U.S. patent application number 11/366317 was filed with the patent office on 2007-09-06 for heated fluid distribution apparatus for combined domestic hot water supply and space heating system in closed loop.
This patent application is currently assigned to KYUNG DONG BOILER CO. LTD.. Invention is credited to Tae Young Kwak.
Application Number | 20070205293 11/366317 |
Document ID | / |
Family ID | 38470666 |
Filed Date | 2007-09-06 |
United States Patent
Application |
20070205293 |
Kind Code |
A1 |
Kwak; Tae Young |
September 6, 2007 |
Heated fluid distribution apparatus for combined domestic hot water
supply and space heating system in closed loop
Abstract
A combined domestic hot water supply and space heating system
includes a single water heating system, one or more space heating
systems and a heated fluid distribution apparatus. The apparatus
has piping that provides communication between the apparatus, the
water heating system, the space heating system, a fresh water
source, and a house tap. The apparatus also includes a by-pass heat
exchanger that has a heat source side that communicates with the
water heating system, and a space heating system side that
communicates with the space heating system.
Inventors: |
Kwak; Tae Young; (Irvine,
CA) |
Correspondence
Address: |
PARK LAW FIRM
3255 WILSHIRE BLVD
SUITE 1110
LOS ANGELES
CA
90010
US
|
Assignee: |
KYUNG DONG BOILER CO. LTD.
|
Family ID: |
38470666 |
Appl. No.: |
11/366317 |
Filed: |
March 1, 2006 |
Current U.S.
Class: |
236/21B |
Current CPC
Class: |
F24D 3/08 20130101; F23N
2241/06 20200101; F23N 1/082 20130101 |
Class at
Publication: |
236/021.00B |
International
Class: |
F23N 5/10 20060101
F23N005/10; F23N 1/08 20060101 F23N001/08 |
Claims
1. A heated fluid distribution apparatus for a combined domestic
hot water supply and space heating system, wherein the combined
domestic hot water supply and space heating system comprises a
water heating system and a space heating system, the apparatus
comprising: a) a cold water inlet fitting that is adapted to be
connected to a fresh water source; b) a hot water outlet fitting
that is adapted to be connected to a house plumbing fixture; c) a
water outlet fitting that is adapted to communicate with an inlet
of the water heating system; d) a water inlet fitting that is
adapted to communicate with an outlet of the water heating system;
e) a space inlet fitting that is adapted to communicate with a
space heating system return fitting of the space heating system; f)
a space outlet fitting that is adapted to communicate with a space
heating system inlet fitting of the space heating system; and g) a
by-pass heat exchanger that comprises a heat heat source side that
is adapted to communicate with the water heating system, and a
space heating system side that is adapted to communicate with the
space heating system.
2. The apparatus of claim 1, further comprising a primary loop
circulation pump, and a secondary circulation pump, wherein the
heat source side of the by-pass heat exchanger comprises a source
inlet that is adapted to communicate the water heating system, and
a source outlet that is connected to the primary loop pump, wherein
the space heating system side of the by-pass heat exchanger
comprises a space inlet that is connected to the secondary loop
pump for reheating water from the space heating system and a space
outlet for returning heated water to the space heating system.
3. The apparatus of claim 2, wherein the working fluid directions
are opposite with each other between the heat source side and the
space heating system side in the by-pass heat exchanger.
4. The apparatus of claim 2, further comprising a priority device,
a three way valve and a control board for prioritizing domestic hot
water, wherein the priority device is connected to the control
board, wherein the control board controls activation and
deactivation of the three way valve, the primary circulation pump,
and the secondary circulation pump.
5. The apparatus of claim 4, wherein the control board is adapted
to communicate with a house room thermostat for turning on/off of
the space heating system.
6. The apparatus of claim 4, wherein the three way valve
communicates with the water inlet fitting, the source inlet of the
by-pass heat exchanger, and the hot water outlet fitting.
7. The apparatus of claim 2, further comprising an expansion tank
and an air separator between the space outlet of the by-pass heat
exchanger and the space outlet fitting, wherein the expansion tank
and the air separator balance pressure and automatically eliminate
air in water flows.
8. The apparatus of claim 2, further comprising a thermostatic
mixing valve, which communicates with the space outlet of the
by-pass heat exchanger and the space inlet fitting, and comprises
an outlet that is connected to the space outlet fitting.
9. The apparatus of claim 2, wherein the primary circulation pump
communicates with the source outlet of the by-pass heat exchanger
and the water outlet fitting.
10. The apparatus of claim 9, wherein the primary circulation pump
provides water head that is high enough to activate a flow sensor
for the water heating system.
11. The apparatus of claim 2, wherein the secondary circulation
pump communicates with the space inlet fitting and the space inlet
of the by-pass heat exchanger.
12. The apparatus of claim 11, wherein the secondary circulation
pump has a predetermined flow rate, wherein the predetermined flow
rate is determined depending on the space heating system.
13. The apparatus of claim 1, further comprising an anti-scalding
valve, wherein the anti-scalding valve communicates with the cold
water inlet fitting and the water inlet fitting and has an outlet
that is connected to the hot water outlet fitting.
14. The apparatus of claim 13, wherein the temperature of water
from the anti-scalding valve is set to about 120.degree. F.
15. The apparatus of claim 1, further comprising a temperature and
pressure gauge that indicates incoming hot water temperature from
the outlet of the water heating system.
16. The apparatus of claim 1, further comprising a water check
valve that prevents return water backflow to the cold water inlet
fitting.
17. A combined domestic hot water supply and space heating system
comprising: a) a water heating system; b) a space heating system;
and c) a heated fluid distribution apparatus; wherein the heated
fluid distribution apparatus comprises: 1) a cold water inlet
fitting that is adapted to be connected to a fresh water source; 2)
a hot water outlet fitting that is adapted to be connected to a
house plumbing fixture; 3) a water outlet fitting that communicates
with an inlet of the water heating system; 4) a water inlet fitting
that communicates with an outlet of the water heating system; 5) a
space inlet fitting that communicates with a space heating system
return fitting of the space heating system; and 6) a space outlet
fitting that communicates with a space heating system inlet fitting
of the space heating system; and 7) a by-pass heat exchanger that
comprises a heat heat source side that communicates with the water
heating system, and a space heating system side that communicates
with the space heating system.
18. The system of claim 17, wherein the heated fluid distribution
apparatus further comprises a primary loop circulation pump, and a
secondary circulation pump, wherein the heat source side of the
by-pass heat exchanger comprises a source inlet that is adapted to
communicate the water heating system, and a source outlet that is
connected to the primary loop pump, wherein the space heating
system side of the by-pass heat exchanger comprises a space inlet
that is connected to the secondary loop pump for reheating water
from the space heating system and a space outlet for returning
heated water to the space heating system.
19. The system of claim 17, wherein the water heating system is an
on demand flow through tankless water heater.
20. The system of claim 17, wherein the water heating system is a
fully modulating device, which can supply hot water at a
predetermined temperature ranging from about 100.degree. F. to
about 180.degree. F.
Description
BACKGROUND OF THE INVENTION
[0001] The present invention is related to a system that provides
both domestic hot water and space heating. More particularly, the
invention is related to an apparatus that properly distributes
heated water from a singe water heating system to domestic hot
water and closed loop space heating applications.
[0002] Most building or houses that require a domestic hot water
supply as well as space heating use separate appliances for each
purpose. For example, a conventional tank type gas water heater or
an electric water heater has been used for domestic hot water
supply. Conventional tank type gas heater or electric heater has
disadvantage that it takes significant amount of space and it
continuously lose heat energy due to its stand.
[0003] Conventionally, when space heating is required, a separate
furnace or any hydronic space heater has been used. The furnace or
heater has its own gas burner or electric heating element. This
scheme is inefficient and waste space and energy.
[0004] A more compact and efficient hot water and space heating
system has long been in need.
SUMMARY OF THE INVENTION
[0005] An objective of the present invention is to provide a
compact and efficient combined domestic hot water supply and space
heating system.
[0006] Another objective of the invention is to provide a fast,
safe and reliable combined domestic hot water supply and space
heating system.
[0007] In order to achieve the above objectives, the present
invention provides a heated fluid distribution apparatus for a
combined domestic hot water supply and space heating system. The
combined domestic hot water supply and space heating system
includes a water heating system and a space heating system.
[0008] The heated fluid distribution apparatus includes a cold
water inlet fitting that is adapted to be connected to a fresh
water source, a hot water outlet fitting that is adapted to be
connected to a house plumbing fixture, a water outlet fitting that
communicates with an inlet of the water heating system, a water
inlet fitting that communicates with an outlet of the water heating
system, a space inlet fitting that communicates with a space
heating system return fitting of the space heating system, a space
outlet fitting that communicates with a space heating system inlet
fitting of the space heating system, and a by-pass heat exchanger
that comprises a heat source side that communicates with the water
heating system, and a space heating system side that communicates
with the space heating system.
[0009] The apparatus further includes a primary circulation pump
and a secondary circulation pump. The heat source side of the
by-pass heat exchanger includes a source inlet that is adapted to
communicate the water heating system, and a source outlet that is
connected to the primary loop pump, wherein the space heating
system side of the by-pass heat exchanger includes a space inlet
that is connected to the secondary loop pump for reheating water
from the space heating system and a space outlet for returning
heated water to the space heating system. The working fluid
directions are opposite with each other between the heat source
side and the space heating system side in the by-pass heat
exchanger.
[0010] The apparatus further includes a priority device, a three
way valve and a control board for prioritizing domestic hot water.
The priority device is connected to the control board. The control
board controls activation and deactivation of the three way valve,
the primary circulation pump, and the secondary circulation pump.
The control board is adapted to communicate with a house room
thermostat for turning on/off of the space heating system.
[0011] The three way valve communicates with the water inlet
fitting, the source inlet of the by-pass heat exchanger, and the
hot water outlet fitting.
[0012] The apparatus further includes an expansion tank and an air
separator between the space outlet of the by-pass heat exchanger
and the space outlet fitting. The expansion tank and the air
separator balance pressure and automatically eliminate air in water
flows.
[0013] The apparatus further includes a thermostatic mixing valve,
which communicates with the space outlet of the by-pass heat
exchanger and the space inlet fitting, and includes an outlet that
is connected to the space outlet fitting.
[0014] The primary circulation pump communicates with the source
outlet of the by-pass heat exchanger and the water outlet fitting.
The primary circulation pump provides water head that is high
enough to activate a flow sensor for the water heating system.
[0015] The secondary circulation pump communicates with the space
inlet fitting and the space inlet of the by-pass heat exchanger.
The secondary circulation pump has a predetermined flow rate, which
is determined depending on the space heating system.
[0016] The apparatus further includes an anti-scalding valve,
wherein the anti-scalding valve communicates with the cold water
inlet fitting and the water inlet fitting and has an outlet that is
connected to the hot water outlet fitting. The temperature of water
from the anti-scalding valve is set to about 120.degree. F.
[0017] The apparatus further includes a temperature and pressure
gauge that indicates incoming hot water temperature from the outlet
of the water heating system.
[0018] The apparatus further includes a water check valve that
prevents return water backflow to the cold water inlet fitting.
[0019] The water heating system is an on demand flow through
tankless water heater. Alternatively, the water heating system is a
fully modulating device, which can supply hot water at a
predetermined temperature ranging from about 100.degree. F. to
about 180.degree. F.
[0020] The present invention utilizes an on-demand water heater,
which is small enough to hang on a wall, as a water heating system.
Sine the water heater has no reservoir tank, the water heater takes
significantly less space compared to conventional water heater.
Fully modulating computer controlled gas valve brings out
significant energy saving. Automatic flow adjustment valve supplies
hot water at desired temperature without temperature fluctuations.
Various sizes of input water heating system can be used
anywhere.
[0021] The present invention wisely controls conjunction of hot
water supply and space heating with flow through type water heating
system and space heating. Combining domestic hot water and space
heating system involves a lot of confusion and difficulties in
practice especially in controlling heat generation system, heated
water temperature and flow rate.
[0022] The present invention supplies and maintains potable
domestic hot water at steady temperature, maximizes efficiency in
output BTU in supplying hot water, and maximizes efficiency in
space heating by optimized control for radiant floor heating
system, snow melting system, base board heating system, or force
air heating system with a single flow through water heating system.
The single flow through water heating system adopts an on-demand
tankless water heater or an instantaneous water heater.
[0023] The present invention utilizes an open loop system and a
closed loop system simultaneously. The open loop system is used for
domestic hot water supply, and the closed loop system is used for
space heating.
[0024] The present invention may be applied for various space
heating system and wide area applications. For flow through water
heating system that offers between 110,000 BTU/hour to 350,000
BTU/hour, the present invention can continuously produce hot water
from 2 GPM to 12 GPM with 77.degree. F. rise from ground water
temperature. The present invention uses this hot water effectively
to the combination of domestic hot water supply and space
heating.
[0025] The distribution apparatus is used for distributing heated
water to potable domestic hot water supply and space heating with
the single water heating system.
[0026] The apparatus includes the priority device for supplying
domestic hot water, the anti-scalding device, the by-pass heat
exchanger, the circulation pump for space heating, the circulation
pump for the primary loop, and safety and performance devices.
[0027] The single water heating system is a flow through type, and
has the inlet for replenishing the system with unheated water and
the outlet for supplying heated water. The water heating system can
be set to provide hot water at 100.degree. F..about.180.degree. F.
depending on the space heating system.
[0028] The space heating system includes a radiant in floor space
heating, base board space heating and forced fan assistant space
heating system. The temperature drop through the space heating
system is designed to 14.degree. F..about.35.degree. F. on average
using predetermined water flow rate and hot water temperature.
[0029] The by-pass heat exchanger transfers heat in 200,000 BTU/hr
from one liquid medium to another with no intermixing of the two
mediums.
[0030] Although the present invention is briefly summarized, the
fuller understanding of the invention can be obtained by the
following drawings, detailed description and appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0031] These and other features, aspects and advantages of the
present invention will become better understood with reference to
the accompanying drawings, wherein:
[0032] FIGS. 1a and 1b are perspective views of a heated fluid
distribution apparatus for a combined hot water supply and space
heating system according to the present invention;
[0033] FIG. 2 is a schematic diagram showing the heated fluid
distribution apparatus;
[0034] FIG. 3 is a schematic diagram showing the combined hot water
supply and space heating system;
[0035] FIG. 4 is a schematic diagram showing a water heating
system; and
[0036] FIGS. 5a and 5b are schematic diagrams showing space heating
devices.
DETAILED DESCRIPTION OF THE INVENTION
[0037] FIGS. 1a and 1b show a heated water distributing apparatus
32 according to the present invention. FIG. 2 shows that the
apparatus 32 has a cold water inlet fitting 21 for connection to a
filtered and treated water source (not shown) as a potable fresh
water source. The apparatus 32 also has a hot water outlet fitting
23 that delivers domestic hot water at a predetermined temperature,
which is set about 120.degree. F. The domestic hot water outlet
fitting 23 normally supplies the household potable hot water via
potable hot water taps or any plumbing fixtures that use potable
hot water.
[0038] FIG. 3 shows that the apparatus 32 has a water inlet fitting
24 that is connected to an outlet 2 of a water heating system 31.
The apparatus 32 has a water outlet fitting 22 that is connected to
an inlet 1 of the water heating system 31 for replenishing unheated
water.
[0039] The water heating system 31 is an on demand flow through
tankless water heater, and uses gas (Natural gas or Propane gas) or
electricity. Alternatively, the water heating system 31 is a fully
modulating device, which can supply hot water at a predetermined
temperature ranging from about 100.degree. F. to about 180.degree.
F.
[0040] The cold water inlet fitting 21, the water inlet fitting 24,
the water outlet fitting 22, the hot water outlet fitting 23 of the
apparatus 32, and the inlet 1 and the outlet 2 of the water heating
system 31 are made of 3/4'' copper pipe and fittings.
[0041] The apparatus 32 has a space outlet fitting 20 that is
connected to a space heating system inlet fitting 27 or 29 as a
heated water supply fitting, and a space inlet fitting 19 that is
connected to a space heating return fitting 28 or 30 as a return
conduit for reheating water. The space inlet fitting 19 and the
space outlet fitting 20 of the apparatus are made of 1'' copper
pipe.
[0042] Referring to FIG. 2, the apparatus 32 has an anti-scalding
device 9 for setting domestic hot water supply at 120.degree. F.
The anti-scalding device 9 is connected to the inlet fitting 24 and
the cold water inlet fitting 21, and it has an outlet that is
connected to the hot water outlet fitting 23.
[0043] The apparatus 32 has a priority device 8 for prioritizing
domestic hot water. The priority device 8 is connected to the
control board 26. The control board 26 controls activation and
deactivation of a three way valve 11, a primary circulation pump
15, and a secondary circulation pump 16.
[0044] The apparatus 32 has a temperature and pressure gauge 7 that
indicates incoming hot water temperature from the outlet 2 of the
water heating system 31. The temperature is between 100.degree.
F..about.180.degree. F. depending on the temperature set in the
water heating system 31. The temperature and pressure gauge 7 is
used to prevent high temperature replenish water.
[0045] The apparatus 32 includes a water check valve 14 that
prevents return water backflow to the cold water inlet fitting
21.
[0046] The apparatus 32 includes a by-pass heat exchanger 25. The
by-pass heat exchanger 25 transfers heat from the water heating
system 31 to the space heating system 33, 34. The by-pass heat
exchanger 25 includes a source inlet 46 communicating with the
outlet 2 of the water heating system 31, and a source outlet 47
that is connected to the inlet of the primary loop pump 15 as
connections to the heat source side 56. The by-pass heat exchanger
25 includes a space inlet 49 for reheating water from the space
heating system 33, 34 and a space outlet 48 for returning heated
water to the space heating system 33, 34 as connections to the
space heating system side 58. As shown by arrows in FIG. 2, working
fluid directions are opposite with each other between the heat
source side 56 and the space heating system side 58 in the by-pass
heat exchanger 25.
[0047] The primary circulation pump 15 communicates with the source
outlet 47 of the by-pass heat exchanger 25 and the water outlet
fitting 22. The primary circulation pump 15 provides water head
that is high enough to activate a flow sensor 54 for the water
heating system 31.
[0048] The secondary circulation pump 16 communicates with the
space inlet fitting 19 and the space inlet 49 of the by-pass heat
exchanger 25. The secondary circulation pump 16 has a predetermined
flow rate, which is determined depending on the space heating
system 31.
[0049] The apparatus 32 has an air separator 10, an expansion tank
13 and a pressure regulator 12 for adjusting heated water pressure
in space heating systems 33, 34 (refer to FIG. 3). The expansion
tank 32 and the air separator 10 are provided between the space
outlet 48 of the by-pass heat exchanger 25 and the space outlet
fitting 20. The expansion tank 32 and the air separator 10 balance
pressure and automatically eliminate air in water flows.
[0050] The apparatus 32 has a thermostatic mixing valve 17, which
has an inlet that is connected to the space outlet 48, and another
inlet that is connected to the space inlet fitting 19, and an
outlet that is connected to the space outlet fitting 20 for
supplying tempered hot water to the space heating system. As
explained above, the space inlet fitting 19 is connected to the
space heating return fitting 28 of the space heating system 33 or
the space heating return fitting 30 of the space heating system 34.
The space outlet fitting 20 is connected to the space heating
system inlet fitting 27 of the space heating system 33 or to the
space heating system inlet fitting 29 of the space heating system
34. The thermostatic mixing valve 17 keeps preset heated water
supply temperature around 120.degree. F. for the radiant space
heating system or snow melting system 33 and above 140.degree. F.
for the forced air space heating system 34.
[0051] The apparatus 32 has the secondary circulation pump 16
between the space inlet fitting 19 and the space inlet 49 of the
by-pass heat exchanger 25 for circulating heated media in closed
loop for the space heating system 33, 34.
[0052] When temperature drops between the space outlet fitting 20
and the space inlet fitting 19 around 14.degree.
F..about.35.degree. F. from the supply temperature depends on the
space heating system 33, 34.
[0053] A house space heating thermostat 44 is connected to the
control board 26 of the apparatus 32 for activating a space heating
mode. When the space heating thermostat 44 is engaged to start, the
control board 26 starts the secondary circulation pump 16, which
circulates heated water through the space heating circuit. The
temperature of circulated water is set around 110.degree. F. for a
radiant floor heating system and a snow melting system, around
180.degree. F. for a base board heating system. The heated water
supply temperature is set above 140.degree. F. for a forced air
space heating system. For the above space heating systems, the
heated water temperature drops 14.degree. F..about.35.degree. F.
from the supply temperature by design.
[0054] The domestic hot water capacity is from 2 GPM to 10 GPM
depending on the input rate of the water heating system 31.
[0055] The operation of the invention is explained. If there is a
request for domestic hot water supply through the domestic hot
water outlet fitting 23, fresh cold water is supplied through the
cold water inlet fitting 21. Immediately after the cold water
supply, the priority device 8 communicates to the control board 26,
and the control board 26 controls the three way valve 11 and the
primary circulation pump 15 to change to a bypass mode in which the
whole system is operated for providing domestic hot water to
household plumbing fixtures. The three way valve 11 communicates
with the water inlet fitting 24, the source inlet 46 of the by-pass
heat exchanger 25, and the hot water outlet fitting 23.
[0056] If there is no request for domestic hot water supply, and a
thermostat for house space heating sends request for heating, the
whole system is operated only for space heating with closed loop
system until domestic hot water supply is requested.
[0057] The room air temperature in the bypass mode may drop
2.degree. F..about.10.degree. F. from the room air temperature
before the bypass mode is activated in about 20 minutes. The
temperature drop depends on the heat insulation rate of the
house.
[0058] The apparatus 32 of the present invention with the single
water heating system 31 and the space heating systems 33, 34 can
satisfy most of domestic hot water requirements for traditional
household plumbing fixtures. The relationship between the input
capacity and hot water flow rate is explained under the
predetermined temperature of 120.degree. F. for the anti-scalding
device 9.
[0059] Basic Equation for apparatus 32 that produces hot water as
is, and in case that the hot water temperature of the water heating
system 31 is set above 120.degree. F. Input BTU.times.Efficiency
(%)=500.times.GPM .times..DELTA.T
[0060] Where [0061] Input BTU by BTU/hour [0062] .DELTA.T=preset
temperature--fresh cold water temperature [0063] GPM as gallons per
minute
[0064] Actual GPM with 120.degree. F. can be predicted with the
following equation: GH=(TM-TC)/(TH-TM)
[0065] Where [0066] GH: Gallon of hot water requirement for one
gallon of cold water [0067] TM: Cold and hot water mixture
temperature (The apparatus is set as TM=120.degree. F.) [0068] TC:
Fresh cold water temperature [0069] TH: Output hot water
temperature in the water heating system
[0070] The input BTU may be changed depending on each house's
domestic hot water requirement and/or space heating
requirement.
[0071] While the invention has been shown and described with
reference to different embodiments thereof, it will be appreciated
by those skilled in the art that variations in form, detail,
compositions and operation may be made without departing from the
spirit and scope of the invention as defined by the accompanying
claims.
* * * * *