U.S. patent application number 12/563647 was filed with the patent office on 2010-03-18 for self contained water-to-water heat pump.
Invention is credited to James William Slaughter.
Application Number | 20100064710 12/563647 |
Document ID | / |
Family ID | 42006012 |
Filed Date | 2010-03-18 |
United States Patent
Application |
20100064710 |
Kind Code |
A1 |
Slaughter; James William |
March 18, 2010 |
SELF CONTAINED WATER-TO-WATER HEAT PUMP
Abstract
A self-contained water-to-water heat transfer system is provided
that mixes hot water produced by a heat exchange with cold output
fluid expelled from the heat pump to make source fluid. More
specifically, in order to reduce the fluid flow rate required
within a heat pump and substantially prevent freezing of evaporator
coils within the heat pump, source water fed into the heat pump is
taken from a mixture of the output hot water that was generated in
the heat pump and the cool water exiting the heat pump. The system
alleviates the need to employ a ground loop outside of a structure
that is required by traditional geothermal heating systems.
Inventors: |
Slaughter; James William;
(Delta, CO) |
Correspondence
Address: |
SHERIDAN ROSS PC
1560 BROADWAY, SUITE 1200
DENVER
CO
80202
US
|
Family ID: |
42006012 |
Appl. No.: |
12/563647 |
Filed: |
September 21, 2009 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
11775739 |
Jul 10, 2007 |
|
|
|
12563647 |
|
|
|
|
60806902 |
Jul 10, 2006 |
|
|
|
Current U.S.
Class: |
62/238.7 ;
62/238.6 |
Current CPC
Class: |
F24D 2200/12 20130101;
F24D 2200/24 20130101; Y02B 30/00 20130101; Y02B 30/52 20130101;
F24D 11/0214 20130101; F25B 2339/047 20130101; F25B 29/003
20130101; F24D 3/12 20130101; Y02B 30/24 20130101; Y02B 10/70
20130101; Y02B 10/40 20130101 |
Class at
Publication: |
62/238.7 ;
62/238.6 |
International
Class: |
F25B 30/00 20060101
F25B030/00 |
Claims
1. A self-contained water-to-water heat transfer system comprising:
a first heat exchanger; a second heat exchanger; a refrigerant
conduit interconnecting said first heat exchanger to said second
heat exchanger in a closed circuit; a compressor associated with
said refrigerant conduit; an expansion valve associated with said
refrigerant conduit; a first fluid input conduit in communication
with said first heat exchanger; a first fluid output conduit in
communication with said first heat exchanger; a second fluid input
conduit in communication with said second heat exchanger; a second
fluid output conduit in communication with said second heat
exchanger; and a fluid conduit in communication with said first
fluid output conduit and said second fluid input conduit, wherein a
portion of fluid positioned within said first fluid output conduit
is directed to said second fluid input conduit, thereby providing
heat to refrigerant positioned within said second heat
exchanger.
2. The system of claim 1, further comprising a first valve
associated with said second fluid input conduit for controlling the
fluid flow thereof.
3. The system of claim 1, wherein fluid in said first fluid input
conduit is about 135 degrees Fahrenheit, fluid in said first fluid
output conduit is about 143 degrees Fahrenheit, fluid in said
second fluid input conduit is about 143 degrees Fahrenheit, and the
fluid in said second fluid output conduit is about 61 degrees
Fahrenheit
4. The system of claim 1, wherein the fluid and the first fluid
input conduit is flowing at about 12 gallons per minute, the fluid
flowing in the first fluid output conduit is flowing at about 12
gallons per minute, the fluid flowing in said second fluid input
conduit is about 0.8 gallons per minute and the fluid flowing in
said second fluid output conduit is flowing at about 0.8 gallons
per minute.
5. The system of claim 1, wherein said first heat exchanger is a
condenser and said second heat exchanger is an evaporator.
6. The system of claim 1, wherein the change of energy between the
first fluid input conduit and the first fluid output conduit is
about 48,690 BTU/hr and the difference in energy of the second
fluid input conduit and the fluid in the second fluid output
conduit is about 33,120 BTU/hr.
7. The system of claim 1, wherein the majority of the fluid exiting
from the first fluid output conduit is directed to a storage
tank.
8. The system of claim 7, wherein the storage tank includes an
outlet conduit associated with at least one of a indoor heater and
an infloor heating system wherein the fluid directed thereto is
redirected to said storage tank after a predetermined time.
9. The system of claim 1, further comprising a pump associated with
at least one of said first fluid input conduit, said first fluid
outlet conduit, said second fluid input conduit, and said second
fluid output conduit.
10. A self-contained water-to-water heat transfer system
comprising: a heat pump having a source side with a first fluid
input conduit and a first fluid output conduit and a load side with
a second fluid input conduit and a second fluid output conduit; a
fluid conduit in communication with said first fluid output conduit
and said second fluid input conduit, wherein a portion of fluid
positioned within said first fluid output conduit is directed to
said second fluid input conduit.
11. The system of claim 10 wherein said heat pump comprises a first
heat exchanger; a second heat exchanger; a refrigerant conduit
interconnecting said first heat exchanger to said second heat
exchanger in a closed circuit; a compressor associated with said
refrigerant conduit; an expansion valve associated with said
refrigerant conduit; wherein said first fluid input conduit in
communication with said first heat exchanger; wherein said first
fluid output conduit in communication with said first heat
exchanger; wherein said second fluid input conduit in communication
with said second heat exchanger; and wherein said second fluid
output conduit in communication with said second heat
exchanger.
12. The system of claim 10, further comprising a first valve
associated with said second fluid input conduit for controlling the
fluid flow thereof.
13. The system of claim 10, wherein fluid in said first fluid input
conduit is about 135 degrees Fahrenheit, fluid in said first fluid
output conduit is about 143 degrees Fahrenheit, fluid in said
second fluid input conduit is about 143 degrees Fahrenheit, and the
fluid in said second fluid output conduit is about 61 degrees
Fahrenheit
14. The system of claim 10, wherein the fluid and the first fluid
input conduit is flowing at about 12 gallons per minute, the fluid
flowing in the first fluid output conduit is flowing at about 12
gallons per minute, the fluid flowing in said second fluid input
conduit is about 0.8 gallons per minute and the fluid flowing in
said second fluid output conduit is flowing at about 0.8 gallons
per minute.
15. The system of claim 11, wherein said first heat exchanger is a
condenser and said second heat exchanger is an evaporator.
16. The system of claim 10, wherein the change of energy between
the first fluid input conduit and the first fluid output conduit is
about 48,690 BTU/hr and the difference in energy of the second
fluid input conduit and the fluid in the second fluid output
conduit is about 33,120 BTU/hr.
17. The system of claim 10, wherein the majority of the fluid
exiting from the first fluid output conduit is directed to a
storage tank.
18. The system of claim 17, wherein the storage tank includes an
outlet conduit associated with at least one of a indoor heater and
an infloor heating system wherein the fluid directed thereto is
redirected to said storage tank after a predetermined time.
19. The system of claim 10, further comprising a pump associated
with at least one of said first fluid input conduit, said first
fluid outlet conduit, said second fluid input conduit, and said
second fluid output conduit.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part of U.S. patent
application Ser. No. 11/775,739, filed Jul. 10, 2007, which claims
the benefit of U.S. Provisional Patent Application Ser. No.
60/806,902, filed Jul. 10, 2006, the entire disclosure of each are
incorporated by reference herein.
FIELD OF THE INVENTION
[0002] The present invention relates generally to a thermoelectric
apparatus that transfers thermal energy from one location to
another that can be used alternatively to either heat or cool an
area.
BACKGROUND OF THE INVENTION
[0003] Heat pumps are basically air conditioning units that
function in reverse and are commonplace in many residential and
commercial structures. The most common air-to-air pumps employ a
conduit filled with a thermally conductive coolant, such as Freon,
that transfers heat taken from the air outside of the structure
into the structure. The vapor compression cycle that facilitates
the heat transfer comprises generally a conduit that carries high
pressure, high temperature liquid coolant to an expansion valve
that reduces the pressure of the coolant, thereby lowering its
temperature and pressure. The now low temperature coolant is then
directed to an evaporator, which is generally a system of coiled
tubes that act as a heat exchanger. The fluid in the evaporator is
placed in thermal communication with the air outside the structure
so that the heat from the air is transferred to the coolant in the
evaporator. Hot coolant vapor exits the evaporator and is
compressed and directed to a condenser where it is placed in
thermal communication with air inside the structure. To complete
the vapor compression cycle, the hot liquid coolant that exits the
condenser is pumped into the expansion valve.
[0004] The major drawback with air-to-air systems is that they are
not very efficient in the winter. More specifically, when the
outside temperature is at or below about 35.degree. F., heat is
less easy to extract. Thus, in most locations, a furnace, a stove
or a fireplace, for example, must be employed during colder periods
to heat the structure. Further, air-to-air heat exchange systems
are prone to damage and degradation since they must be located
outside of the structure.
[0005] Water-to-water heat transfer systems also exist that are
more efficient than air-to-air systems, one common system employing
a ground source heat pump that obtains the required thermal energy
from beneath the surface of the earth as opposed to the air around
a structure. More specifically, the temperature of the ground or
groundwater a few feet beneath the earth's surface remains
relatively constant throughout the year, even though the outdoor
air temperature may fluctuate greatly with the change of seasons.
For example, at a depth of approximately 6 feet, the temperature of
the soil in most of the world's regions remains stable between
about 45.degree. and 70.degree. F. Thus there exists a constant and
ready supply of heat to be pulled from the ground and used as a
source of heat for a heat pump to heat the structure, for example.
These "geo-exchange" heat pumps utilize the earth's natural heat
that is collected in winter through a series of pipes, generally
referred to an "earth loop" or "ground loop," installed below the
surface of the ground or submerged in a pond or lake. An indoor
heat exchange system then uses electrically driven compressors and
heat exchangers in a vapor compression cycle to concentrate the
earth's heat energy and selectively release it inside the dwelling
at a higher temperature. As one skilled in the art will appreciate,
the process can be reversed in the summer to cool the dwelling.
Approximately 70% of the energy used in a geo-exchange heating and
cooling system is renewable from the ground. Further, once
installed, the earth loop in a geo-exchange system remains out of
sight beneath the earth's surface while it works unobtrusively to
tap the heating and cooling nature provides. The earth loops for a
residential geo-exchange systems are installed either horizontally
or vertically in the ground, or submerged in water in a pond or
lake. In most cases, the fluid runs through a loop in a closed
system, but open loop systems may be used where local codes permit.
Each type of loop configuration has its own, unique advantages and
disadvantages.
[0006] Horizontal ground closed loops are usually the most
effective when adequate yard space is available and trenches are
easy to dig. Trenchers or back hoes are employed to dig trenches
about 3-6 feet below the ground wherein a series of parallel
plastic pipes are placed in a closed loop. The trench is then
back-filled while care is taken not to allow sharper objects to
damage the pipes. A typical horizontal loop will be about 400-600
feet long per ton of heating and cooling capacity required. The
buried or submerged pipe may be coiled in order to fit more of it
into shorter trenches, but, while this reduces the amount of land
space needed, it may require more pipe to achieve the same results
as a single spread out pipe that can more efficiently extract or
deposit thermal energy. Horizontal ground loops are easiest to
install at a home that is under construction. However, new types of
digging equipment that allow horizontal boring are making it
possible to retrofit geo-exchange systems into existing homes with
minimal disturbance to lawns. Horizontal boring machines can even
allow loops to be installed under existing buildings or driveways,
however such retrofitting, can be very expensive. Unfortunately,
many homes being built today are in sub-divisions wherein space is
limited and the use of a horizontal earth loop is not feasible.
[0007] To compensate for limited area, a vertical ground closed
loop may be employed which is ideal for homes where yard space is
insufficient or for large structures that require large heating and
cooling loads. Vertical earth loops are also ideal when the earth
is rocky close to the surface, or for retrofit applications where
minimum disruption of landscaping is desired, wherein each hole
contains a single loop of pipe with a u-bend at the bottom. After
the pipe is inserted, the hole is back-filled or grouted. Each
vertical pipe is then connected to a horizontal pipe, which may
also be concealed underground, that carries fluid in a closed
system to and from the geo-exchange system. Vertical loops are
generally more expensive to install, but require less piping than
horizontal loops because the earth at greater depths is
alternatingly cooler in the summer and warmer in the winter. For
example, a five ton system generally requires five holes each about
200 feet deep to be effective, which equates to 1000 feet of
drilling that generally costs about $15 per foot for a total cost
of about $15,000.00. Thus it is a long felt need in its field of
home heating and cooling to provide a system that is easy to
install and that efficiently heats a structure without the cost
associated with traditional geo-exchange heating systems. The
following disclosure describes an improved system for utilizing a
self contained water-to-water heat pump that does not require a
ground loop.
SUMMARY OF THE INVENTION
[0008] It is one aspect of the present invention to provide a
self-contained water-to-water heat transfer system that does not
require the use of a ground loop as commonly employed in
geo-exchange heating systems. That is, embodiments of the present
invention utilize a novel method of mixing cooler water that exits
a water-to-water heat pump with heated water also exiting the heat
pump, and directing this mixture back into the heat pump so it can
be more effectively used in a vapor compression cycle. One skilled
in the art will appreciate that additional compression may be
needed in order to sustain the temperature of the water exiting the
heat pump, but the system as contemplated herein is more efficient
than air-to-air heat pumps and do not have the drawbacks inherent
in ground loop systems and/or air-to-air systems.
[0009] More specifically, one advantage of the system is that there
is no need to drill or alter the landscape to provide a location
for ground loops, thus, the system is less expensive to implement.
Embodiments of the present invention are also self-contained
wherein a single conduit system is employed that includes segments
of varying temperatures that define the vapor compression cycle. In
addition, due to the system's size and lack of external
componentry, it may be located indoors, thereby avoiding outside
exposure concerns such as temperature fluctuations and moisture.
Further, since hot water (i.e. hotter than the fluid heated by the
ground that enters the heat pump in a traditional system), is
directed into the heat pump as the source of heat energy, the mass
flow through the heat pump may be slowed dramatically. More
specifically, prior art systems require a source mass flow of about
12-15 gallons per minute to prevent the coolant in the evaporator
from freezing. In embodiments of the present invention, the
temperature of the source fluid is about 95.degree. F., thereby
preventing coolant freezing. Thus the flow rate of source fluid may
be slowed and a smaller more energy efficient source pump may be
utilized.
[0010] It is another aspect of the present invention to provide a
system that is easily incorporated onto current water-to-water heat
pumps. That is, water-to-water heat pumps that use an external
source to heat source water may be altered by the addition of
embodiments of the present invention where the source of heat
energy is replaced by the aforementioned preheating scheme.
[0011] It is still yet another aspect of the present invention to
provide a system that can be used with traditional ground source
heat exchange systems of the prior art. That is, embodiments of the
present invention may be employed along with a traditional ground
source earth loops wherein a single loop provides source heat that
is directed to a plurality of self-contained heat pumps. Since the
ground loop water is substantially cooler than the heated water
generated by the heat pump, a mixing valve, tee, or any other
common fluid mixing device may be used to direct water from the
traditional ground source heat pumps into a portion of the hot
water exiting the heat pump to provide source water that prevents
evaporator coils from freezing as described above.
[0012] The Summary of the Invention is neither intended nor should
it be construed as being representative of the full extent and
scope of the present invention. The present invention is set forth
in various levels of detail in the Summary of the Invention as well
as in the attached drawings and the Detailed Description of the
Invention and no limitation as to the scope of the present
invention is intended by either the inclusion or non-inclusion of
elements, components, etc. in this Summary of the Invention.
Additional aspects of the present invention will become more
readily apparent from the Detail Description, particularly when
taken together with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The accompanying drawings, which are incorporated in and
constitute a part of the specification, illustrate embodiments of
the invention and together with the general description of the
invention given above and the detailed description of the drawings
given below, serve to explain the principles of these
inventions.
[0014] FIG. 1 is a schematic of a ground source heat pump system of
the prior art;
[0015] FIG. 2 is another schematic of a ground source heat pump
system of the prior art;
[0016] FIG. 3 is a schematic of a self-contained water-to-water
heat pump system of one embodiment of the present invention;
[0017] FIG. 4 is a schematic of a heat pump employed in the
embodiment of the present invention shown in FIG. 3; and
[0018] FIG. 5 is a schematic of a self-contained water-to-water
heat pump system of another embodiment of the present
invention.
[0019] To assist in the understanding of the embodiments of the
present invention, the following list of components and associated
numbering found in the drawings is provided herein.
TABLE-US-00001 Component # Ground Source Heat Pump System 2 Ground
Loop 6 Heat 10 Ground 14 Cool Fluid 18 Coolant Loop 22 Cold Coolant
Vapor 26 Heat Exchanger 30 Compressor 32 Hot Coolant Vapor 34
Condenser 36 Fan 38 Hot Coolant Liquid 42 Expansion Valve 46
Evaporator 48 Heat Pump 50 Storage Tank 54 Radiant In-Floor Heating
System 58 Ground Loop Manifold 62 Ground Loop First Inlet 64 Ground
Loop Second Inlet 68 Load Loop First Inlet 72 Load Loop Second
Inlet 76 Outlet Load Loop 78 Outlet Ground Loop 80 Check Valve 84
Source Pump 88 Pump 92 Load In 96 Load Out 100 Source In 104 Source
Out 108 Hot Water 112 Cool Water 116 Mixing Tee 120 Warm Water 124
Cold Liquid Coolant 128 Superheated Coolant Vapor 132 First Heat
Exchanger 140 Second Heat Exchanger 144 Mixing Valve 145
Refrigerant Conduit 148 Pump 152 Load Side 156 Source Side 160 Tank
Input 164 Ball Valve 168 Tank Output 170 Temperature Sensor 174
Flow Sensor 178
[0020] It should be understood that the drawings are not
necessarily to scale. In certain instances, details that are not
necessary for an understanding of the invention or that render
other details difficult to perceive may have been omitted. It
should be understood, of course, that the invention is not
necessarily limited to the particular embodiments illustrated
herein.
DETAILED DESCRIPTION
[0021] Referring now to FIGS. 1 and 2, a ground source heat
exchange system 2 of the prior art is shown. More specifically, as
is well understood by one skilled in the art, the prior art heating
system 2 employs a ground loop 6 that is positioned either
horizontally or vertically within the earth surface. The latent
heat 10 of the ground 14 is transferred to the cooler fluid 18 in
the ground loop 6 via heat conduction. The now heated warm fluid 18
in the loop is then placed in thermal communication with a coolant
loop 22 via a heat exchanger 30 wherein the heat from the ground
loop 6 is transferred to coolant contained in the coolant loop 22.
The cold coolant vapor 26 produced by the heat exchanger 30 is then
compressed by a compressor 32, thereby converting
electro-mechanical energy into heat energy that increases the
temperature of the vapor. The now hot vapor 34 is then directed to
a condenser 36 wherein the heat energy may be extracted therefrom
via a fan 38, for example, to heat the inside of a structure. When
the fan 38 removes heat from the coolant, coolant vapor condenses
into hot liquid 42 that is directed to an expansion valve 46 that
decreases the pressure and temperature of the hot liquid 42.
Additionally, one skilled in the art will appreciate that hot
liquid 42 exiting the heat pump 50 may be directed to a storage
tank 54 for use in other hot water applications, such as showers,
dishwashers, etc. and/or be used for radiant in-floor heating
systems 58. As can be seen specifically in FIG. 2, due to the size
and location for the placement of the ground loop 6, it may have to
be placed vertically, wherein expensive drilling is required.
[0022] A ground source heat pump system 2 of the prior art that
employs a plurality of coolant loops is shown in FIG. 1. More
specifically, fluid is circulated via a ground loop 6 that employs
a manifold 62 to split the flow into various loops that are in
contact with the earth. The ground-heated water then is pumped into
another manifold where it is split into a ground loop first inlet
64 and a ground loop second inlet 68, which are both fed into the
heat pump 50. The heat pump 50 employs a heat exchanger (not shown)
that allows the ground loop first inlet 64 and the ground loop
second inlet 68 to exchange their heat with a load loop first inlet
72 and a load loop second inlet 76. The now heated water from the
inlet load first and second loops 72, 76 are expelled via a outlet
load loop 78. Also employed by the heat pump is an outlet ground
loop 80 that directs fluid back into the ground loop 6. The outlet
load loop 78 begins at the heat pump 50 and is directed to a
storage tank 54, wherein a portion thereof is directed to a fan
duct 38 to provide heated air to a structure, for example. Heated
fluid may also be directed to radiant in-floor heating system 58.
Various check valves 84 throughout the system ensure that the fluid
in the system remains in the correct circulatory pattern. One
skilled in the art will appreciate that when the fluid flow through
the system is reversed, the heating system would necessarily become
a cooling system. The fluid that exits the fan coil 38 and the
radiant in-floor heating system 58 is directed to the storage tank
54, thereby allowing for the heat still present in the fluid to be
used again, if necessary. The storage tank 54 also serves as a
reservoir to provide fluid to be used by the inlet load first and
second loops 72, 76.
[0023] Referring now to FIGS. 3 and 4, one embodiment of the
present invention is shown. In the illustrated embodiment, the
ground source loop has been eliminated. More specifically,
embodiments of the present invention include a heat pump with a
"load-in" conduit 96 and a "load-out" conduit 100 along with a
"source-in" 104 conduit and a "source-out" 108 conduit. "Load-in"
96 and "load-out" 100 refers to conduits that supply heated water
from the heat pump 50 to the storage tank 54, a hydronic fan coil
38, and/or in-floor heating devices 58. "Source-in" 104 and
"source-out" 108 refers to conduits that supply warm water to the
heat pump 50. Within the heat pump 50 exists a condenser 36,
expansion valve 46, evaporator 48, and compressor 32 that are
linked together with a conduit that stores a coolant, such as a
refrigerant, a system that substantially similar to that of the
prior art and should be well understood by one skilled in the art.
The major difference between the embodiments of the present
invention and that of the prior art is the source of heat energy
directed to the source-in 104 side of the heat pump 50 is heat
energy that originates from the hot water 112 of the load-out
conduit 100 of the heat pump 50 that has been mixed with water from
the source-out 108 side of the heat pump 50. The advantage of
premixing the source-in 104 water is that the source side of the
system can be pumped through the heat pump 50 at a much slower rate
due to the fact that water of about 92.degree. to 95.degree. F. is
being directed adjacent to the evaporator 46 of the heat pump 50.
More specifically, prior art devices direct water of about
38.degree. F. into the evaporator 46 at a flow rate of about 12-15
gallons per minute, thereby increasing the chance that the coolant
in the evaporator coils 46 freeze. Since embodiments of the present
invention utilize fluid at a much higher temperature, freezing of
the evaporator coils 46 is not an issue such that a smaller and
more efficient source pump 88 may be utilized. One skilled in the
art will appreciate that the system as contemplated herein is not
as efficient as the ground source heat pump system as currently
employed, however, the system is still more efficient than an
air-to-air heat pump system, as described above in outdoor
temperatures that are below about 34.degree..
[0024] In operation, cool water 116 from the storage tank 54 is
pumped into the load-in 96 side of the heat pump 50. As used
herein, "cool" water 116 shall refer to water from temperatures of
about 70.degree. to 110.degree. F. The cool water 116 is heated by
the operation of the heat pump 50 and exits the heat pump 50 at a
temperature of about 5.degree. hotter than it entered the heat pump
50, up to about 115.degree., at a rate of about 12 gallons per
minute (load-out 100). The hot water 112 is then split at a tee 120
wherein a mass flow of about 9 gallons per minute is directed to
the storage tank 54 for future use in hot water applications, such
as washing machines, dishwashers, showers, etc. The 9 gallon per
minute flow may also be pumped into a hydronic fan coil 38 or
in-floor radiant heating system 58 for use in temperature
regulation of a dwelling. Once the heat is transferred from the
water via the fan 38 and/or the in-floor heating system 58, it
returns as cool water 116 into the storage tank 54. It is important
to note that the lines are closed wherein no outside contaminations
would enter the conduit. The loop is completed by a conduit that
runs to a pump 92 that pumps some of the fluid stored in the
storage tank 54 and return fluid from the fan 38 and/or in-floor
heating system 58 conduits at a rate of approximately 12 gallons
per minute to the heat pump 50 (load-in 96).
[0025] The source side of the system is basically the same as a
ground loop side of the prior art however with an important
modification. As stated above, the load-out side 100 of the system
carries water in a conduit at approximately 115.degree. at a rate
of approximately 12 gallons per minute wherein 9 gallons per minute
was directed towards the storage tank 54, fan 38, and in-floor
heating 58, for example. The remaining 3 gallons per minute is
directed to the source-in 104 side of the heat pump 50. More
specifically, the hot water 112 from the load-out side 100 is mixed
with cooler water 116 from the source-out side 108 of the heat pump
50 to supply water from about 92.degree. to 95.degree. F. to the
heat pump 50 (source-in 104). The mixed warm water 124 is pumped at
a rate of about 3 gallons per minute into the heat pump 50 and
supplies the source-in side 104 of the heat pump 50. The source out
108 water exits the heat pump 50 at about 65.degree. at three
gallons per minute, wherein approximately one gallon per minute is
directed to the source in 104 conduit and the remainder is directed
to the storage tank 54, thereby adding to the 9 gallons per minute
that exits the heating fan 38 and/or in-floor heating conduits 58
to produce the about 12 gallons per minute load-in 96 mass
flow.
[0026] Referring now to FIG. 4, the internal componentry of the
heat pump 50 is shown. More specifically, the warm water 124
(source-in 104) is placed in thermal communication with a coolant
in an evaporator 48 of a vapor compression cycle loop. As the cold
liquid coolant 128 interacts with the warm water 124 of the
source-in 104 side, it evaporates to form hot coolant vapor 34 that
is compressed by a compressor 32 and directed as superheated vapor
132 into a condenser 36. The condenser 36 allows for the load-in 96
fluid to thermally communicate with the super-heated vapor 132,
thereby transferring heat from the super-heated vapor 132 into the
load-out fluid 100. After the heat has been extracted from the
super heated coolant vapor 132 it becomes hot liquid coolant 42
that is pumped 88 into the expansion valve 46 that decreases
pressure and temperature and allows the coolant to cool into cold
liquid coolant 128 to complete the cycle. Since some of the heat
associated with the load side of the heating system is being taken
to be mixed into the source-in 104 side, the compressor 32 must add
more energy to the coolant. That is, in order to maintain the fluid
temperature of the load-out side 100 of the heat pump 50,
additional energy must be added via the compressor 32 to the
coolant, to allow the load side of the system to consistently
achieve a temperature of about 115.degree. F.
[0027] Referring now to FIG. 5, another embodiment of the present
invention is shown that includes many of the same components of the
embodiments described above. Here, however, the line directly
connecting the source out conduit 108 to the source in conduit 104
is omitted. More specifically, a system is provided that comprises
a first heat exchanger 140 and a second heat exchanger 144
interconnected by way of a refrigerant conduit 148 in a closed
circuit. The refrigerant conduit 148 also includes a compressor 32
and an expansion valve 46 as described above. A pump 152 may also
be included to facilitate flow of refrigerant through the
refrigerant conduit 148. In one embodiment, the first heat
exchanger 144 is a condenser and the second heat exchanger 148 is
an evaporator.
[0028] The first heat exchanger 144 is associated with the "load
side" 156 of the system that feeds fluid to the first heat
exchanger 140 with a load in conduit 96 and that pulls heated fluid
from the first heat exchanger 140 with a load out conduit 100. The
load side 156 draws heat from the first heat exchanger 140 to reuse
elsewhere in a dwelling, for example. The second heat exchanger 144
is associated with a "source side" 160 of the system which includes
a source in conduit 104 and a source out conduit 108 which provides
the heat that raises the temperature of the refrigerant flowing
within the refrigerant conduit 148 that provides heat to the load
side 156. The load out conduit 100 is also associated with a mixing
tee 120 or other member, such as a mixing valve, that splits the
fluid flowing therein wherein, a portion of the heated fluid is
directed to source in conduit 104 and a majority of the fluid is
directed to an inlet conduit 164 of the storage tank 54. The cool
fluid outputted from the source side 160 is directed to the storage
tank 54 as well. In order to control the flow of fluid within the
source in conduit 104, one embodiment employs a valve, such as a
ball valve 168. A ball valve 168 may also be employed in the source
out conduit 108 to further control the flow of fluid therethrough.
On skilled in the art will appreciate that the terms "mixing valve"
and "ball valve" as used herein shall mean any mechanism used to
split flow, restrict flow or control the flow fluid within a
conduit.
[0029] In operation, in order to initiate flow of the heated water
through the system, at least one pump 92 is initiated.
Concurrently, the pump 152 of the heat pump 150 is initiated,
thereby starting refrigerant flow through the heat pump that
directs refrigerant to the compressor 32 that compresses and thus
heats the refrigerant. The heated refrigerant is then directed to
the first heat exchanger 140 wherein heat is transferred to the
fluid in the load in conduit 96. Heated output fluid is then
directed to the mixing tee 120 and split wherein a majority thereof
is fed to the storage tank 54. Fluid in the storage tank 54 is then
drawn through a storage tank outlet conduit 170 by pumps 92 as
needed to feed a heating fan 38, infloor heating system 58, or
other heating device. Fluid that has been drained of all or some of
its heat from the heating fan 38 and/or infloor heating system 58
is directed to the storage tank 54.
[0030] Again, a portion of the load side 156 output fluid is
directed to the source side 104 of the system and used to feed the
second heat exchanger 144. That heat is used to evaporate the fluid
in the refrigerant conduit 148 to complete the vapor cycle. The
output fluid from the source side 160 is also directed to the
storage tank 54. Fluid from the storage tank 54 is used as the
input fluid of the load side 156.
[0031] In one embodiment of the present invention, the pump 92
pulls water from the storage tank 54 at about 12 gallons/min and
135.degree. Fahrenheit. The temperature of the fluid in the storage
tank is about 140.degree. Fahrenheit. The first heat exchanger 140
raises the temperature of the load side 156 to about 143.degree.
Fahrenheit which flows at about 12 gallons/min within the load out
conduit 100. The flow in the load out conduit 100 is split wherein
about 0.8 gallons/min is directed to the source in conduit 104 with
the remainder being sent to the storage tank 54. Thus, the source
side 160 receives about 143.degree. Fahrenheit fluid. The fluid in
the source out conduit 108 flows at about 0.8 gallons/min at about
61.degree. Fahrenheit. To monitor the performance of one
embodiment, a temperature sensor 174 was associated with the source
side 160 approximate to the ball valve 168 of the source in conduit
104. Additionally, a temperature sensor 174 and a flow sensor 108
were located approximate to an optional ball valve 168 therein. The
load side 156 was also monitored with temperature sensors 174
associated with the load in 96 and load out 100 conduits. Finally,
a flow sensor 178 was associated with the load out conduit 100. For
the test Metrima model svm f27hc sensors were used. The source side
160 sensors measured input power consumption of about 9.7 kilowatts
(33,120 BTU/hr) and the load side sensor 156 measured a power
production of about 14.26 kilowatts (48,690 BTU/hr). The power
consumption of the compressor is about 16.2 amps and the fan 38
produces about a 20 degree temperature increase. One of skilled in
the art will appreciate that the fluid in the system may be water
or any other fluid or gas used for heat transfer. The refrigerant
may be any acceptable fluid. One skilled in the art will also
appreciate that the compressor may be used to supplement any heat
losses in the system by converting electrical energy to additional
heat in the refrigerant line.
[0032] Components of the embodiments of the present invention are
readily obtainable and currently used, thereby making construction
of embodiments of the prior art feasible. For example, in
experiments, conduit made of copper and of 3/4'' and 1/2'' diameter
have been employed for the mixing loop and the source-in 104 loop.
In addition, within the heat pump 50, a pump manufactured by
Grunfoss that produces 0.70 horse power along with a compressor 32
produced by Copeland has been used. The remaining portions of the
water-to-water self-contained heat pump are generally well known in
the art.
[0033] While various embodiments of the present invention have been
described in detail, it is apparent that modifications and
alterations of those embodiments will occur to those skilled in the
art. However, it is to be expressly understood that such
modifications and alterations are within the scope and spirit of
the present invention, as set forth in the following claims.
* * * * *