U.S. patent application number 11/668403 was filed with the patent office on 2007-07-05 for heat pump dehumidification system.
Invention is credited to B. Ryland Wiggs.
Application Number | 20070151280 11/668403 |
Document ID | / |
Family ID | 37863710 |
Filed Date | 2007-07-05 |
United States Patent
Application |
20070151280 |
Kind Code |
A1 |
Wiggs; B. Ryland |
July 5, 2007 |
Heat Pump Dehumidification System
Abstract
A heat pump dehumidification system comprised of one of an air
source heat pump system, a water source heat pump system, and a
direct expansion heat pump system, with an extra interior air heat
exchange means situated between the system's compressor's hot
refrigerant gas discharge side and the exterior heat exchange
means, for activation and use in conjunction with the system's
primary interior air heat exchange means, located between the
exterior heat exchange means and the system's compressor's
refrigerant gas suction side, when operation in a dehumidification
mode is desired absent sensible cooling, and optimum design sizes
for both interior air exchange means while the system is operating
in one of a dehumidification mode, a cooling mode, and a heating
mode.
Inventors: |
Wiggs; B. Ryland; (Franklin,
TN) |
Correspondence
Address: |
WADDEY & PATTERSON, P.C.
1600 DIVISION STREET, SUITE 500
NASHVILLE
TN
37203
US
|
Family ID: |
37863710 |
Appl. No.: |
11/668403 |
Filed: |
January 29, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10815530 |
Apr 1, 2004 |
7191604 |
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11668403 |
Jan 29, 2007 |
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60547979 |
Feb 26, 2004 |
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Current U.S.
Class: |
62/324.1 ;
62/160; 62/176.1 |
Current CPC
Class: |
F25B 30/06 20130101;
F24F 3/14 20130101; F25B 2313/0212 20130101; F25B 13/00 20130101;
F25B 2313/0293 20130101; F25B 2313/0294 20130101; F25B 40/04
20130101; F25B 2313/02741 20130101; F25B 2313/002 20130101; F24F
3/153 20130101 |
Class at
Publication: |
062/324.1 ;
062/160; 062/176.1 |
International
Class: |
F25B 13/00 20060101
F25B013/00; F25D 17/04 20060101 F25D017/04 |
Claims
1. A method of designing one of a heat pump dehumidification system
and an improved efficiency interior air heat exchange means for an
operative heat pump system, which heat pump system is comprised of
at least a refrigerant, refrigerant transport tubing, a compressor,
interior heat exchange means, and exterior heat exchange means,
comprising providing a first interior air heat exchange means to
withdraw heat from the interior air, situated between the system's
exterior heat exchange means and the system's compressor's
refrigerant gas/vapor intake point, and providing a second interior
air heat exchange means to reject heat into the interior air,
situated between the system's compressor's refrigerant gas/vapor
discharge point and the system's exterior heat exchange means.
2. The method of claim 1, where the system's first interior air
heat exchange means, and not the system's second interior air heat
exchange means, is operatively engaged during the system's cooling
mode of operation.
3. The method of claim 2, where the system's second interior air
heat exchange means is operatively disengaged in the cooling mode
of operation by means of at least one of a solenoid valve and a
check valve.
4. The method of claim 1, where the system's first interior air
heat exchange means and the system's second interior air heat
exchange means are both operatively engaged during the system's
dehumidification mode of operation.
5. The method of claim 4, where the cooled interior air, provided
by means of the first interior air heat exchange means, is mixed
with the heated interior air, provided by means of the secondary
interior air heat exchange means, for introduction into the
interior air space.
7. The method of claim 5, where the system's second interior air
heat exchange means is operatively engaged in the dehumidification
mode of operation by means of at least one of a solenoid valve and
a check valve.
8. The method of claim 5, where at least one of the system's
dehumidification mode of operation and the at least one of a
solenoid valve and a check valve is controlled by at least one of a
humidistat and a thermostat.
9. The method of claim 4, where the system's humidistat's call for
operation in the dehumidification mode is subject to, and will not
override, the system's thermostat's call for operation in the
cooling mode.
10. The method of claim 1, where the heat pump system is comprised
of at least one of a direct expansion heat pump system, a water
source heat pump system, and an air source heat pump system.
11. The method of claim 1, where the heat pump system's second
interior air heat exchange means rejects heat into the interior air
at a rate equal to the first interior air heat exchange means, less
the rate equivalent to the additional heat of compression generated
by means of the system's compressor.
12. The method of claim 1, where at least one of the system's
cooling mode of operation and dehumidification mode of operation is
controlled by at least one of a thermostat, a humidistat, and a
thermostat/humidistat combination.
13. The method of claim 1, where both the first interior air heat
exchange means and the second interior air heat exchange means are
respectively comprised of an air handler.
14. The method of claim 13, where both respective air handlers are
comprised of at least one of single speed air handlers, multi-speed
air handlers, and variable speed air handlers, and where both
respective air handlers simultaneously operate at one of a
concurrent desired multiple cubic feet per minute airflow speed,
less the rate in the second interior air heat exchange means that
is equivalent to the additional heat of compression generated by
means of at least one of the system's compressor and externally
powered components.
15. The method of claim 13, where the heat pump system's compressor
is at least one of a single speed compressor, a multiple speed
compressor, and a variable speed compressor, and where both
respective air handlers operate at one of a concurrent desired
lower speed when the compressor is operating at a lower speed, less
the rate in the second interior air heat exchange means that is
equivalent to the additional heat of compression generated by means
of at least one of the system's compressor and externally powered
components, and where both respective air handlers operate at one
of a concurrent desired higher speed when the compressor is
operating at a higher speed, less the rate in the second interior
air heat exchange means that is equivalent to the additional heat
of compression generated by means of at least one of the system's
compressor and externally powered components.
16. The method of claim 13 where the first air handler's tonnage
capacity is designed at a tonnage design capacity that is greater
than the system's maximum compressor tonnage design capacity, and
where the second air handler's tonnage capacity is designed at a
tonnage design capacity that is one of equal to and less than the
system's maximum compressor tonnage design capacity.
17. The method of claim 13 where the first air handler's tonnage
capacity is designed at 200%, plus or minus 10% of 100%, of the
system's maximum compressor tonnage design capacity, and where the
second air handler's tonnage capacity is designed at 100%, plus or
minus 10% of 100%, of the system's maximum compressor tonnage
design capacity.
18. The method of claim 13 where the system's first air handler is
one of by-passed, by means of a refrigerant transport tube, and is
deactivated/disengaged, and is deactivated/disengaged by means of
deactivating the first air handler's fan and reducing the first air
handler's CFM airflow, while the system's second air handler is
engaged and operative and the system is operating in the heating
mode.
19. A heat pump dehumidification system and an improved efficiency
interior air heat exchange means for an operative heat pump system,
which heat pump system is comprised of at least a refrigerant,
refrigerant transport tubing, a compressor, interior heat exchange
means, and exterior heat exchange means, comprising providing a
first interior air heat exchange means to withdraw heat from the
interior air, situated between the system's exterior heat exchange
means and the system's compressor's refrigerant gas/vapor intake
point, and providing a second interior air heat exchange means to
reject heat into the interior air, situated between the system's
compressor's refrigerant gas/vapor discharge point and the system's
exterior heat exchange means.
20. The system of claim 19, where the system's first interior air
heat exchange means, and not the system's second interior air heat
exchange means, is operatively engaged during the system's cooling
mode of operation.
21. The system of claim 20, where the system's second interior air
heat exchange means is operatively disengaged in the cooling mode
of operation by means of at least one of a solenoid valve and a
check valve.
22. The system of claim 20, where at least one of the system's
cooling mode of operation and the at least one of a solenoid valve
and a check valve is controlled by at least one of a thermostat and
a humidistat.
23. The system of claim 19, where the system's first interior air
heat exchange means and the system's second interior air heat
exchange means are both operatively engaged during the system's
dehumidification mode of operation.
24. The system of claim 23, where the cooled interior air, provided
by means of the first interior air heat exchange means, is mixed
with the heated interior air, provided by means of the secondary
interior air heat exchange means, for introduction into the
interior air space.
25. The system of claim 23, where the system's second interior air
heat exchange means is operatively engaged in the dehumidification
mode of operation by means of at least one of a solenoid valve and
a check valve.
26. The system of claim 23, where at least one of the system's
dehumidification mode of operation and the at least one of a
solenoid valve and a check valve is controlled by at least one of a
humidistat and a thermostat.
27. The systems of claim 22, where the system's humidistat's call
for operation in the dehumidification mode is subject to, and will
not override, the system's thermostat's call for operation in the
cooling mode.
28. The system of claim 19, where the heat pump system is comprised
of at least one of a direct expansion heat pump system, a water
source heat pump system, and an air source heat pump system.
29. The system of claim 19, where the heat pump system's second
interior air heat exchange means rejects heat into the interior air
at a rate equal to the first interior air heat exchange means, less
the rate equivalent to the additional heat of compression generated
by means of the system's compressor.
30. The system of claim 19, where at least one of the system's
cooling mode of operation and dehumidification mode of operation is
controlled by at least one of a thermostat, a humidistat, and a
thermostat/humidistat combination.
31. The system of claim 19, where both the first interior air heat
exchange means and the second interior air heat exchange means are
respectively comprised of an air handler.
32. The system of claim 31, where both respective air handlers are
comprised of at least one of single speed air handlers, multi-speed
air handlers, and variable speed air handlers, and where both
respective air handlers simultaneously operate at one of a
concurrent desired multiple cubic feet per minute airflow speed,
less the rate in the second interior air heat exchange means that
is equivalent to the additional heat of compression generated by
means of at least one of the system's compressor and externally
powered components.
33. The system of claim 31, where the heat pump system's compressor
is at least one of a single speed compressor, a multiple speed
compressor, and a variable speed compressor, and where both
respective air handlers operate at one of a concurrent desired
lower speed when the compressor is operating at a lower speed, less
the rate in the second interior air heat exchange means that is
equivalent to the additional heat of compression generated by means
of at least one of the system's compressor and externally powered
components, and where both respective air handlers operate at one
of a concurrent desired higher speed when the compressor is
operating at a higher speed, less the rate in the second interior
air heat exchange means that is equivalent to the additional heat
of compression generated by means of at least one of the system's
compressor and externally powered components.
34. The system of claim 31 where the first air handler's tonnage
capacity is designed at a tonnage design capacity that is greater
than the system's maximum compressor tonnage design capacity, and
where the second air handler's tonnage capacity is designed at a
tonnage design capacity that is one of equal to and less than the
system's maximum compressor tonnage design capacity.
35. The system of claim 31 where the first air handler's tonnage
capacity is designed at 200%, plus or minus 10% of 100%, of the
system's maximum compressor tonnage design capacity, and where the
second air handler's tonnage capacity is designed at 100%, plus or
minus 10% of 100%, of the system's maximum compressor tonnage
design capacity.
36. The system of claim 31 where the system's first air handler is
one of by-passed, by means of a refrigerant transport tube, and is
deactivated/disengaged, and is deactivated/disengaged by means of
deactivating the first air handler's fan and reducing the first air
handler's CFM airflow, while the system's second air handler is
engaged and operative and the system is operating in the heating
mode.
37. The method of claim 3, where at least one of the system's
cooling mode of operation and the at least one of a solenoid valve
and a check valve is controlled by at least one of a thermostat and
a humidistat.
38. The method of claim 7, where at least one of the system's
dehumidification mode of operation and the at least one of a
solenoid valve and a check valve is controlled by at least one of a
humidistat and a thermostat.
39. The method of claim 8, where the system's humidistat's call for
operation in the dehumidification mode is subject to, and will not
override, the system's thermostat's call for operation in the
cooling mode.
40. The system of claim 21, where at least one of the system's
cooling mode of operation and the at least one of a solenoid valve
and a check valve is controlled by at least one of a thermostat and
a humidistat.
41. The system of claim 25, where at least one of the system's
dehumidification mode of operation and the at least one of a
solenoid valve and a check valve is controlled by at least one of a
humidistat and a thermostat.
42. The systems of claim 26, where the system's humidistat's call
for operation in the dehumidification mode is subject to, and will
not override, the system's thermostat's call for operation in the
cooling mode.
Description
APPLICATION FOR UNITED STATES LETTERS PATENT
[0001] This application claims priority to co-pending U.S. patent
application Ser. No. 10/815,530 filed May 5, 2004, entitled "Heat
Pump Dehumidification System", which claims priority to U.S. Patent
Application Ser. No. 60/547,979 filed Feb. 26, 2004, entitled "Deep
Well Direct Expansion System Dehumidifier", both of which are
hereby incorporated by reference in their entireties.
[0002] A portion of the disclosure of this patent document contains
material that is subject to copyright protection. The copyright
owner has no objection to the facsimile reproduction by anyone of
the patent document or the patent disclosure, as it appears in the
Patent and Trademark Office patent file or records, but otherwise
reserves all copyright rights whatsoever.
[0003] Be it known that I, B. Ryland Wiggs, a citizen of the United
States, residing at 425 Sims Lane, Franklin, Tenn. 37069, have
invented a new and useful "Heat Pump Dehumidification System."
BACKGROUND OF THE INVENTION
[0004] The present invention relates to an improved heat pump
dehumidification system, consisting of at least one of an air
source heat pump, a water source heat pump, and a direct expansion
heat pump, incorporating a unique combination of an additional
interior heat exchange means (typically an air handler) for use
when the system has satisfied the thermostat setting in the cooling
mode of operation, but when humidity levels remain excessively
high, as well as an optimum design sizing for a heat pump system's
interior air heat exchange means while operating in one of a
dehumidification mode, a cooling mode, and a heating mode.
[0005] Air source heat pump systems typically circulate a
refrigerant, such as R-22 or the like, as a means to extract heat
from the exterior air in the heating mode of operation, and as a
means to reject heat into the exterior air in the cooling mode of
operation. An electric fan typically enhances the circulation of
air over a first array of exterior finned heat exchange tubing
exposed to the exterior air. Having gained heat from, or rejected
heat into, the exterior air, the heated or cooled refrigerant is
then circulated, by means of a refrigerant compressor, through the
refrigerant transport tubing into a second array of finned heat
exchange tubing, with airflow augmented by means an electric fan,
located within the interior space, with a second heat exchange step
comprising a transfer of heat to or from the refrigerant to heat or
cool interior air space, depending on the direction of the flow of
refrigerant in the heating mode or in the cooling mode. The
operation of an air source heat pump is well understood by those
skilled in the art.
[0006] Rather than using exterior air as an exterior heat exchange
means, ground source/water source heat pump systems typically
utilize fluid-filled closed loops of tubing buried in the ground,
or submerged in a body of water, so as to either absorb heat from,
or to reject heat into, the naturally occurring geothermal mass
and/or water surrounding the buried or submerged tubing.
Water-source heating/cooling systems typically circulate, via a
water pump, water, or water with anti-freeze, in plastic
underground geothermal tubing so as to transfer heat to or from the
ground, with a second heat exchange step utilizing a refrigerant,
such as R-22 or the like, to transfer heat to or from the water,
and with a third heat exchange step utilizing an array of interior
finned refrigerant transport tubing, with airflow augmented by an
electric fan, to transfer heat to or from the refrigerant to heat
or cool interior air space. The operation of a water source heat
pump is well understood by those skilled in the art.
[0007] Direct eXpansion (herein referred to as "DX") ground source
systems, where the refrigerant transport lines are placed directly
in the sub-surface ground and/or water, typically circulate a
refrigerant fluid, such as R-22, in sub-surface refrigerant lines,
typically comprised of copper tubing, to transfer heat to or from
the sub-surface elements, and only require a second heat exchange
step to transfer heat to or from the interior air space by means of
the interior air's exposure to an array of finned heat transfer
tubing, with the interior's air flow augmented by an electric
fan.
[0008] Consequently, DX systems are generally more efficient than
water-source systems because of less heat exchange steps and
because no water pump energy expenditure is required. Further,
since copper is a better heat conductor than most plastics, and
since the refrigerant fluid circulating within the copper tubing of
a DX system generally has a greater temperature differential with
the surrounding ground than the water circulating within the
plastic tubing of a water-source system, generally, less excavation
and drilling is required, and installation costs are generally
lower with a DX system than with a water-source system.
[0009] Also, since DX systems do not require a defrost cycle in the
heating mode, and since the sub-surface geothermal heat exchange
temperatures are far more stable than those of widely fluctuating
exterior air in ever-changing atmospheric conditions, DX systems
are generally more efficient than air source systems.
[0010] While most in-ground/in-water heat exchange designs are
feasible, various improvements have been developed intended to
enhance overall system operational efficiencies in DX heat pumps.
Various such design improvements are taught in U.S. Pat. No.
5,623,986 to Wiggs; in U.S. Pat. No. 5,816,314 to Wiggs, et al.; in
U.S. Pat. No. 5,946,928 to Wiggs; in U.S. Pat. No. 6,615,601 B1 to
Wiggs; in Wiggs' U.S. patent application Ser. No. 10/073,513; in
Wiggs' U.S. patent application Ser. No. 10/127,517; in Wiggs' U.S.
patent application Ser. No. 10/251,190; in Wiggs' U.S. patent
application Ser. No. 10/335,514; in Wiggs' U.S. patent application
Ser. No. 10/616,701, in Wiggs' U.S. patent application Ser. No.
10/757265, and in Wiggs's U.S. patent application Ser. No.
10/804,698, the disclosures of which are incorporated herein by
reference.
[0011] Since DX heat pump applications are generally the most
efficient types of heat pumps, and since the interior air heat
exchange means is basically the same for all heat pump systems,
only the best heat pump design will be demonstrated herein,
although the subject invention can be utilized in an identical
manner for all heat pump systems, whether air source, water source
or DX.
[0012] Virtually all heat pump systems utilize a compressor, an
interior heat exchange means, an exterior heat exchange means,
thermal expansion devices, an accumulator, a refrigerant fluid
(such as R-22, R-410A, or the like), and operatively connected
refrigerant transport tubing, as is well understood by those
skilled in the art. Also, most all heat pump systems utilize an
interior air handler, comprised of an array of finned refrigerant
transport tubing with airflow augment by an electric fan, as the
interior heat exchange means, as is well understood by those
skilled in the art. However, occasionally, the interior heat
exchange means may be comprised of a refrigerant to water heat
exchange means, with the water circulated within the interior
space, which is commonly referred to as a hydronic type interior
heat exchange means, as is well understood by those skilled in the
art.
[0013] As explained, virtually all heat pump systems utilize an
array of finned refrigerant transport tubing, with the interior
airflow passing over same augmented by means of an electric fan,
which is commonly referred to as an air handler. As the interior
air passes over the finned tubing, the air absorbs heat from the
hot refrigerant in the heating mode, and rejects heat into the cold
refrigerant in the cooling mode. The air handler may be comprised
of one or multiple sets of arrays of finned refrigerant transport
tubing, and the air handler's electric fan may be designed to
operate at one or at multiple speeds. All of this is well
understood by those skilled in the trade.
[0014] While virtually all heat pump systems operate in a
reverse-cycle mode, and may be switched from a heating mode to a
cooling mode, and vice versa, by simply changing the setting on the
system's thermostat, as is well understood by those skilled in the
art, the present invention is principally concerning the operation
of heat pump systems in the cooling mode.
[0015] When operating in the cooling mode, cold refrigerant is
circulated through the interior air handler, with the warmer
interior air being blown over the cold finned refrigerant transport
tubing by means of an electric fan. Heat is absorbed by the cold
refrigerant, as heat always travels to cold, and is thereby removed
from the interior air. The removal of heat is commonly referred to
as the sensible load work performed by the system. However, in the
cooling mode of operation, a second consequence of the heat pump's
operation occurs. Namely, naturally occurring moisture in the
interior air is also removed. This removal of moisture, which is
commonly referred to as the latent load work performed by the
system, results because the cold refrigerant is below the dewpoint.
Consequently, when operating in the cooling mode, all heat pump
systems' interior heat exchange means are equipped with a moisture
condensate drain to remove the condensed moisture from the interior
space. Typically, the condensate drain consists of a PVC tube, or
the like, which typically simply carries the water to the exterior
of the house via gravity. If the condensate water must travel
uphill to be removed, such as from a basement area, a small
condensate water pump, electrically operated, is situated at a low
point within the condensate drain line to pump the water out of the
structure. All of the above is well understood by those skilled in
the art, and consequently, the condensate drain is not shown
herein.
[0016] In many areas, excessive moisture can create health
concerns, such as fostering molds and dust mites, as well as
decreasing comfort levels. While heat pump systems do remove
moisture from the interior air when operating in the cooling mode,
as explained above, heat pump systems do not remove moisture from
the air when the thermostat is satisfied and the system is
inoperative, as heat pump systems are virtually always solely
designed to provide thermostatic sensible load comfort levels
without regard to interior latent load humidity levels. The removal
of excessive interior humidity has simply been an historical
advantageous by-product of the heat pump system while it is
operating in the cooling mode.
[0017] In areas where high humidity levels can cause discomfort
and/or associated health concerns from mold accumulation and the
like, the removal of high levels of humidity is desirous. It is
reported that data released by the American Society of Heating,
Refrigerating and Air-Conditioning Engineers ("ASHRAE") suggests
that maintaining relative humidity levels between 30% and 60%
limits the harmful effects of many unwanted bacteria, viruses,
fungi, mites, allergic rhinitis and asthma, and other respiratory
related conditions. It is reported that The Journal of Allergy and
Clionical Immunology has recommended that interior relative
humidity levels be maintained below 51% to inhibit dust mites and
to improve healthfulness.
[0018] While all refrigerant based heat pump cooling equipment
generally removes humidity, the cooler the refrigerant the more
humidity that is removed. However, historically, as explained,
humidity is only removed when the heat pump's cooling system is
operating. When the system's thermostat setting is reached,
typically at about 70 degrees F, the cooling system typically shuts
off until the interior air warms enough to register at the
thermostat and to thereby re-engage the cooling system. When the
cooling system is shut off, the system's compressor and interior
air handler both are typically shut off, thereby stopping both the
sensible cooling of the interior air and the associated latent load
removal of interior air humidity, as there is no air flow over the
cold refrigerant within the finned heat exchange tubing of the
interior air handler.
[0019] In order to continuously remove humidity with conventionally
designed systems, one must continuously operate the system in the
cooling mode. Such continuous operation typically results in
excessive cooling, to the point of being uncomfortably cold. While
one could continuously operate a small cooling system in an effort
to continuously remove humidity, and engage a larger cooling system
only when the small unit could not remove the interior heat load,
during cooler nighttime periods even the small cooling system could
still make the interior space uncomfortably cold. Further, smaller
systems may not have the ability to remove large amounts of
humidity present when the primary larger cooling system is shut
off.
[0020] Historically, excessive humidity levels are addressed by the
utilization of a dehumidifier, which dehumidifier is a system
totally separate and independent of a heat pump system, as is well
understood by those skilled in the trade. However, traditional
dehumidifiers are not particularly efficient to operate, require
additional space, do not have the typically higher design load
capacities of heat pump systems, and often require the owner to
manually dispose of trays of accumulated water.
[0021] Since excessively high humidity levels can be both
uncomfortable as well as a health concern, particularly with the
requisite introduction of certain quantities of fresh air into
schoolrooms and the like, a means to utilize existing heat pump
systems to expressly remove excessive humidity, exclusive of the
thermostat level, and without the need to operate a totally
separate and independent dehumidification system is desirable.
[0022] Thus, it is an objective of this subject invention to
disclose a means to utilize existing heat pump systems for
dehumidification purposes, exclusive of the need to obtain and
operate a separate and independent dehumidification system, and
exclusive of the need to solely rely upon heat pump system
operation in the cooling mode controlled by a thermostat.
SUMMARY OF THE INVENTION
[0023] It is an object of the present invention to further enhance
and improve the humidity removal qualities of predecessor heat pump
system designs by means of teaching the addition of a secondary
interior air heat exchange means, designed to neutralize the
thermostatic cooling effect of a heat pump system operating in the
cooling mode once the thermostat's cooling set point has been
satisfied, while simultaneously allowing the heat pump system to
operate and to remove excessive humidity based upon desired
humidistat control settings. Thus, a heat pump dehumidification
system is disclosed comprised of one of an air source heat pump
system, a water source heat pump system, and a direct expansion
heat pump system, with an extra interior air heat exchange means
situated between the system's compressor's hot refrigerant gas
discharge side and the exterior heat exchange means, for activation
and use in conjunction with the system's primary interior air heat
exchange means, located between the exterior heat exchange means
and the system's compressor's refrigerant gas suction side, when
operation in a dehumidification mode is desired absent sensible
cooling.
[0024] Refrigerant system design components are all operatively
connected via refrigerant transport tubing, as is well understood
by those skilled in the art. Virtually all heat pump systems
described herein are electrically powered. Electrical power lines
and electrical connections are not shown herein as they are well
understood by those skilled in the art. All refrigerant transport
tubing referenced is sized for refrigerant grade copper tubing,
which sizing/dimensions are well understood by those skilled in the
art. All calculations of cooling loads are made via conventional
ACCA Manuel J load calculations, or other similar conventional load
design criteria. Cooling load designs are typically calculated in
tonnage design capacities, where 12,000 BTUs equal one ton of
design capacity. ACCA Manuel J heating/cooling load calculations
are well understood by those skilled in the art.
[0025] Virtually all heat pump systems are comprised of at least a
refrigerant, refrigerant transport tubing, a compressor, interior
heat exchange means, and exterior heat exchange means, as is well
understood by those skilled in the art. Additionally, virtually all
heat pump systems are additionally comprised of refrigerant
expansion valves, check vales, an accumulator, an optional
receiver, an optional oil separator, sight glasses, and the like,
as is additionally well understood by those skilled in the art.
[0026] As has been disclosed in the aforesaid Wiggs' U.S. patent
application Ser. No. 10/757,265, which application is incorporated
herein by reference, a highly efficient means of geothermal heating
and cooling was taught.
[0027] Testing has also shown that, when operating in the cooling
mode, the said DX system removes significantly more humidity than
other conventional cooling systems because the refrigerant, being
cooled in the approximate 55 degree F earth, is cooler and further
below the dew-point than the refrigerant being cooled by other
means, such as by 70 degree F to 100 degree F outdoor air in an
air-source heat pump for example. Further, unlike most other
conventional heat pump designs, which are well understood by those
skilled in the art, DX heat pump systems are capable of maintaining
humidity levels below 50%. Thus, while the subject invention may be
utilized in conjunction with any heat pump system, use of the
subject invention in conjunction with a DX system design is shown
herein, as this would render the best preferred results.
[0028] To take advantage of the highly efficient refrigerant
cooling properties of a DX heat pump system, as well as to take
advantage of the cooling properties of any heat pump system, as a
sole means of humidity removal, a means of removing unwanted
humidity must be found which would permit continued operation of
the DX or other heat pump system once the desired cooling
thermostat setting has been reached, all without excessively
cooling the interior air. Such a means may be accomplished by
rejecting all, or a significant portion, of the heat removed by the
heat pump system, when operating in the cooling mode, back into the
interior air instead of into one of the ground (with a DX system),
water circulated in the ground (with a water-source system), and
air (with an air source system), by means of a secondary interior
heat exchange means (typically an air handler) located on the hot
gas refrigerant side of the compressor, prior to the exterior heat
exchange means, when the system is operating in the cooling
mode.
[0029] Thus, the airflow may be continuously maintained over the
cold refrigerant tubing within the heat pump system's primary
interior air handler, located between the system's exterior heat
exchange means and the compressor's suction intake side, thereby
condensing and removing humidity from the interior air, all while
the interior air maintains a relatively constant temperature by
means of the heat, which has been removed from the interior air via
refrigerant circulating within the primary air handler, being
rejected back into the interior air by means of the supplemental
and secondary interior air heat exchange means (typically an air
handler) situated on the hot vapor gas refrigerant discharge side
of the compressor prior to the system's exterior heat exchange
means.
[0030] More specifically, to accomplish this means of removing
humidity once the heat pump system's thermostat setting has been
reached, a secondary interior air handler would be placed within
the refrigerant transport loop at a location between the system's
compressor and one of the sub-surface heat exchange tubing, the
refrigerant to circulating water to ground heat exchange loop, and
the exterior air heat exchange loop, so as to transfer all or most
of the heat removed by the first and primary cooling mode air
handler back into the interior air before the heat is rejected into
the exterior heat exchange means, which is comprised of one of the
earth, water, and exterior air. The warmed air supplied by the
secondary and additional air handler would temper the otherwise
cooled air traveling through the return air ducts, so as to permit
the system to remain in operation without cooling the interior air
to so low a point as to call for the thermostat to become
uncomfortably cool. Preferably, the cooled air and the warmed air
would be mixed together within the supply ductwork, which is well
understood by those skilled in the art, prior to the supply air
being distributed into the interior air space by the supply air
ducts. Further, since all or most (most means all, less the extra
heat generated by means of the externally powered system
components, such as the compressor, the fans, and the like) of the
removed interior air heat is being replaced back into the interior
air before it reaches at least one of the ground and the water in a
geothermal system application, there is no undue heat load or
stress placed upon the sub-surface heat exchange area or upon a
geothermal heat pump system by means of an extended system
operation in the dehumidification mode.
[0031] Generally, the operation of the heat pump system in the
dehumidification mode can be accomplished by means of at least one
of a thermostat and a humidistat, which either activates solenoid
valves to direct refrigerant fluid through the secondary interior
air heat exchange means (air handler), or, absent the existence of
solenoid valves controlling the flow of refrigerant fluid through
one of the air handler and an air handler by-pass refrigerant
transport line when dehumidification mode operation is not desired,
activates the fan in the secondary air handler. The manner of
wiring one of a thermostat and a humidistat so as to operate one of
solenoid valves and a fan motor is well understood by those skilled
in the art.
[0032] While a standard sized DX system could be continuously
operated in a dehumidification mode, even after the thermostat
called for the primary cooling mode to shut off, by means of
engaging the secondary air handler via solenoid valves (solenoid
valves are well understood by those skilled in the art) or the
like, such a continuous operation of the primary DX system
compressor would likely be unnecessary in most situations since
operation of the full heat pump system in a dehumidification mode
will remove far more humidity in much less time than conventional
and smaller dehumidifiers.
[0033] Desirable dehumidification mode system operation can be
controlled by a humidity sensor in a manner similar to that of a
thermostat controlling temperature levels. Thus, if the thermostat
was satisfied and the primary cooling system was not in operation
(thereby normally ceasing to automatically remove humidity), but
the humidity level remained at an unacceptably high level, the
humidity sensor would engage the heat pump system in the
dehumidification mode only, meaning the primary system would now
fully operate in conjunction with the secondary air handler,
restoring the removed sensible heat back into the interior air
supply ducts, until a satisfactory humidity level was reached, at
which point the entire system would shut off.
[0034] In heat pump systems with one of a single speed, a multiple
speed, and a variable speed compressor, at least one of the
thermostat and the humidity sensor (the humidity sensor is also
called the "humidistat") would control the operation of the
compressor at one of the desired speed(s), depending on the desired
level of operation and upon the excessive amount of humidity
present in the interior air. Similarly, the fans in both the
primary and the secondary air handlers would be adjusted to
automatically match the operational speed of the compressor at one
of the available desired fan speed settings to effect the desired
cubic feet per minute of airflow and corresponding desired level of
heat exchange, as is well understood by those skilled in the
art.
[0035] The secondary air handler should be sized to remove all the
heat extracted from the interior air by the primary air handler
operating in the cooling mode so as to maintain a neutral interior
air temperature, with the additional heat generated by the
operation of the system's compressor and fans still being rejected
into the exterior heat exchange means comprised of one of the
ground heat sink, the water to ground heat sink, and the exterior
air heat sink. The rejection of such a minimal amount of system
mechanical operational heat will not impose any undue stress upon a
geothermal system's sub-surface heat exchange field, will not
impose any stress upon an air source system's exterior air heat
exchange means, and will prevent the interior air from becoming too
warm too soon.
[0036] The subject humidity removal design may be utilized with any
geothermal DX system, with any geothermal water-source system, and
with any air source heat pump system, although as stated, due to
the typically colder refrigerant levels produced in the cooling
mode by a DX system, the utilization of a DX system would typically
be preferable. The colder the refrigerant in the cooling mode, the
further the refrigerant temperature is below the dewpoint, and the
greater the ability to efficiently remove excessive interior
humidity. While most air source and water source heat pumps can be
limited to a maintenance of humidity levels at 50%, or greater, a
properly sized/designed DX system, due to its greater geothermal
heat exchange temperature differential, can typically maintain
humidity levels below 50%. Therefore, as stated, a DX heat pump
system dehumidification system is generally preferred.
[0037] To effect an operational heat pump system, customary heat
pump refrigerant system apparatus and materials would be utilized,
such as a compressor, a refrigerant, refrigerant transport tubing,
an accumulator, an optional receiver, an optional oil separator, a
reversing valve to change the direction of the refrigerant flow
(except through the accumulator and compressor) when a
reverse-cycle system is switched from a heating mode to a cooling
mode and vice versa, distributors when multiple refrigerant
transport lines are utilized, a thermostat, wiring, controls,
refrigerant tube couplings, check valves, optional solenoid valves,
sight glasses, filter dryers, above-ground refrigerant transport
line insulation (such as rubatex, or the like), a power source, a
thermostat, and the like, all of which are well-known to those
skilled in the art and therefore are not necessarily all shown
herein. Both the operation and use of a thermostat and a
humidistat, as well as their respective wiring, as well as the
operation and use of a combined thermostat/humidistat and its
wiring, to respectively control the operation of a cooling system
and of a dehumidification system are well understood by those
skilled in the art and are not shown herein. An example of a
combined thermostat/humidistat capable of controlling the subject
heat pump dehumidification system invention is a
thermostat/humidistat model number IF95-391, manufactured by White
Rogers, of 9797 Revis Road, Affton, Mo. 63123.
[0038] There is an additional advantage of utilizing a secondary
interior air heat exchange means (second air handler) for optional
dehumidification purposes. Namely, the incorporation of the second
air handler in the hot gas line enables one to downsize the second
air handler so as to gain warmer air in the heating mode, and
simultaneously enables one to upsize the first and primary interior
air heat exchange means (first air handler) so as to gain cooler
air in the cooling mode and so as to remove more humidity in the
dehumidification mode. Typically, in a reverse-cycle heat pump
application, the standard one air handler is sized somewhere
between the smaller heating mode optimum size and the larger
cooling mode optimum size, so as to reasonably accommodate both
operational modes.
[0039] For optimum system operational designs in most all heat pump
systems, the first interior air heat exchange means, utilized for
cooling mode operation (the first air handler), should be sized at
a design capacity that is larger than the compressor design
capacity, and typically preferably sized at 200%, plus or minus 10%
of 100%, of the maximum compressor tonnage design capacity; and the
second interior air heat exchange means, utilized for heating mode
operation (the second air handler), should be sized at a design
capacity that is equal to, or less than, the compressor design
capacity, and typically preferably sized at 100%, plus or minus 10%
of 100%, of the maximum compressor tonnage design capacity.
[0040] When operating in the dehumidification mode with a first air
handler that is about twice the size of the second air handler, the
airflow over both air handlers must still be equalized, less the
rate in the second interior air heat exchange means (the second air
handler) that is equivalent to the additional heat of compression
generated by means of at least one of the system's compressor and
externally powered components. The multiple manners of equalizing
the airflow over both air handlers is well understood by those
skilled in the art, and may, for one example, be easily
accomplished by decreasing the fan speed, and resulting cubic feet
per minute ("CFM") airflow, of the first air handler so as to match
the desired CFM rate of the second air handler.
[0041] In such an enhanced cooling/dehumidification/heating mode
operational system design, which is enabled by means of adding a
secondary air handler in the manner as herein described, and where
the second air handler is sized at about 50% of the first air
handler, a secondary by-pass refrigerant transport line is
preferably added around the first air handler for use in the
heating mode of operation. The secondary by-pass line is operated
by means of solenoid valves, or the like. A first solenoid valve,
for example, is located prior to the refrigerant flowing through
the self-adjusting thermal expansion device prior to the first air
handler, and is in the open position so as to permit system
operation in one of the cooling mode and the dehumidification mode.
A second solenoid valve, located after the refrigerant has exited
the first air handler, is in a closed position so as to prevent
system operation in the heating mode. A control connecting wire,
for example, connects the control box (the control box is comprised
of a thermostat and a humidistat) with the open first solenoid
valve; and a control connecting wire, for example, connects the
control box with the closed second solenoid valve. As is well
understood by those skilled in the art, one reversing valve, or the
like, can be substituted for the two solenoid valves with the same
effect of by-passing the desired air handler for system operation
in one of the cooling mode and heating mode, or of not by-passing
either air handler, for operation in the dehumidification mode.
Also, the first air handler may be one of completely and mostly
by-passed, while the system is operating in the heating mode, by
various other alternative means other than by means of solenoid
valves and a by-pass refrigerant transport line, as are well
understood by those skilled in the art, such as, for example, by
disengaging the first air handler's fan and thereby materially
reducing the heat transfer over the first air handler's finned
tubing.
BRIEF DESCRIPTION OF THE DRAWINGS
[0042] There are shown in the drawings embodiments of the invention
as presently preferred. It should be understood, however, that the
invention is not limited to the precise arrangements and
instrumentalities shown.
[0043] FIG. 1 is a side view of a deep well direct expansion heat
pump system operating in the dehumidification mode, comprised of a
compressor, a refrigerant (not shown as a refrigerant fluid flowing
within the system is well understood by those skilled in the art),
refrigerant transport lines, two interior air heat exchange means
comprised of a first air handler and a second air handler, an
exterior heat exchange means, and other system components common to
a deep well direct expansion heat pump system.
[0044] FIG. 2 is a side view of ductwork from both interior air
handlers combining so as to mix the cooled and heated air, thereby
neutralizing the cooling effect, prior to distribution into the
interior air space by means of supply air ducts (not shown herein
as supply air ducts are well understood by those skilled in the
art).
[0045] FIG. 3 is a side view of a deep well direct expansion heat
pump system operating in the dehumidification mode, comprised of a
compressor, a refrigerant (not shown as a refrigerant fluid flowing
within the system is well understood by those skilled in the art),
refrigerant transport lines, two interior air heat exchange means
comprised of a first air handler and a second air handler, an
exterior heat exchange means, and other system components common to
a deep well direct expansion heat pump system. In this example, the
second air handler is sized at 50% of the first air handler to
enhance both heating and cooling mode operation efficiencies, and a
by-pass refrigerant line is added around the first air handler for
use in the heating mode of operation.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0046] The following detailed description is of the best presently
contemplated mode of carrying out the invention. The description is
not intended in a limiting sense, and is made solely for the
purpose of illustrating the general principles of the invention.
The various features and advantages of the present invention may be
more readily understood with reference to the following detailed
description taken in conjunction with the accompanying
drawings.
[0047] Referring now to the drawings in detail, where like numerals
refer to like parts or elements, there is shown in FIG. 1 a side
view of a simple version of a deep well direct expansion geothermal
heat pump system, operating in a dehumidification mode.
[0048] A refrigerant fluid (not shown) is transported, by means of
a compressor's 1 force and suction, throughout the system and
to/from various system components by means of refrigerant transport
tubing 2. The directional flow of the refrigerant fluid within the
refrigerant transport tubing 2 is shown by arrows 3 within the
tubing 2.
[0049] The refrigerant flows from the compressor 1 through an oil
separator 4, through an open first solenoid valve 5, and then
through the secondary interior air heat exchange means (secondary
air handler with finned tubing) 6, where most of the heat within
the refrigerant fluid is transferred back into the interior air
(not shown). In the cooling only mode of operation, and not in the
dehumidification mode, the first solenoid vale 5 would be closed
(not shown here as closed) and the refrigerant would flow through
the by-pass line 7 and around the secondary air handler with finned
tubing 6, and through the second solenoid valve 8, which is
alternately shown here in a closed position so as to reflect
dehumidification mode operation. In an alternative means of cooling
only mode of operation, the first and second solenoid valves, 5 and
8, and the by-pass refrigerant transport line 7 could be entirely
eliminated and the secondary air handler's 6 fan 9 could simply be
disengaged, with no electrical power supplied to operate it,
thereby preventing any material airflow through the ductwork 10
containing the secondary air handler 6.
[0050] The refrigerant next flows through the system's reversing
valve 11, and down into the sub-surface geothermal exterior heat
exchange means 12. Exiting the exterior heat exchange means 12,
which has absorbed the minor amount of heat generated by the
system's compressor 1 and fan 9, the refrigerant flows past a pin
restrictor expansion device 13, for use in the heating mode of
operation, through an open check valve 14, through a receiver 15,
and through a self-adjusting thermal expansion device 16. The
refrigerant then flows through the system's primary and first
interior air heat exchange means (first air handler) 17, where the
interior air is sensibly cooled and where latent load humidity is
removed. The condensed humidity is drained away by means of a
condensate drain line 18.
[0051] Lastly, the refrigerant flows from the primary and first air
handler 17, through the reversing valve 11, past the oil return
line from the oil separator 4, into the accumulator 20, where any
liquid refrigerant is collected so as not to slug the compressor 1.
The vapor refrigerant within the accumulator 20, which has absorbed
heat from the interior air passing through the system's first air
handler 17, is pulled into the compressor by means of the
compressor's suction intake. The refrigerant is compressed by the
compressor 1, and exits the compressor 1 by means of the
compressor's 1 hot gas refrigerant vapor discharge line 22, where
the entire process is repeated for as long as operation in the
dehumidification mode is called for. The wiring of a control box
23, containing a temperature control/thermostat 23A and a humidity
control/humidistat 23B, to operate the system in one of the cooling
mode and the dehumidification mode is well understood by those
skilled in the art and is not shown herein in detail. However, a
control connecting wire 24A is shown connecting the control box 23,
containing a thermostat 23A and a humidistat 23B, with the first
air handler's 17 fan 25; a connecting wire 24B is shown connecting
the control box 23 with the closed second solenoid valve 8; a
connecting wire 24C is shown connecting the control box 23 with the
second air handler's 6 fan 9; a connecting wire 24D is shown
connecting the control box 23 with the open first solenoid valve 5;
and a connecting wire 24E is shown connecting the control box 23
with the system's compressor 1.
[0052] FIG. 2 is a side view of ductwork 10, with the interior air
directional flow shown by arrows 3 within the ductwork 10, entering
both the first interior air handler 17 and the second interior air
handler 6 from a common air return 25 ductwork 10. The interior air
passes through both interior air handlers, 6 and 17, while the
system is operating in the dehumidification mode, and then
co-mingles as the interior air travels through the common air
supply 26 ductwork 10, thereby neutralizing the cooling effect of
the first air handler 17 prior to the interior air's distribution
into the interior air space by means of individual air supply ducts
(not shown herein as supply air ducts are well understood by those
skilled in the art).
[0053] FIG. 3 is a side view of a simple version of a deep well
direct expansion geothermal heat pump system, operating in a
dehumidification mode.
[0054] A refrigerant fluid (not shown) is transported, by means of
a compressor's 1 force and suction, throughout the system and
to/from various system components by means of refrigerant transport
tubing 2. The directional flow of the refrigerant fluid within the
refrigerant transport tubing 2 is shown by arrows 3 within the
tubing 2.
[0055] The refrigerant flows from the compressor 1 through an oil
separator 4, through an open first solenoid valve 5, and then
through the secondary interior air heat exchange means (secondary
air handler with finned tubing) 6, where most of the heat within
the refrigerant fluid is transferred back into the interior air
(not shown). In the cooling only mode of operation, and not in the
dehumidification mode, the first solenoid vale 5 would be closed
(not shown here as closed) and the refrigerant would flow through
the by-pass line 7 and around the secondary air handler with finned
tubing 6, and through the second solenoid valve 8, which is
alternately shown here in a closed position so as to reflect
dehumidification mode operation. In an alternative means of cooling
only mode of operation, the first and second solenoid valves, 5 and
8, and the by-pass refrigerant transport line 7 could be entirely
eliminated and the secondary air handler's 6 fan 9 could simply be
disengaged, with no electrical power supplied to operate it,
thereby preventing any material airflow through the ductwork 10
containing the secondary air handler 6.
[0056] The refrigerant next flows through the system's reversing
valve 11, and down into the sub-surface geothermal exterior heat
exchange means 12. Exiting the exterior heat exchange means 12,
which has absorbed the minor amount of heat generated by the
system's compressor 1 and fan 9, the refrigerant flows past a pin
restrictor expansion device 13, for use in the heating mode of
operation, through an open check valve 14, through a receiver 15,
and through a self-adjusting thermal expansion device 16. The
refrigerant then flows through the system's primary and first
interior air heat exchange means (first air handler) 17, where the
interior air is sensibly cooled and where latent load humidity is
removed. The condensed humidity is drained away by means of a
condensate drain line 18.
[0057] Lastly, the refrigerant flows from the primary and first air
handler 17, through the reversing valve 11, past the oil return
line from the oil separator 4, into the accumulator 20, where any
liquid refrigerant is collected so as not to slug the compressor 1.
The vapor refrigerant within the accumulator 20, which has absorbed
heat from the interior air passing through the system's first air
handler 17, is pulled into the compressor by means of the
compressor's suction intake. The refrigerant is compressed by the
compressor 1, and exits the compressor 1 by means of the
compressor's 1 hot gas refrigerant vapor discharge line 22, where
the entire process is repeated for as long as operation in the
dehumidification mode is called for. The wiring of a control box
23, containing a temperature control/thermostat 23A and a humidity
control/humidistat 23B, to operate the system in one of the cooling
mode and the dehumidification mode is well understood by those
skilled in the art and is not shown herein in detail. However, a
control connecting wire 24A is shown connecting the control box 23,
containing a thermostat 23A and a humidistat 23B, with the first
air handler's 17 fan 25; a control connecting wire 24B is shown
connecting the control box 23 with the closed second solenoid valve
8; a control connecting wire 24C is shown connecting the control
box 23 with the second air handler's 6 fan 9; a control connecting
wire 24D is shown connecting the control box 23 with the open first
solenoid valve 5; and a control connecting wire 24E is shown
connecting the control box 23 with the system's compressor 1.
[0058] In this example, the second air handler 17 is sized at 50%
of the first air handler 6 to enhance both heating and cooling mode
operation efficiencies, and a secondary by-pass refrigerant
transport line 29 is added around the first air handler 17 for use
in the heating mode of operation. The secondary by-pass line 29 is
operated by means of solenoid valves, 27 and 28. The solenoid valve
27, shown prior to the refrigerant flowing through the
self-adjusting thermal expansion device 16, is in the open position
so as to permit system operation in one of the cooling mode and the
dehumidification mode. The solenoid valve 28, shown after the
refrigerant has exited the first air handler 17, is in the closed
position so as to prevent system operation in the heating mode. A
control connecting wire 24F is shown connecting the control box 23
with the open third solenoid valve 5; and a control connecting wire
24G is shown connecting the control box 23 with the closed fourth
solenoid valve 28. As is well understood by those skilled in the
art, one reversing valve (not shown herein, but similar to the
system's reversing valve 11), or the like, can be substituted for
the two solenoid valves 27 and 28, and likewise, one reversing
valve (not shown herein, but similar to the system's reversing
valve 11) can be substituted for the two solenoid valves 5 and 8,
with the same effect of by-passing the desired air handler for
system operation in one of the cooling mode and heating mode, or of
not by-passing either air handler, 6 and 17, for operation in the
dehumidification mode.
[0059] Also, although not shown herein, the first air handler may
be one of completely and mostly by-passed, while the system is
operating in the heating mode, by various other alternative means
other than by means of solenoid valves and a by-pass refrigerant
transport line, as are well understood by those skilled in the art,
such as, for example, by disengaging the first air handler's fan
and thereby materially reducing the heat transfer over the first
air handler's finned tubing.
[0060] Should one simply eliminate the solenoid valves 5,8,27, and
28, and eliminate the by-pass lines 7 and 29, and eliminate the
reversing vale 11: one may selectively operate the system in the
cooling mode by simply activating the fan 25 in the first air
handler 17, and by deactivating/disengaging the fan 9 in the second
air handler 6; one may selectively the system in the heating mode
by simply deactivating/disengaging the fan 25 in the first air
handler 17, and by activating the fan 9 in the second air handler
6; and one may selectively the system in the heating mode by simply
activating the fan 25 in the first air handler 17, and by
activating the fan 9 in the second air handler 6; all by means of
the thermostat 23A and humidistat 23B control box 23, which can
also control the desired CFM airflow in each of at least one
desired operative air handler, 17 and 6.
* * * * *