated water supply inlet of the mixing device (150).
[0042] FIG. 3 shows another example of a system for super heating
water in at least one water heater and mixing hot and cold water to
obtain water of a desired temperature. Cold water from an external
source flows into the cold water supply conduit (105). Ball valves
(104) and check valves (103) are used to regulate flow into and out
of a water heater (110). Both the cold water supply conduit (105)
and super hot water supply conduit systems (120) are in fluid
connection with expansion tanks (130). The hot water heater (110)
has an outlet in parallel fluid connection with a super hot water
supply conduit system (120) that is in fluid communication with a
super heated water supply inlet of the mixing device (150). The
water discharged (180) from the mixing device (150) may be in
contact with a thermometer (195) and a temperature safety device
(185). The water discharged (180) from the mixing device (150)
travels to a storage tank (194). The safety tank is in fluid
communication with a thermometer (184) and a pressure safety device
(170). The water discharged (180) from the storage tank (194) is
regulated by a ball valve (104) and is available for use. The
example shown in FIG. 3 further comprises a mechanism for
recirculation of water from the storage tank (194) to the water
heater (110) through the action of a circulating pump (190).
[0043] The temperature safety device (185) is capable of monitoring
the temperature of the water discharged (180) from the mixing
device (150) and shutting down the apparatus if the temperature
deviates from a given temperature range or number. One of ordinary
skill in the art recognizes that a wide variety of temperature
safety devices or similar devices could be utilized, including
commercially available devices from Aquastat or Flowmaster.
[0044] The pressure safety device (170) is capable of monitoring
the temperature of the water discharged (180) from the storage tank
(194) and shutting down the apparatus if the pressure deviates from
a given acceptable range or number. One of ordinary skill in the
art recognizes that a wide variety of pressure safety devices or
similar devices could be utilized.
[0045] The storage tank (194) may be commercially obtained from a
vendor such as Weben-Jarco, Inc., Williams & Davis, Inc., or
Hamilton Engineering. One of ordinary skill in the art recognizes
that a wide variety of storage tanks or similar devices could be
utilized.
[0046] The circulating pump (190) may be commercially obtained from
a vendor such as Gentry, and may vary in capacity depending on the
size of the system. Examples include pumps such as Dayton, Teel,
SURFLO, Jabso, IR-ARO, Flojet, Giant, Taco, Bell and Gossett,
Grundfos, Sherwood, and Rule. Pumps ranging in capacity from about
1 gallon/minute to about 100 gallons/minute may be appropriate. One
of ordinary skill in the art recognizes that a wide variety of
pumps or similar devices could be utilized, including commercially
available pumps from Bell and Gossett, Inc.
[0047] The mixing device (150) described in FIGS. 1-2 are
commercially available from Conbraco Inc. (Matthews, N.C.). This
valve, one key element of the invention, is a high-velocity valve
capable of delivering over 300 gallons/minute of heated water, even
as high as 600 gallons/minute. Such a valve may range from
approximately 1 inch to 4 inches in diameter. This valve is
described in detail in U.S. Pat. No. 6,328,219 issued to Taylor et
al., on Dec. 11, 2001 and titled "Temperature-Responsive Mixing
Valve," ("the '219 patent") the entire content of which is herein
incorporated by reference. Generally, the '219 patent is one type
of mixing valve that is useful for this invention comprises a
temperature-actuated mixing valve for controlling outlet
temperature in a fluid flow system including a valve housing having
first and second fluid supply inlets for introducing first and
second respective supply fluids and a fluid outlet for dispensing a
fluid at a predetermined outflow temperature. The mixing valve
includes a shuttle assembly positioned in the housing. The shuttle
assembly includes a valve member mounted for movement within the
housing responsive to the temperature of the supply fluids to vary
the mixture ratio of the first and second supply fluids as required
to dispense fluid at the predetermined outflow temperature. A
shuttle member is positioned within the valve member and is
moveable as a unit therewith within a predetermined range of motion
responsive to supply fluid temperature variation. A thermal
actuator is provided of the type which converts thermal energy into
mechanical movement by movement of a piston. A first end of the
thermal element engages the movable shuttle member and an opposing
second end engages a stationary portion of the housing whereby
movement of the piston of the thermal actuator produces
corresponding movement of the valve member. An overtravel spring is
captured in a tensioned condition between the valve member and the
shuttle member for maintaining the shuttle member and the valve
member in a stationary condition relative to each other within the
predetermined range of motion of the valve member and for
permitting movement of the shuttle member relative to the valve
member sufficient to accommodate movement of the piston of the
thermal actuator when the valve member has reached its limit of
travel without accommodating the full extent of movement of the
piston of the thermal actuator.
[0048] One of ordinary skill in the art understands that hot water
mixing valves similar to the system described above can be
utilized.
[0049] One of ordinary skill in the art understands that there are
several similar types of water heaters that can be utilized with
the system described above. Some examples of water heaters are: the
AO Smith Cyclone Model BTH-199; Reem Vangaurd Grainger Model No:
6743; Bradford White Hydrojet Commercial Model D80T-199E-3N; and
other similar water heaters from suppliers such as Weber Jarco,
Reem; A.O. Smith Standard; Bradford White; Hamilton; Dayton;
Larther; Sand Blaster; Lavzerss; Natco; E.V.O; Anderson; and U.S.
Tank Master.
[0050] One of ordinary skill in the art understands that there are
several similar types of ball valves that can be utilized with the
system described above. Some examples of ball valves are: from
Boston USAD9101, USAD 9201; Locke M568; M929 and M935; and other
similar ball valves available from: Boston; U.S. Brass; Asco; Brass
Craft; Watts; Conbraco; Nebco; Jamesbury; Dyna Quip; Afllo; George
Fischer; Capitol; Sharon; Fermco; Beck; Parker; Cash ACME.
Similarly, check valves and relief valves such as Granger No GNN89;
Conbraco Grainger No. 6K088; Watts Grainger No.: 4A815; Wats Loke
No. E96-40L-8-150; Cash ACME Locke No: E579-FWL-2 and Watts Locke
No. E100XL-150; and other similar valves that are available from:
Woodforth; Oatey; P.P.P. Inc.; Studor; Fluidmaster; Pasco;
Kirkhill; soiqia; Anderson; B and K; Dayton; and Dormont.
[0051] One of ordinary skill in the art understands that there are
several similar types of safety pop off valves from: Watts;
Conbraco; Parker, Nebxo; U.S. Brass; Brass Craft; Anderson; Beck;
Capitol; Dayton; Boston; Asco.
[0052] Although a specific example for a laundromat hot water
system was described above, one of ordinary skill in the art will
understand that such a system could be utilized for meeting the hot
water demands of hotels, restaurants, car washes, hospitals,
nursing homes, and other facilities. Additionally, such a system
could be modified to work as pool and spa heaters.
[0053] For conventional hot water heaters, the recovery rate is
typically the amount of time it takes to heat water from about
70.degree. F. to about 120.degree. F. Most recovery rates are
measured in hours, for example if a home or restaurant has a demand
of 100 gallons of hot water (120.degree. F.) per hour ("GPH"), the
water heating system must produce at least 100 gallons of
120.degree. F. hot water per hour to have a 100% recovery rate per
hour. If the home or restaurant has a demand of about 800 gallons
of hot water per hour, the water heating system must produce at
least 800 gallons of hot water per hour to have a 100% recovery
rate per hour. Many large capacity conventional water heaters use
about 1.2-1.4 million BTU's to achieve and maintain hot water to
have about an 800 gal/hour recovery rate. As discussed above, one
way to get a similar recovery rate of 800 gal/hour is to use a bank
of about 6-8 or more conventional hot water heaters having the same
capacity and using the same BTU, which will take normal temperature
water (i.e. about 70.degree. F.) and raise the temperature to about
120.degree. F.
[0054] A more efficient way to achieve the same recovery rate of
about 800 gallons/hour is to use the water heating and high flow
mixing system that is shown in FIG. 1. An efficient range of
operation temperatures for hot water heaters, such as standard hot
water heaters or on demand hot water heaters, is about 140.degree.
F.-160.degree. F. Cold water having a temperature of about
70.degree. F. can be mixed with super heated water having a
temperature of about 160.degree. F., which results in heated water
having a temperature of about 120.degree. F. The super high flow
mixing valve controls the flow of super heated hot water, and the
expansion tanks are used to hold super heated water having a
temperature above 1400F. As demand increases the mixing device
brings more super heated hot water into the system. It is possible
to get about an 800 gal/hour recovery rate using only about 398,000
BTU with at least two heaters, which is about a quarter of the
energy required to maintain hot water for peak demand times in many
large capacity conventional water heaters.
[0055] While the systems and methods of this invention have
described in terms of preferred embodiments, it will be apparent to
those of skill in the art that variations may be applied to the
systems, methods, and in the steps or in the sequence of steps of
the method described herein without departing from the concept,
spirit and scope of the invention. More specifically, it will be
apparent that certain materials that are both functionally and
mechanically related might be substituted for the materials
described herein while the same or similar results would be
achieved. All such similar substitutes and modifications to those
skilled in the art are deemed to be within the spirit, scope and
concept of the invention as defined by the appended claims.
REFERENCES CITED
[0056] The following references, to the extent that they provide
exemplary procedural or other details supplementary to those set
forth herein, are specifically incorporated herein by
reference.
U.S. Patent Documents
[0057] U.S. Pat. No. 6,943,325 issued to Pittman, et al., on Sep.
13, 2005 and titled "Water Heater." [0058] U.S. Pat. No. 6,853,803
issued to Chen, et al., on Feb. 8, 2005 and titled
"High-Performance Water Heater." [0059] U.S. Pat. No. 6,577,817
issued to Harris on Jun. 10, 2003 and titled "Water Heater." [0060]
U.S. Pat. No. 6,328,219 issued to Taylor et al., on Dec. 11, 2001
and titled "Temperature-Responsive Mixing Valve." [0061] U.S. Pat.
No. 4,150,665, issued to Wolfson on Apr. 24, 1979, and titled
"Heater For Hot Tubs and Storage Tanks." [0062] U.S. Pat. No.
2,633,108 issued to Sterick on Oct. 4, 1950 and titled "Sterilizing
Water Heater." [0063] U.S. Pat. No. 1,991,980 issued to Hetzer, on
Aug. 11, 1935 and titled "Water Reclaimer." [0064] U.S. Pat. No.
1,560,528 issued to Baum on Apr. 25, 1924, and titled "Hot Water
Heating System."
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