US 20140231042A1
(19) United States
(12) Patent Application Publication (10) Pub. No.: US 2014/0231042 A1
Curry et al.
(54)
(43) Pub. Date:
SYSTEM FOR REDUCING THE
Aug. 21, 2014
Publication Classi?cation
CONDENSING TEMPERATURE OF A
REFRIGERATION OR AIR CONDITIONING
SYSTEM BY UTILIZING HARVESTED
RAINWATER
(51)
[1113- C1
F28C 3/08
US. Cl.
(52)
(2006.01)
CPC ...................................... .. F28C 3/08 (2013.01)
(71)
ApplicantSIThOInaS R- Curry, Fishers, IN (US);
USPC ......................... .. 165/47; 165/104.19; 165/96
Adam M. Curry, Chicago, IL (US)
57
(72) Inventors: Thomas R. Curry, Fishers, IN (U S);
Adam M- curry, Chicago; IL (Us)
An evaporative air conditioning heat transfer apparatus com
prising a collection surface for diverting liquid into a channel,
a reservoir capable of receiving and storing the diverted liq
(21) Appl' N05 14/052,823
,
(22)
ABSTRACT
( )
_
uid, at least one conduit for transferring liquid from the res
Flled'
oct' 14’ 2013
ervoir to a liquid dispersion point, and a regulator positioned
.
.
between the reservoir and the liquid dispersion point and
Related U'S'Apphcatlon Data
con?gured to control the amount of liquid released at the
(60) Provisional application No. 61/766,242, ?led on Feb.
liquid dispersion point, Wherein the liquid dispersion point is
19, 2013.
con?gured to distribute the liquid over a condensing coil.
102
120
100
114
104
5
f
x
/
/'
V
m
-—
110
v
g
,
,
122
1
l1
112
1
j
2
I;
llll
l
m
g
I
/
,
108 \—d
,4
118
/
106
L_._-._.__.._-..._.J
F!
L]
f
j
?)
/
.4
’
/
,
Patent Application Publication
Aug. 21, 2014 Sheet 1 0f 7
US 2014/0231042 A1
I1ZJTD
110
U
118 H
I
122
100
k112X Q
H
108\
/L
106
Patent Application Publication
Aug. 21, 2014 Sheet 2 0f 7
US 2014/0231042 A1
120
102
204
208
L\\\\\\\\\\\\\\\\\\ \\\L\L
as
114
110
112
200
108
106
206—")
2Figure
Patent Application Publication
Aug. 21, 2014 Sheet 3 0f 7
US 2014/0231042 A1
)2
304
B 5
114
3Figure
120
U. 11‘'1
300
J1
106
Patent Application Publication
Aug. 21, 2014 Sheet 4 0f 7
US 2014/0231042 A1
m@“6 0 m3mow“ M0HU5B/0x
new
mL.i1‘i4<cuwsonv
0m.5th
$5 £023 %—
@28ng wico U
:mD
“0329
Patent Application Publication
Aug. 21, 2014 Sheet 5 0f 7
US 2014/0231042 A1
404
5
g
i
.
"a
[—q \
3:2}; 3: \\\\\\\\\Y\\\ \
E
K. v
Q)
L4
a
N
5
E»
a
E
II
#21 I
O
s;
2_/ 5:3-E
106
g
Patent Application Publication
Aug. 21, 2014 Sheet 6 0f 7
US 2014/0231042 A1
mQ“Eda m?mow“
E8:<60D w cDow O :wcioOwcoU
H
303
&
HcomuwmcoU
2if3on 235
@me
8i68 QwimEcoDw U
cow
HemwBQEoU
wgswm
£6soc sw
Patent Application Publication
Aug. 21, 2014 Sheet 7 0f 7
US 2014/0231042 A1
MA:PHEQ
@2068>?
4<::00$656.50
o:ug<?w
l"
£62a83wq“uA:
OW:wim2co3n U
mm“52: m3wmdw
b
cow:<30
36590
SE
HewmonEU
cousm
h95me
Aug. 21,2014
US 2014/0231042 A1
SYSTEM FOR REDUCING THE
CONDENSING TEMPERATURE OF A
REFRIGERATION OR AIR CONDITIONING
SYSTEM BY UTILIZING HARVESTED
RAINWATER
CROSS-REFERENCE TO RELATED
APPLICATIONS
[0001] This application is related and claims priority to
US. Provisional Patent Application Ser. No. 61,766,242 ?led
on Feb. 19, 2013, the complete and entire disclosure of which
is hereby expressly incorporated by reference herein.
TECHNICAL FIELD
[0002] The present disclosure relates to refrigeration and
air conditioning systems and speci?cally to processes and
methods for reducing the condensing temperatures of such
systems by sprinkling harvested rainwater over standard (or
manufacturer’s modi?ed) condensing coils to thereby allow
evaporative condensing to take place.
BACKGROUND OF THE INVENTION
[0003]
Most air conditioning and refrigeration systems uti
lize the Carnot Cycle, which is a vapor-compression refrig
eration type of system. The basic components of this Carnot
Cycle system consist of a compressor, a condenser, an expan
sion valve, and an evaporator. The majority of the energy
that the refrigerant gas will “give up” its latent heat to be
condensed from a gas (at condenser pressure) to a liquid (at
condenser pressure). The driving force for condenser heat
transfer is 95° F. air (a typical design summer day in many
parts of the United States) being drawn across a condenser
coil with a refrigerant temperature at 115° F. to 130° F. This
driving force or temperature differential is 20 or 35 Fahren
heit degrees.
[0008] An air conditioning unit with an air-cooled con
denser can have a typical energy input of 1.3 KW per ton at
peak load on a design summer day. Large commercial and
industrial air conditioning and refrigeration systems typically
utilize water-cooled or evaporatively cooled equipment
which have cooling towers or evaporative condensers for
achieving low condensing temperatures, particularly since
cooling towers and evaporative condensers reject their heat
based on ambient wet bulb temperatures (78° F. is a typical
design wet bulb temperature for many places in the United
States), as opposed to air-cooled equipment that reject heat
against 95° F. typical summer dry bulb temperatures. Since
cooling tower and evaporative condenser systems can get
condensing temperatures to “approach” wet bulb temperature
by 15 to 20 Fahrenheit degrees, a KW per ton energy usage of
0.6 to 0.9 KW per ton can be realized. Water cooled and
evaporative cooled equipment can consume nearly half of the
energy per ton as air cooled equipment. Although larger sys
tems utilize water cooled and evaporative cooled equipment
for the sake of energy savings, these types of systems have a
input (typically electricity) is supplied to the compressor. The
higher ?rst cost, a higher maintenance cost, and usually
energy required to operate the compressor is largely a func
tion of the “lift” or the compression ratio against which the
compressor has to operate. The type of refrigerant also has
require more maintenance time due to water treatment con
some effect upon the amount of energy that is required to
produce one ton of refrigeration (air conditioning), but the
selection of refrigerant is typically based upon the environ
mental suitability of the speci?c refrigerant, as well as the
cost of the refrigerant.
[0004] The compressor “lift” can be best described as the
pressure (condensing pressure) to which a compressor must
cerns, etc. If properly maintained, water cooled and evapora
tively cooled equipment and systems will have a longer oper
ating life.
[0009]
To achieve a maximum ef?ciency in air condition
ing and refrigeration systems, various means of lowering
condensing pressures and corresponding saturated tempera
tures have been employed to achieve a low kilowatt input per
ton of refrigerating effect. These methods vary according to
ambient temperatures (both wet bulb and dry bulb), ?rst co st
considerations, simplicity and ease of operation and mainte
elevate the incoming pressure (suction pressure). A Mollier
Diagram for the speci?c refrigerant can precisely illustrate
the thermodynamics of the compression portion of the Carnot
nance.
Cycle.
conditioning and refrigeration systems use air as a medium to
[0005]
The compression ratio is often used by the compres
sor designer to describe the capability of a compressor geared
towards a speci?c applicationii.e., the compression ratio is
the ratio of the absolute pressure at the condensing tempera
[0010]
Virtually all residential and small commercial air
remove heat from the condensing side of the refrigeration
cycle. These systems are normally rated with 95° F. ambient
air on the condenser. Mo st air conditioning and refrigeration
systems will condense the standard refrigerants from a high
ture (pressure) to the absolute pressure at the saturated suc
pressure gas to a liquid at 115° F. to 130° F. depending upon
tion temperature (pressure). The greater the compression
the ef?ciency of the system and speci?cally, the thermal heat
rejection size of the condenser. These air cooled condensers
ratio, the more energy that is required to raise the refrigerant
gas from the suction pressure to the condensing pressure (i.e.,
the compression cycle).
primarily are constructed of copper tubes and aluminum ?ns
(spaced at 12 to 16 ?ns per inch) or a “spiny” type of extended
Typically, a standard air conditioning system oper
surface. The copper tubes, through which the refrigerant
ates at an evaporator temperature (saturated suction tempera
ture and pressure) of +40° F. or +50° F. In the industry, it is
commonly denoted as 40 F or 50 F. The corresponding satu
?ows, are typically one to four rows that are in a staggered
[0006]
rated pressure varies according to the particular refrigerant
being used. On the other hand, the compressor discharge
pressure (condensing pressure less line losses) is a function of
the method of condensing that is used.
[0007] Residential and small commercial air conditioning
and refrigeration systems utilize “air-cooled” condensing.
con?guration. The ?nned tubes make this an extended surface
heat exchanger with the refrigerant gas being condensed
within the tubes at 115° F. to 130° F. with cool air at 95° F.
being drawn across the ?nned condenser coil by means of a
fan.
[0011]
The refrigerant gas in the condenser is condensed
from a high pressure gas at the condensing temperature to a
high pres sure liquid at the same temperatureimerely a phase
This means that ambient air must be suf?ciently lower in
change. This high pressure liquid then ?ows to an expansion
temperature than the refrigerant condensing temperature so
device (capillary tube, expansion valve, etc.) that expands the
Aug. 21,2014
US 2014/0231042 A1
refrigerant from a high pressure liquid to a gas. This expan
sion of the refrigerant from a high pressure liquid to a low
pressure gas occurs in the evaporator coil in the refrigeration
system which results in the “cooling effect” or the “refriger
ating effect.” The typical evaporator coil temperature in a
residential air conditioning system may be 40° F. to 50° F,
with the lower coil temperature providing for dehumidi?ca
tion by condensing moisture out of the air. This evaporator
coil provides both sensible and latent heat transfer.
[0012] The expansion device tries to regulate the coil tem
signed and installed systems. There are many reasons why
once-through water systems have fallen out of favor. The
main reason stems from the formation of the Environmental
Protection Agency (EPA) and the many and varied aspects of
the Clean Water Rules and Regulations that have been
enacted since the 1970’s. These regulations regarding the
water quality mandates for city and municipal water systems
have raised the cost of water to be $1.00 to $4.00 per 1,000
gallons of water usage. More importantly, the cost of disposal
of this once-through water can be two or three or four times
perature so as to maintain at least 10 Fahrenheit degrees of
the cost of purchasing the water. The cost of the various types
“super heat” which insures that all refrigerant that exits the
evaporator coil is a gas. Refrigeration compressors only want
to see gasino liquids. The gas leaving the evaporator coil is
and effectiveness of municipal sewage treatment plants has
driven sewage disposal costs up. In short, today, in the United
States, merely discharging water into ditches, streams, etc. is
saturated with some amount of “super heat.” This suction gas
is then drawn into the compressor which then raises this 40°
F. to 50° F. refrigerant gas at its saturated pressure to the
condensing pressure at the corresponding 115° F. to 130° F.
not permitted by the EPA. Essentially, the only legal way of
discharging once-through water is through the municipal
sewage treatment plants. The cost of purchasing once-though
water and disposing it through the municipal sewage treat
pressure. A halocarbon refrigerant that has been commonly
used in air conditioning and refrigeration systems is R-22,
ment plant can be cost prohibitive.
[0017] The other often over-looked but major detriment to
once-through water systems relates to the water quality itself
Well water contains many dissolved minerals such as iron and
calcium carbonate. These dissolved minerals will foul con
chlorodi?uoromethane. As an example, the corresponding
saturation pressure at 40° F. evaporator temperature is 83
PSIA. The corresponding pressure at 115° F. condensing
temperature is 257 PSIA. The compressor work (energy)
required to raise a refrigerant gas from 83 PSIA to 257 PSIA
densers causing the condensers to gradually lose their heat
transfer effectiveness resulting in a major loss of system
requires typically 1.2 to 1.4 kilowatts per ton of refrigerating
effect.
ef?ciency and ultimately leading to condenser failure.
[0013] Many larger air conditioning and refrigeration sys
tems are known as “water-cooled” systems. Many of these
systems will condense refrigerant in the condenser at 95° F. to
105° F. The corresponding R-22 pressures are 196 and 225
PSIA, respectively. Since the compressor does not have to
raise the refrigerant from the evaporator pressure to as high of
condensing pressure in a water cooled system, the compres
sor energy requirement is much less. Many “water-cooled”
systems can operate at 0.60 to 0.90 KW/ton, or lower.
Although the energy usage per ton on a water-cooled system
is signi?cantly less than an air-cooled system, the ?rst cost of
water-cooled systems is signi?cantly more thus relegating
water-cooled systems to large commercial and industrial
applications.
[0014] Water-cooled systems typically fall into three gen
eral categories of heat rejection apparatus and system con
?guration. They are: a) once-through water systems; b) cool
ing tower water systems; and c) evaporative condenser
[0018] The most common means of condensing refrigerant
gas from a high pressure gas to a high pressure liquid include
the following: Water-Cooled Condensers; Air-Cooled Con
densers; Evaporative Cooled Condensers; Adiabatic Air
Cooled Condensers.
[0019] Water-cooled condensers are most commonly used
on large commercial and industrial air conditioning systems
that demand an optimum of energy ef?ciency. Most water
cooled systems utilize an evaporative cooling tower where
some water is evaporated to cool the balance of the water.
Since heat is rejected by evaporation, the water can be cooled
to a temperature that “approaches” the wet bulb temperature.
The wet bulb temperature is always equal to or lower than the
dry bulb temperature. Hence, the lower wet bulb temperature
can directly relate to a lower condensing temperature in the
water-cooled air conditioning apparatus resulting in a lower
energy input requirement for a ton of refrigerating effect.
[0020]
The three most commonly thought of thermody
ing temperature. Generally speaking, the water temperatures
namic properties of air are dry bulb temperature, wet bulb
temperature, and relative humidity which are all interrelated.
Cooling towers are rated only on wet bulb temperature. Of
these three, the wet bulb temperature is the least understood.
The psychrometrics of air de?ne wet bulb as the temperature
at which water evaporates. Although the dry bulb temperature
of once-through cooling water are not affected by ambient air
temperatures or the thermodynamics of air. Once-through
wet bulb temperatures do not exceed 86° F. The normal peak
systems. To understand water-cooled systems, an understand
ing of the thermodynamics of air is necessary.
[0015] A once-through water-cooled system removes heat
in the condenser by sensible heat transfer, taking advantage of
the cool well water or city water to achieve the low condens
systems consist of water-cooled shell and tube or plate con
densers that have refrigerant gas on one side of the heat
exchanger and city or well water on the other side. This water
can rise to over 120° F. at places on earth, the highest ambient
design ambient temperature in many parts of the United
States is 95° F. dry bulb temperature and 78° F. wet bulb
temperature.
source (city or well) can typically be 60° E. which easily
permits refrigerant condensing to occur at 80° F. or 90° F. The
water enters the condenser at, say, 60° F. and is discharged to
This differential of 7 Fahrenheit degrees (85° F.-78° F.) is
the sewer at 80° F. to 90° F. The water usage could amount to
known as the “approach temperature.” This differential is the
1 to 2 gallons per minute of water per ton of refrigerating
effect.
“driving force” that allows for evaporation to take placeithe
key method of heat transfer in evaporative cooled systems.
[0016]
This latent heat transfer takes advantage of the fact that every
pound of water that evaporates, releases 1,000 BTU’ s of heat
Once-through water systems have not been popular
for many years although are still used on many older-de
[0021] Most cooling towers have a standard rating of pro
ducing 85° F. cold water when the ambient wet bulb is 78° F.
Aug. 21,2014
US 2014/0231042 A1
into the atmosphere (a reasonably close approximation of the
latent heat of vaporization of water).
[0022] A cooling tower is an evaporative heat exchanger
where water to be cooled is distributed over an evaporating
surface while air is forced through or drawn over this surface
perature that very closely approaches the ambient wet bulb
temperature. This saturated air temperature entering an air
cooled condenser is 10 to 15 Fahrenheit degrees lower than
typical dry bulb temperature that a standard air-cooled con
denser would see.
to enhance evaporation.
[0023] On the typical hottest day of the summer (95° F. dry
bulb temperature and 78° F. wet bulb temperature) a cooling
[0030] Most attempts to increase air conditioning and
refrigeration system ef?ciency have been devoted to larger
systems which typically have operating staffs and budgets
tower can produce 85° F. cold water evaporatively. This 85° F.
water is pumped into the condenser of a water-cooled air
conditioning or refrigeration unit. This cold water (that enters
the condenser at 85° F. and would typically leave at 95° F.)
extracts heat in this water-cooled condenser by sensible heat
transfer.
that permit the use of water-cooled systems with cooling
towers or evaporative condensers. These larger systems also
have the ability and infrastructure to accommodate the use of
water for evaporation, the water treatment hardware and
chemicals required to treat the water to minimize scaling and
[0024] Again, by taking advantage of evaporative heat
a necessary part of any water treatment system.
transfer, water-cooled systems allow the condensing tem
perature of the refrigeration cycle to be 95° F. to 105° F.
water or well water directly on an air conditioning ?nned
biological activity, and the disposal of bleed-off water that is
[0031]
Some isolated cases include the spraying of city
versus the higher condensing temperatures of 1 15° F. to 130°
F. in air-cooled condensers.
[0025] There are advantages and disadvantages to water
condenser coil to reduce the condensing temperature. The
mineral build-up on the ?nned condenser from the spraying of
cooled systems utilizing cooling towers. The fundamental
viceable. This coil spraying most closely approximates an
city or well water very quickly renders the condenser unser
reason that a cooling tower is used is that it saves the user
evaporative condenser although evaporative condensers do
nearly 95% of the water that might be used in a once-through
not have ?nned coils and normally do have a good water
treatment system and program.
[0032] Since directly spraying a ?nned air cooled con
denser coil creates problems with coil scaling, etc. due to the
dissolved minerals normally found in all water sources, vari
ous attempts have been made to saturate air adiabatically via
system. However, many owners and users don’t want to have
to address the water treatment systems and chemicals that are
inherently a part of a cooling tower system. Aside from scale
and corrosion control that can be accomplished by chemicals
and chemical treatment or electronically/magnetically in
non-chemical treatment systems, biological control is also
pads or some other method. These adiabatic units are found in
required.
small commercial units (approximately 50 to 100 tons) and
[0026] It must be recognized that a recirculating type of
cooling water system of which a cooling tower is an integral
have been discussed in Us. Patent Publication No. US2010/
0242534 A1 and Us. Pat. No. 5,701,748. At this point, for a
variety of reasons, these adiabatic systems have not proven to
part tends to concentrate the dissolved minerals that are in the
water. These dissolved minerals can scale or foul the heat
transfer surfaces. This is why water treatment is required.
[0027]
Air-cooled condensers are most commonly used on
residential and small commercial air conditioning and refrig
erating systems due to simplicity of operation and low ?rst
be viable options for lowering the condensing temperature on
residential and small commercial air conditioning and refrig
eration systems.
[0033] The present invention is intended to improve upon
and resolve some of these known de?ciencies of the art.
cost. Since heat is transferred from the refrigerant gas at the
refrigerant’s condensing temperature (and corresponding
SUMMARY OF THE INVENTION
pressure), the system’s condensing temperature can only
practically “approach” the ambient air dry bulb temperature
[0034] In accordance with one aspect of the present disclo
sure, an evaporative air conditioning heat transfer apparatus is
provided and comprises a collection surface for diverting
liquid into a channel, a reservoir capable of receiving and
storing the diverted liquid, at least one conduit for transferring
liquid from the reservoir to a liquid dispersion point, and a
regulator positioned between or inside of the reservoir and the
by 20 to 35 Fahrenheit degrees. This high condensing tem
perature and resultant higher energy input per ton of refrig
erating effect is the penalty that owners and users pay to
achieve simplicity and a low ?rst cost.
[0028] Evaporative condensers are most commonly used
on large air conditioning and refrigeration systems due to the
requirement of optimal energy input per ton of refrigerating
effect. Here the refrigerant gas transfers its heat at the sys
tem’ s condensing temperature which approaches the ambient
wet bulb temperature. Practically, most evaporative condens
ers generate a condensing temperature that approaches the
ambient wet bulb temperature by 12 to 17 Fahrenheit degrees.
Although evaporative condensers can generate condensing
temperatures that approach wet bulb temperatures by 5 to 10
Fahrenheit degrees, the ?rst cost of the evaporative condens
ers and the physical space required by these over-sized units
liquid dispersion point, the regulator being con?gured to con
trol the amount of liquid released at the liquid dispersion
point. In accordance with this aspect of the present disclosure,
the liquid dispersion point is con?gured to distribute the
liquid over a condensing coil.
[0035]
In accordance with certain embodiments, the regu
lator can be a valve or a pump, while the collection surface can
be a roof of a house, building, or some other structure, (having
a series of channels or gutters for diverting the liquid to the
reservoir) or trench or some other means of capturing and
conveying water to the reservoir from ground gutters, ground
are detriments.
pipes, or other property rainwater drainage systems as may be
[0029]
present.
Adiabatic air-cooled condensers are seldom used
pared with air-cooled condensing systems.Adiabatic systems
[0036] To transfer the liquid from the reservoir to the liquid
dispersion point, any series of conduits or pipes can be uti
lized in accordance with certain embodiments. Moreover, in
are characterized by adiabatically saturating the air to a tem
accordance with certain aspects herein, the liquid dispersion
due to the complexity of the apparatus and system (installa
tion, operation, maintenance, and higher ?rst cost) as com
Aug. 21,2014
US 2014/0231042 A1
points that are con?gured to release the liquid transferred
from the reservoir can be one or more sprinkler heads or
gravity distribution pipes or troughs that are positioned proxi
mate the condensing coil (or coils) of an air conditioning
system.
[0037] To release the liquid from the liquid dispersion
[0044] Other objects and bene?ts of the invention will
become apparent from the following written description
along with the accompanying ?gures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0045]
The above-mentioned aspects of the present inven
points, in accordance with certain aspects of the present dis
tion and the manner of obtaining them will become more
closure, a regulator, such as a valve or pump, can be used to
apparent and the invention itself will be better understood by
reference to the following description of the embodiments of
the invention taken in conjunction with the accompanying
control the amount of liquid released over the condensing
coils. Further, a controller can be incorporated into the system
to mechanically or electronically drive the regulator if
desired.
[0038] In accordance with still another aspect of the present
disclosure, a method for cooling refrigeration condensing
coils is provided. According to this embodiment, rainwater is
drawings, wherein:
[0046]
FIG. 1 is a ?ow diagram of an illustrative evapora
tive air conditioning heat transfer system in accordance with
the teachings of the present disclosure and having an outdoor
tank above ground;
collected in a reservoir that is ?uidly coupled to one or more
[0047]
dispersion units, such as sprinkler heads or gravity distribu
tion pipes or troughs. The rainwater is capable of being dis
tive air conditioning heat transfer system in accordance with
the teachings of the present disclosure and having an outdoor
tributed from the one or more dispersion units onto a con
densing coil of an air conditioning unit, while the amount of
tank in ground with a pump;
[0048] FIG. 3 is a ?ow diagram of an illustrative evapora
rainwater distributed onto the coil can be regulated by a valve
or pump that is located between the reservoir and the liquid
tive air conditioning heat transfer system in accordance with
the teachings of the present disclosure and having an indoor
dispersion points.
[0039]
In accordance with certain aspects of the present
disclosure, the reservoir can be positioned above the one or
FIG. 2 is a ?ow diagram of an illustrative evapora
tank above ?oor with a pump;
[0049] FIG. 4 is a ?ow diagram of an illustrative evapora
more dispersion units to permit gravity to provide suf?cient
tive air conditioning heat transfer system in accordance with
the teachings of the present disclosure and having an indoor
water pressure for distributing the rainwater onto the con
densing coil from the one or more dispersion units. Altema
tank in ?oor with a pump;
tively, in accordance with yet other embodiments, the reser
conventional evaporatively modi?ed air-cooled condensing
voir can be positioned below the one or more dispersion units
and a pump used to provide suf?cient water ?ow and pressure
present disclosure;
for distributing the rainwater onto the condensing coil from
the one or more dispersion units.
[0040] In accordance with some embodiments, the rainwa
ter dispersed onto the condensing coil can be collected and
returned to the reservoir.
[0041] In accordance with still other embodiments, the pro
cess of regulating the amount of rainwater that is distributed
by the one or more dispersion units onto the condensing coil
can further include interpreting one or more sensors associ
ated with the system to thereby determine when to distribute
the rainwater onto the condensing coil (e. g., to determine
whether or not the correct conditions are present for opening
or closing the valve and/or for supplying electricity to the
pump) and what quantity of rainwater is required to achieve
the desired condensing temperature.
[0042] This particular embodiment may include an appa
ratus for minimizing the effects of suspended solids in the
[0050]
FIG. 5 is a heat balance ?ow diagram illustrating a
unit that can be used in accordance with the teachings of the
[0051]
FIG. 6 is a heat balance ?ow diagram illustrating a
conventional air-cooled condensing unit; and
[0052]
FIG. 7 is a heat balance ?ow diagram illustrating a
conventional adiabatic air-cooled condensing unit; and
DETAILED DESCRIPTION
[0053]
The embodiments of the present invention
described below are not intended to be exhaustive or to limit
the invention to the precise forms disclosed in the following
detailed description. Rather, the embodiments are chosen and
described so that others skilled in the art may appreciate and
understand the principles and practices of the present inven
tion.
[0054]
Unless de?ned otherwise, all technical and scien
ti?c terms used herein have the same meaning as commonly
understood by one of ordinary skill in the art to which this
invention belongs. Although any method and materials simi
rainwater such as a gutter leaf guard. Further, to minimize the
lar or equivalent to those described herein can be used in the
effects of suspended solids in the rainwater, this embodiment
practice or testing of the present invention, illustrative meth
may have ?ltration devices such as a barrier ?lter, a screen, a
ods and materials are now described.
cartridge, a centrifugal separator, or a settling ?lter.
[0043] In a different embodiment, a system for cooling
to systems and methods for retro?tting existing air-cooled
[0055] Generally speaking, the present application relates
refrigeration condensing coils is described. This particular
condensers and condensing units (or new condensers or con
system may have a reservoir for receiving and storing rain
water. The reservoir may be connected to liquid dispersion
densing units as would be designed by air conditioning unit
points by a conduit or series of conduits. Further, a controller
can be electrically coupled to a controller and con?gured to
manufacturers) to spray, sprinkle or otherwise distribute
water over condensing coils (?nned tube or other designs of
distribute speci?c amounts of liquid to a liquid dispersion
air-cooled condenser coils) to lower condensing tempera
tures, thereby reducing power consumption. In accordance
point. In this embodiment, the regulator could be a valve or a
pump. Finally, the controller can have a plurality of sensors
water can be used as an evaporation source, particularly as
that are interpreted by the controller to determine appropriate
amounts of liquid to distribute to the dispersion point.
and clog condenser coils.
with certain aspects of the present disclosure, harvested rain
such water is free from dissolved minerals that typically foul
Aug. 21,2014
US 2014/0231042 A1
[0056] In terms of the means that may be used to spray
water on an air-cooled condenser coil in accordance with the
or a valve. The logic board on the controller can analyze the
inputs and determine whether certain conditions are justi?ed
present disclosure, it should be understood and appreciated
to manipulate the regulator to supply varying amounts of
herein that there are various different known processes that
can be used to wet the coil. While some of these conventional
water.
processes seek to minimize fouling of the coil with dissolved
minerals while maximizing coil wetting, the present inven
tors have found a way to address these efforts by using min
eral-free rainwater to wet a ?nned condenser coil. In fact, as
many existing processes for spraying water on condenser
coils have been unfavorably received due to excessive water
usage (expensive) and condenser fouling in response to dis
solved minerals that have precipitated out of the water, the
presently disclosed methods are particularly useful for elimi
[0062] The ESRACHTS system provides the energy ef?
ciency that approximates that of water cooled and evapora
tively cooled systems on standard residential and small com
mercial systems while not having to deal with the many
maintenance and operational issues that are normally found
in large water cooled and evaporatively cooled systems.
[0063]
One non-limiting advantage of the ESRACHTS
System is that residentially (and on small commercial sys
tems), lower condensing temperatures (and the inherent
energy ef?ciency) are not commercially available at reason
nating and overcoming these problems traditionally experi
enced by existing technologies.
able costs to homeowners or a small commercial businesses.
[0057] An Evaporative/ Sensible Refrigeration/Air Condi
tioning Heat Transfer System (see FIGS. 1, 2, 3 and 4, for
instance) (hereinafter known as ESRACHTS) utilizes rain
of water to gain a lower condensing temperatureia concept
that is currently only available to large commercial and indus
This ESRACHTS System takes advantage of the evaporation
water (distilled water) to directly wet a standard, commer
trial users who can devote the maintenance and service people
and other resources necessary to own and operate large air
cially designed and manufactured air-cooled, ?nned coil con
denser which is integral to a condensing unit (a package unit
do not have those resources. In short, air-cooled air condi
that includes a compressor, perhaps a suction accumulator,
tioning and refrigeration systems tend to be simpler, less
condensing coil, condenser fan, and electrical safety and
operating controls) that is typically the “outdoors” portion of
a “split system” residential (and also small commercial) air
conditioning system. Many of these “split systems” are also
costly, and easier to operate than water cooled systems.
designed and operated as reverse cycle heat pumps (air
source). The reduction of the condensing temperature of an
air conditioning or refrigeration system results in energy sav
tial and small commercial system is a bene?cial aspect of this
ings.
conditioning and refrigeration plants. Residential customers
Energy ef?ciency is normally sacri?ced so as to achieve a low
?rst cost and an ease of operation and maintenance.
[0064]
Harvesting of rainwater for evaporation on residen
present disclosure, particularly as it allows existing air con
ditioning and refrigeration equipment to undergo minimal
and reasonable on-site modi?cations to implement an
[0058] Before going into speci?c details regarding the pres
ently disclosed system, it should be appreciated herein that
ESRACHTS System.
reduce energy usage and reduce peak electrical demand. The
rainwater harvesting allows for the water that is distributed
over the condensing surfaces to be mineral-free thus keeping
the heat transfer surfaces clean.
[0059] The various designs of condensers in an air-condi
tioning or refrigeration system can include of some of the
[0065] Most water-cooled systems are of a recirculating
type that require extensive scale and corrosion control water
treatment procedures (chemical or non-chemical) in order to
insure that the air conditioning equipment does not “scale
up” or corrode, causing it to lose ef?ciency and become
unserviceable. The city water or well-water that is typically
used for make-up water on large water-cooled systems are
laden with many dissolved minerals, with Calcium Carbonate
(CaCO3) being the most common and most troublesome.
[0066] By way of example, a water-cooled system that is
100 tons in size (somewhat small for water-cooled systems)
following: extended- surface ?nned tube condensers; partially
?nned, partially bare tube prime surface condensers; all prime
surface bare tube condensers; and plate condensers.
operates on an air conditioning system for 2,000 hours a year
at a 40% load factor. The system consists of an evaporative
cooling tower that cools condenser water serving a 100-ton
[0060]
water cooled chiller or 100 tons of self-contained water
the ability to harvest rain (known as rainwater harvesting) and
store it for use during times of air conditioning or refrigera
tion system operation, has signi?cant application in residen
tial, commercial, and industrial installations as a means to
The system for distributing water over the con
denser coil can be a gravity water system or a low pressure
cooled air conditioning units. Assuming that a water-cooled
nozzle spray type system. Moreover, the water source can be
a rainwater harvesting tank positioned such that water can
system operates at 1.30 KW per ton, the Energy Analysis of
?ow by gravity to a distribution system that will deliver the
water over the condenser coil. Likewise, water can be pumped
from a rainwater harvesting tank, reservoir or pit to a water
distribution system located at the condenser.
system operates at 0.75 KW per ton and that an air-cooled
each system (0.75 KW per ton, water-cooled ton versus 1.30
KW per ton, air cooled) on a design summer day where the
ambient dry bulb temperature is 95° F. and the coincident wet
bulb temperature is 78° F. (these are considered to be design
A simple control scheme that monitors condensing
summer days for many locales throughout the United States,
temperature and outdoor ambient air temperature can vary the
water usage to achieve a desired condensing temperature
while optimizing water usage. The control scheme can
include a controller with a plurality of inputs, a logic board,
and a plurality of outputs. The inputs into the control can
include sensors that detect various temperatures throughout
the system such as the condensing temperature and outdoor
ambient temperature. Further, the controller can have outputs
that can operate a regulator which could include either a pump
as published by the American Society of Heating, Refriger
ating, and Air Conditioning Engineers (ASHRAE)) can be
[0061]
determined as follows:
[0067]
AlR-COOLED 100 tons 1.3 KW/TR 2,000 annual
operating hours, 40% load factor: 100><1.3><2,000><0.40:104,
000 KWH annually. 104,000 KWH annual electrical usage at
a rate (which includes both energy charge and demand
charge) of $0.10 per KWH, the annual electric cost would be
$10,400.
Aug. 21,2014
US 2014/0231042 A1
[0068]
WATER-COOLED 100 tons 0.75 KW/TR 2,000
annual operating hours, 40% load factor: 100><O.75><2,000><
0.40:60,000 KWH annually. 60,000 KWH annual electrical
usage at a rate (which includes both energy charge and
of scale would accumulate annually. This amount of scale can
still create a loss of ef?ciency and create maintenance and
operating problems.
[0076] All methods of trying to reduce the scaling tendency
of water (water treatment, soft water, etc.) can be both costly
demand charge) of $0.10 per KWH, the annual electric cost
would be $6,000.
[0069] A Water Quality Analysis is as follows: A water
cooled system takes advantage of the latent heat of water
(approximately 1,000 BTU of heat removed per pound of
water evaporated). Therefore, taking into account the heat of
evaporatively cooled systems using well water or city water is
just not a viable option for residential and small commercial
compression, a 100-ton chiller or self-contained water-cooled
utilizes rainwater to wet an air-cooled ?nned or partially
and maintenance intensive. In addition, water cooled or
systems.
[0077]
Referring now to FIG. 1, an ESRACHTS system
air conditioning units will need to typically reject 15,000
?nned condensing surface so as to reduce the condensing
BTU/HR per ton of air conditioning.
[0070] The amount of water that is evaporated by a cooling
temperature of an air conditioning or refrigeration system
resulting in energy savings. In accordance with a ?rst illus
trative ESRACHTS system 100, rainwater can be harvested
tower for a 100 ton unit is as follows: 100 ton><15,000 BTU/
H-ton><1 lb. water/1,000 BTU:1,500 lbs. of water/hr.
[0071] The quality of city and well water varies widely all
from a collection surface such as a roof 102 or from a ground
level property drainage system and then collected in a storage
over the United States and worldwide. This water quality,
which is documented, can be as low as 50 to 75 parts per
million (ppm) of calcium hardness and as high as 500 or 600
ppm. Any hardness greater than 200 ppm is considered to be
“hard water,” while any water with less than 50 ppm of cal
cium hardness is considered to be “soft water.”
tank or reservoir 104 so as to provide mineral-free water to be
[0072]
108 without experiencing the precipitation of dissolved min
erals that would result in the fouling of the ?nned condensing
surfaces. Although harvested rainwater is absent of dissolved
minerals, some suspended (non-dissolved) solids may need to
be ?ltered from the rainwater, depending upon the con?gu
ration of the harvesting system. It should be understood and
appreciated herein that the method and degree of ?ltration
For the sake of this example, and assuming a cal
cium hardness of 150 ppm, as well as ignoring water treat
ment techniques that are required for minimizing scale depos
its and corrosion control that are mandatory with
recirculating cooling tower systems, a 100 ton cooling tower
will evaporate at peak load 1,500 pounds of water per hour.
The dissolved mineral potential that will precipitate out of
that water is calculated as follows: 1,500 lb./hr.><150 lbs. of
CaCO3/ 1,000,000 lbs. of wateF0.225 lbs. of CaCO3 (scale).
This is 0.225 lbs. of scale build up in one hour’s time. If, on a
design air conditioning day, the load was an average of 60
tons for 10 hours, the potential accumulation of scale would
be calculated as follows: 60 ton><15,000 BTU/hr.-ton><1 lb.
water/1,000 BTU><10 hour><150 lbs. ofscale/1 ,000,000 lbs. of
water. Total solids accumulation in one ten-hour day:1.35
lbs. of scale. This accumulation would be on the heat transfer
surfaces (inside the tubes of a water-cooled condenser or the
outside of the tubes of an evaporative condenser/cooler).
[0073] Over an entire air conditioning season (100 tons,
2,000 annual operating hours, 40% load factor), the accumu
lation of scale could amount to as follows: 100 ton><0.40><15,
000 BTU/hr.-ton><1 lb. water/1,000 BTU><2,000 hours><150
lbs. of scale/1,000,000 lbs. of water. Total annual scale accu
mulation:180 lbs. of scale for a 100 ton system operating at
40% load factor.
[0074] As can be appreciated from considering the above
example, water treatment is mandatory in order to sustain
system ef?ciency and minimize corrosion. To this end, with
used for evaporation for conventional air-cooled condensing
units 106 on residential or small commercial buildings and
facilities. As should be understood and appreciated herein,
pure rainwater will be free of dissolved minerals thus allow
ing the harvested rainwater to be sprayed, sprinkled, or oth
erwise, distributed over a ?nned air-cooled condensing coil
performed to minimize or eliminate the collection of sus
pended solids on the ?nned condensing coil 108 can be deter
mined on an individual basis as desired and therefore is not
intended to be limited herein.
[0078]
Inventive rooftop rainwater collection systems such
as is illustrated in FIG. 1 may utilize, but are not limited to the
use of, one or more of the following in order to limit the
introduction of suspended solids onto the ?nned condensing
coils 108: a) leaf screens; b) rainwater storage tank methods
for settling solids out of a water stream; c) gravity centrifugal
cyclone type separators; and d) cartridge or bag type ?lter
units. However, in accordance with certain embodiments
herein, a passive ?ltration process (e.g., solids settling, etc.)
may be utilized in which the owner/user periodically hoses or
sprays the condenser coils 108 to dislodge any solids that may
have collected. In accordance with one speci?c aspect of the
present disclosure, the effects of suspended solids in the col
lected rainwater can be minimized by ?ltering the rainwater
with a ?ltration device selected from a barrier ?ltration
device, a screen, a cartridge, a bag, a centrifugal separator
device and a settling ?ltration device.
regard to water treatment, bleed-off or blow down is a com
[0079] At peak air conditioning or refrigeration load, the
mon technique to try to minimize scale build-up. If you bleed
off an amount of water equal to the evaporation rate (this is
known as two cycles of concentration), the system would now
be exposed to double the amount of dissolved minerals.
water ?ow rate over the condenser coil 108 can be from about
Bleed-off is a form of dilution so as to not concentrate the
minerals.
[0075]
With two cycles of concentration, the system would
be exposed to 2.70 pounds of scale on a ten hour design day
(as illustrated above) and also 360 pounds of scale on an
annualized basis. Moreover, if a water treatment program is
95% effective in minimizing scale accumulation, 18 pounds
1.5 to about 10.0 gallons per hour per ton depending upon the
geometry of the coil and the speci?c characteristics of the air
conditioning or refrigeration system under consideration.
[0080] The evaporators of many air conditioning and
refrigeration systems condense moisture out of the air as part
of the dehumidifying effect of air conditioning. This con
densed water is distilled water which is suitable for an
ESRACHTS system. As seen in FIGS. 2 and 4, for instance,
in accordance with certain aspects of the present disclosure, it
is possible for the condensed water from the evaporator coil
Aug. 21,2014
US 2014/0231042 A1
drain pan to be introduced into the rainwater storage tank (see
reference numeral 202, which illustrates this process), and
particularly if the drain pan is located relative to the storage
tank 204, 404. According to this aspect of the present disclo
sure, the condensed water can then be used to supplement the
water accumulated from rainwater.
[0081] Referring once again to FIG. 1, since most air con
and installation of such a system. These illustrations are
merely provided to illustrate the various arrangements that
may be utilized in accordance with the teachings of the
present disclosure but are not intended to be limiting or all
inclusive in nature. Accordingly, those of skill in the art
should readily understand and appreciate herein that several
other different variations may also be utilized without stray
ditioning systems never operate at full load all of the time, the
ing from the teachings of the present disclosure, particularly
water ?ow rate over the coil 108 can be varied by use of a
as the basic ESRACHTS system concept is applicable to a
multitude of installations. It will be incumbent upon the
owner/purchaser/installer to follow the basic ESRACHTS
system concepts to install a workable system to achieve the
regulator device or control valve 110 that modulates in
response to condensing (head) pressure. Because this water is
mineral free, a variable water ?ow rate is allowed over the
condensing coil 108. This modulating control valve 110 can
serve to conserve the accumulated rainwater and also help
maintain a minimum head pressure on systems that require
some external head pressure control. In accordance with cer
tain aspects of the present disclosure, the regulator or control
valve 110 can be positioned between the storage tank 104 and
the liquid dispersion point 112 where the condensing head or
dispersion unit is con?gured to distribute rainwater onto the
condensing coil 108. Moreover, in accordance with still other
aspects of the present disclosure, regulating the amount or
quantity of rainwater that should be distributed by one or
more dispersion units onto the condensing coil 108 can be
desired energy savings.
[0088] Still referring to the illustrative embodiment of FIG.
1, ESRACHTS system 100 illustrates house roof 102 having
drains/gutters 114 that collect all roof water drainage and
allow it to be captured and stored in a rainwater tank 104
mounted on a stand 116 or elevated by some other method.
This elevated tank 104 can then allow rainwater to ?ow by
gravity into the condensing unit 1 06 water distribution system
112. This approach eliminates the need for a pump to deliver
water over the condenser coil 108. Excess water in the con
densing unit 106 can drain 118 into the storm sewer, into a
interpreted or determined by one or more sensors associated
ditch, or be used for lawn watering, etc., as allowed by regu
lations. It should be understood and appreciated herein that
with the regulator 110.
[0082] Since proper wetting of the condensing coil 108 is
essential to the energy ef?ciency inherent with evaporatively
with the storage tanks or reservoirs for transferring liquid to
cooled condensers 106, existing condensing unit installations
one or more conduits (e.g., pipes, tubes) can be associated
the liquid dispersion points proximate the condensing coils.
may require a modi?cation in order to accommodate sprays
As such, the speci?c method or process utilized for transfer
ring water from the storage unit to the dispersion unit is not
112, gravity distribution troughs, etc. As manufacturers of air
intended to be limited herein.
conditioning and refrigeration condensing units make design
modi?cations (internal water piping and sprays, etc.) to their
new units, installation of an ESRACHTS system will be much
easier to implement.
[0083]
Properly designed air-cooled condensers have air
?ow rates and coil face velocities such that water carry-over
(water being drawn through the fan 122) should not create
problems on existing installations. Again, proper water dis
tribution over the coil prevents water carry over.
[0084] The introduction of evaporative condensing to for
merly air-cooled condensing will reduce the peak KW energy
input per ton from 1.4 or 1.3 to 0.9 and possibly as low as 0.7
KW per ton. The speci?c energy reduction on existing con
densing units is largely dependent upon the original design of
the condensing unit (compressor type and ef?ciency, amount
of condensing surface, condenser fan performance, etc.).
[0085] Evaporative condensing achieved by wetting a
?nned air-cooled condenser coil 108 will reduce the design
condensing temperature from a range of about 115° F. to
about 130° F. to a range of about 90° F. to about 100° F. This
reduction in condensing temperature and corresponding con
densing pressure is the cause for the reduction in energy input
to the compressor. As this reduction of condensing tempera
ture and pressure becomes more commonplace, condensing
unit manufacturers will design and size condensing coils 108
[0089]
In accordance with another embodiment depicted in
FIG. 2, an ESRACHTS 200 is illustrated with an in-ground
storage tank 204 with a submersible pump 206 to deliver
water to the condensing unit 106 water distribution system
112. This system can allow for excess water to drain back 202
to the storage tank 204. If arranged properly, additional rain
water could be delivered from ground sources 208 into the
rainwater storage tank 204. This in-ground storage tank 204 is
much like in-ground sewage tanks that are commonly used in
many parts of the country.
[0090] FIG. 3 illustrates yet another embodiment where an
ESRACHTS 300 locates the storage tank 302 indoors above
grade and requires a pump 304 to deliver the rainwater to the
condensing unit 108 distribution system 112.
[0091] A further embodiment shown in FIG. 4 illustrates an
ESRACHTS 400 that locates the storage tank 404 below
grade and even possibly in a basement. A pump 402 is
required to deliver the rainwater to the condensing unit 106
distribution system 112. Ground-level drains could convey
the rainwater into the storage tank 404.
[0092] In all cases, it is important that the rainwater storage
tanks be vented to the outdoors 120. However, the decision as
to where the rainwater storage tank should be located and the
size of the tank will be determined by the site-speci?c factors,
and compressors to operate more ef?ciently at these new
and therefore is not intended to be limited herein.
operating conditions.
[0086] These lower condensing temperatures at peak sum
mer weather conditions (high dry bulb temperatures, high wet
bulb temperatures, and high relative humidity) can bene?t
[0093] If the accumulation of rainwater is achieved through
a gutter 114, it should be appreciated that some gutter and
downspout modi?cations may be required so as to maximize
the amount of rainwater that can be harvested. In addition,
electrical utilities by lowering their peak demand.
[0087] The illustrative ESRACHTS system con?gurations
shown in FIGS. 1-4 provide ?exibility for the arrangement
freezing damage, and it is recommended that all systems be
some systems may need to be drained in winter to avoid
cleaned at least twice a year (prior to air conditioning season
Aug. 21,2014
US 2014/0231042 A1
and at the conclusion of air conditioning season) if the air
conditioning is a seasonably operated unit.
[0094] FIG. 5 depicts an ESRACHTS system 500 having a
traditional air-cooled condensing unit 106. In accordance
with this embodiment, the unit 106 is fully functional in the
event that insu?icient rainwater has been accumulated due to
drought, equipment failure, or human error. Accordingly, the
system ef?ciency will be the same as the conventional air
cooled system. The ESRACHTS System 500 is unique from
other systems that might want to achieve low condensing
temperatures, particularly since these systems do not use
rainwater to wet a standard condensing coil to achieve low
[0100]
On large commercial and industrial systems, the
water usage for evaporation can far exceed a rainwater har
vesting system’s ability. As an example, a 500 ton water
cooled or evaporatively cooled system would require a peak
water usage for evaporation of 15 GPM of water. For a 40%
load factor, the monthly water usage for evaporation only
would be 260,000 gallons. As an example, using rain fall
averages from The National Oceanic and Atmospheric
Administration (NOAA), 2.64 inches of rain will fall in
Columbia, Mo. for the month of March. A 1,900 square foot
home with a slanted roof can collect 2,500 gallons in the
month. This size of home could equate to a 5-ton air condi
ESRACHTS System. For instance, low condensing tempera
tioning load. By extrapolation, the amount of square footage
required to accumulate 260,000 gallons of water (500 ton
system) via rainwater harvesting would be nearly 200,000
tures on residential air conditioning systems can approximate
square feet.
or be equal to the energy ef?ciency (low KW-per-ton) of large
commercial or industrial air conditioning systems. Moreover,
[0101] This square footage of building area along with the
infrastructure (rainwater tank size, guttering and piping to
handle this volume of water) makes rainwater harvesting
condensing.
[0095]
There are many non-limiting bene?ts of the
the use of mineral-free rainwater to facilitate the low KW-per
ton air conditioning systems is unique because large systems
seem like an unworkable and virtually an impossible idea to
would require such an enormous volume of stored rainwater
that such a system would not be feasible. To this end, the
be considered.
rainwater, without dissolved minerals, makes it feasible to
achieve evaporative heat rejection with current, standard
design air cooled condensers and condensing units. Addition
ally, since existing homes and residences already have a gut
ter and drain system to handle rainwater, modi?cations on a
system-to-system basis may not require a signi?cant expense
[0102] Furthermore, if a water source other than rainwater
were to be considered (well water or city water), the cost of
pumping or purchasing that water and disposing of that water
could be costly. Also, the treating of that water so as to
minimize the effects of scaling of the condenser coil makes
this an unworkable idea.
to harvest and store rainwater.
[0103]
[0096] Many rainwater harvesting systems try to store and
supply enough water that may be required for irrigation sys
reduce condensing temperatures, residentially, (although not
extensively) employ the adiabatic saturation of air 700 (FIG.
tems and domestic water supplies in areas that typically have
insuf?cient water to sustain normal life. These rainwater har
vesting systems can be massive and not feasible. However,
7) to reduce the dry bulb air temperature entering a ?nned
condenser coil on air conditioning systems. This method is
harvesting enough rainwater to permit evaporative heat trans
Most existing technologies that are used to try to
used so that water will not directly come in contact with a
?nned condenser coil subjecting it to the scaling effect result
ing from use of city or well water. However, the air saturating
fer for residences can be quite feasible.
[0097] In the event of a drought or insuf?cient rainwater
media can become scaled using city or well water and cause
storage required for ef?cient air conditioning operation, the
maintenance and operating problems. Likewise, overspray of
air conditioner will merely operate as air-cooled only, allow
ing for continued air conditioning albeit at a higher KW per
ton than the ESRACHTS system.
this water will also scale and clog the condenser coil, which is
[0098]
Existing large refrigeration systems will use evapo
an unintended consequence.
[0104] The ESRACHTS System uses rainwater directly on
a ?nned condenser coil allowing the refrigerant to give up its
rative condensers where water is sprayed over an all-prime
latent heat in condensing from a gas to a liquid while the
surface (non-?nned) condensing coil to permit low condens
mineral-free rainwater evaporates allowing the heat to dissi
ing temperatures. These systems will use a recirculating spray
pate into the air in the form of a vapor.
water system with make-up water being supplied from city
water or well water systems. One-hundred percent rainwater
is not a viable option due to the large volume of rainwater that
would have to be harvested. Some evaporative condenser
systems utilize wide-spaced ?nned coils so that dry operation
of these condensers can be achieved during low ambient
outdoor weather. Most of these systems (only a very few
exist) operate unsuccessfully since the ?ns get scaled-up from
the use of city or well water make-up4even in the presence of
a good water treatment system.
[0099] There are products that try to saturate the air adia
[0105]
FIGS. 6 and 7 are provided herein to illustrate the
thermodynamics of conventional air cooled condensing 600
and adiabatic condensing 700. Unlike these traditional sys
tems, the ESRACHTS System utilizes a unique con?guration
and process to lower condensing temperatures on residential
and small commercial systems. For instance, taking the
example ofa 5 ton residence (1,900 sq. ft.) in Columbia, Mo.
where 2,500 gallons can be accumulated in one month, at a
peak summer cooling load of 5 tons and at a monthly average
load of 50%, the monthly heat rejection would amount to: 5
batically before that air reaches the ?nned condensing coil to
tons><15,000 BTU/hr/tonx0.5><24 hours/day><30 days/
avoid scaling (see system 700 illustrated in FIG. 7). This
system is fundamentally different from the ESRACHTS Sys
evaporated would be: 27,000,000 BTU/ 1,000 BTU/1b.:27,
tem. Again, the ESRACHTS system wets a standard copper
coil aluminum-?nned condenser coil with mineral-free rain
month:27,000,000 BTU/month. The amount of water to be
000 lb./month. This equates to 3,200 gallons per month of
water to account for evaporation.
water which thereby permits low condensing temperatures
[0106]
and low energy usage without scaling the ?nned condenser
coil.
mulate 2,500 gallons. Therefore, a maximum storage volume
In Columbia, Mo., a 1,900 sq. ft. house can accu
to accommodate an extremely hot month could require a
Aug. 21,2014
US 2014/0231042 A1
3,000 to 4,000 gallon tank. As an example, a cylindrical tank
8' diameter><8' tall would have a gross volume of 3,000 gal
lons.
[0107] Although the primary focus of an ESRACHTS Sys
tem is residential air conditioning and refrigeration, all of the
concepts are applicable to larger commercial and industrial
applications with the limitations being that of the ability to
element or feature’s relationship to another element(s) or
feature(s) as illustrated in the ?gures. Spatially relative terms
may be intended to encompass different orientations of the
device in use or operation in addition to the orientation
depicted in the ?gures. For example, if the device in the
?gures is turned over, elements described as “below” or
“beneath” other elements or features would then be oriented
harvest and store the rainwater.
“above” the other elements or features. Thus, the example
[0108] While an exemplary embodiment incorporating the
principles of the present application has been disclosed here
inabove, the present application is not limited to the disclosed
term “below” can encompass both an orientation of above and
embodiments. Instead, this application is intended to cover
any variations, uses, or adaptations of the application using its
general principles. Further, this application is intended to
cover such departures from the present disclosure as come
within known or customary practice in the art to which this
present applicationpertains and which fall within the limits of
the appended claims.
[0109] The terminology used herein is for the purpose of
describing particular illustrative embodiments only and is not
intended to be limiting. As used herein, the singular forms
“a”, “an” and “the” may be intended to include the plural
forms as well, unless the context clearly indicates otherwise.
The terms “comprises,” “comprising,” “including,” and “hav
ing,” are inclusive and therefore specify the presence of stated
features, integers, steps, operations, elements, and/or compo
nents, but do not preclude the presence or addition of one or
more other features, integers, steps, operations, elements,
components, and/or groups thereof. The method steps, pro
below. The device may be otherwise oriented (rotated 90
degrees or at other orientations).
1. An evaporative air conditioning heat transfer apparatus
comprising:
a collection surface for diverting liquid into a channel;
a reservoir capable of receiving and storing the diverted
liquid;
at least one conduit for transferring liquid from the reser
voir to a liquid dispersion point; and
a regulator positioned between the reservoir and the liquid
dispersion point, the regulator being con?gured to con
trol the amount of liquid released at the liquid dispersion
point,
wherein the liquid dispersion point is con?gured to distrib
ute the liquid over a condensing coil.
2. The evaporative air conditioning heat transfer apparatus
of claim 1, wherein the regulator is a valve or a pump.
3. The evaporative air conditioning heat transfer apparatus
of claim 1, wherein the collection surface is a roof.
4. The evaporative air conditioning heat transfer apparatus
cesses, and operations described herein are not to be con
of claim 3, wherein the channel is a gutter.
strued as necessarily requiring their performance in the par
ticular order discussed or illustrated, unless speci?cally
of claim 1, wherein the at least one conduit is a pipe.
identi?ed as an order of performance. It is also to be under
6. The evaporative air conditioning heat transfer apparatus
of claim 1, wherein the liquid is substantially mineral free
stood that additional or alternative steps may be employed.
[0110] When an element or layer is referred to as being
“on”, “engaged to”, “connected to” or “coupled to” another
element or layer, it may be directly on, engaged, connected or
coupled to the other element or layer, or intervening elements
or layers may be present. In contrast, when an element is
5. The evaporative air conditioning heat transfer apparatus
rainwater.
7. The evaporative air conditioning heat transfer apparatus
of claim 1, wherein the liquid dispersion point is positioned
proximate the condensing coil.
8. The evaporative air conditioning heat transfer apparatus
ment or layer, there may be no intervening elements or layers
of claim 1, further comprising a controller that is con?gured
to mechanically or electronically drive the regulator.
9. A method for cooling refrigeration condensing coils
present. Other words used to describe the relationship
between elements should be interpreted in a like fashion (e.g.,
“between” versus “directly between,” “adjacent” versus
?uidly coupling the reservoir to one or more dispersion
referred to as being “directly on,” “directly engaged to”,
“directly connected to” or “directly coupled to” another ele
“directly adjacent,” etc.). As used herein, the term “and/or”
includes any and all combinations of one or more of the
associated listed items.
[0111]
Although the terms ?rst, second, third, etc. may be
used herein to describe various elements, components,
regions, layers and/or sections, these elements, components,
regions, layers and/or sections should not be limited by these
comprising:
collecting rainwater in a reservoir;
units;
distributing the rainwater from the one or more dispersion
units onto a condensing coil of an air conditioning unit;
and
regulating the amount of rainwater distributed by the one or
more dispersion units onto the condensing coil.
10. The method of claim 9, further comprising positioning
terms. These terms may be only used to distinguish one ele
the reservoir above the one or more dispersion units to permit
ment, component, region, layer or section from another
region, layer or section. Terms such as “?rst,” “second,” and
gravity to provide suf?cient water ?ow and pressure for dis
tributing the rainwater onto the condensing coil from the one
other numerical terms when used herein do not imply a
sequence or order unless clearly indicated by the context.
or more dispersion units.
Thus, a ?rst element, component, region, layer or section
the reservoir below the one or more dispersion units and using
a pump to provide suf?cient water ?ow and pressure for
discussed below could be termed a second element, compo
11. The method of claim 9, further comprising positioning
nent, region, layer or section without departing from the
teachings of the example embodiments.
[0112] Spatially relative terms, such as “inner, outer,”
distributing the rainwater onto the condensing coil from the
“beneath”, “below”, “lower”, “above”, “upper” and the like,
and returning excess rainwater to the reservoir after the rain
water has been distributed onto the condensing coil.
may be used herein for ease of description to describe one
one or more dispersion units.
12. The method of claim 9, further comprising collecting
Aug. 21,2014
US 2014/0231042 A1
13. The method of claim 9, wherein the step of regulating
the amount of rainwater distributed by the one or more dis
17. A system for cooling refrigeration condensing coils
comprising:
persion units onto the condensing coil comprises interpreting
a reservoir for receiving and storing rainwater;
one or more sensors to determine when to distribute the
at least one conduit connected to the reservoir for transfer
rainwater onto the condensing coil.
14. The method of claim 9, wherein the step of regulating
a regulator having a controller that is con?gured to distrib
the amount of rainwater distributed by the one or more dis
persion units onto the condensing coil comprises determining
what quantity of rainwater is required to achieve a desired
condensing temperature.
15. The method of claim 9, further comprising the step of
minimizing effects of suspended solids in the rainwater.
16. The method of claim 15, wherein the step of minimiZ
ing effects of suspended solids in the rainwater comprises
?ltering the rainwater with a ?ltration device selected from a
barrier ?ltration device, a screen, a cartridge, a bag, a cen
trifugal separator device and a settling ?ltration device.
ring the rainwater to a liquid dispersion point; and
ute a speci?c amount of the rainwater over a condensing
coil from the dispersion point.
18. The system of claim 17, wherein the regulator is a valve
or a pump.
19. The system of claim 17, further comprising one or more
sensors for determining when to distribute the rainwater over
the condensing coil.
20. The system of claim 17, wherein the at least one conduit
is a pipe.