Note: Descriptions are shown in the official language in which they were submitted.
CA 02855767 2014-05-13
[ DESCRIPTION]
[Invention Title]
HOT WATER HEAT EXCHANGER
[Technical Field]
The present invention relates to a hot water heat exchanger, and more
particularly, to a hot water heat exchanger which supplies hot water through
heat
exchange between direct water and heating water heated in a main heat
exchanger of
a boiler.
[Background Art]
FIG. 1 is a block diagram schematically illustrating a general instantaneous
boiler for heating and hot water supply.
In a heating mode, a circulation pump 10 is operated and heating water is
transferred. The heating water is heated in a main heat exchanger 20 by
combustion
heat of a burner 21, and then transferred to a place to be heated through a
three-way
valve 30, whereby the heating is achieved. The heating water of which a
temperature is lowered by the heat exchange in the place to be heated is
transferred
to the main heat exchanger 20 through an expansion tank 50 and the circulation
pump 10 and then reheated. A reference numeral 22 which is not described is an
air
blower.
In a hot water mode, a passage connected from the three-way valve 30 to the
place to be heated is blocked, and a passage connected to a hot water heat
exchanger
40 is opened so that the heating water heated in the main heat exchanger 20 is
transferred to the hot water heat exchanger 40. In the hot water heat
exchanger 40,
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heat exchange between direct water and heating water is performed, and thus
heated
hot water is supplied to a place requiring the hot water.
Like this, the hot water heat exchanger 40 is connected with a pipe 41
through which the heating water is introduced, a pipe 42 through which the
heating
water is discharged, a pipe 43 through which the direct water is introduced,
and a
pipe 44 through which the hot water is discharged. To simplify a structure of
these
pipes 41, 42, 43 and 44, there has been proposed a hot water heat exchanger
which is
disclosed in Korean Patent No. 10-1002382 filed and registered by the
applicant.
The hot water heat exchanger disclosed in Korean Patent No. 10-1002382
includes a heat exchanging part in which a plurality of partitions are
arranged to
overlap, and the heating water and the direct water flow through spaces among
the
partitions, and thus the heat exchange is performed therebetween, a first
adaptor in
which an inlet port through which the heating water is introduced and an
outlet port
through which the heating water heat-exchanged in the heat exchanging part is
discharged are integrally formed and coupled to the heat exchanging part, and
a
second adaptor in which an inlet port through which the direct water is
introduced
and an outlet port through which hot water heated by the heat exchange with
the
heating water in the heat exchanging part is discharged are integrally formed
and
coupled to the heat exchanging part.
In the heat exchanging part, passages of the heating water and the direct
water are defined by a space between adjacent partitions. These passages have
longer lengths and smaller cross-sectional areas than those in a general hot
water heat
exchanger, and thus flow resistance in the heat exchanging part becomes much
larger.
[Disclosure]
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[Technical Problem]
The present invention is directed to providing a hot water heat exchanger
which has a simple piping structure and minimizes a flow passage length
therein,
thereby minimizing flow resistance.
[Technical Solution]
One aspect of the present invention provides a hot water heat exchanger
including a heat exchanging part (100) in which a plurality of partitions (101
to 113)
are arranged to overlap, and heating water supplied from a main heat exchanger
and
direct water alternately flow through spaces (131, 132, 133 and 134) among the
partitions, and thus heat exchange is achieved therebetween, a first adaptor
(210) in
which an inlet port (211) through which the heating water is introduced and an
outlet
port (212) through which the heating water heat-exchanged in the heat
exchanging
part (100) is discharged are integrally formed and coupled to the heat
exchanging
part (100), and a second adaptor (220) in which an inlet port (221) through
which the
direct water is introduced and an outlet port (222) through which hot water
heat-
exchanged with the heating water and thus heated in the heat exchanging part
(100)
is discharged are integrally formed and coupled to the heat exchanging part
(100),
wherein the first adaptor (210) and the second adaptor (220) are connected to
the
partition (101) configured to define one side surface of the heat exchanging
part
(100), a first heating water circulation passage (131) through which the
heating water
introduced from the inlet port (211) of the first adaptor (210) flows is
formed at the
space between the partition (101) and the partition (102) adjacent thereto, a
first
direct water circulation passage (133) through which the direct water
introduced
from the inlet port (221) of the second adaptor (220) flows is formed at the
space
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between the partition (113) configured to define the other side surface of the
heat
exchanging part (100) and the partition (112) adjacent thereto, and a
plurality of
second heating water circulation passages (132) through which the heating
water
passing through the first heating water circulation passage (131) flows, and a
plurality of second direct water circulation passages (134) through which the
direct
water passing through the first direct water circulation passage (133) flows
are
alternately formed between the first heating water circulation passage (131)
and the
first direct water circulation passage (133).
[Advantageous Effects]
According to the present invention, since the heating water introduced
through the first adaptor is introduced into the first heating water
circulation passage
formed at one side of the heat exchanging part, and the direct water
introduced
through the second adaptor is introduced into the first direct water
circulation
passage formed at the other side of the heat exchanging part, the flow
passages of the
heating water and the direct water, which are formed in the heat exchanging
part,
may be shortened.
Further, since the heating water passing portion having the expanded flow
cross-sectional area is formed at the partition disposed at one side of the
heat
exchanging part, and the direct water passing portion having the expanded flow
cross-sectional area is formed at the partition disposed at the other side of
the heat
exchanging part, the flow resistance may be reduced.
[Description of Drawings]
FIG. 1 is a block diagram schematically illustrating a general instantaneous
boiler for heating and hot water supply.
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FIG. 2 is a perspective view of a hot water heat exchanger according to the
present invention.
FIG. 3 is an exploded perspective view of the hot water heat exchanger of
FIG. 2.
FIG. 4 is a schematic cross-sectional view taken along a line A-A of a heat
exchanging part of the hot water heat exchanger of FIG. 2.
FIG. 5 is a schematic cross-sectional view taken along a line B-B of the heat
exchanging part of the hot water heat exchanger of FIG. 2.
FIG. 6 is a cross-sectional view illustrating a state in which a first
connection
member and a second connection member are coupled to a first adaptor according
to
the present invention.
FIG. 7 is a cross-sectional view illustrating a state in which a third
connection
member and a fourth connection member are coupled to a second adaptor
according
to the present invention.
FIG. 8 is a cross-sectional view respectively illustrating a passage of
heating
water and a passage of hot water in a state in which the first and second
adaptors are
coupled to the heat exchanging part according to the present invention.
[Description of Main Elements]
1: hot water heat exchanger 100: heat exchanging part
101 to 113: partition
101a to 111a, 102b to 111 b: heating water passing hole
101c to 112c, 103d to 112d: direct water passing hole
131: first heating water circulation passage
132: second heating water circulation passage
133: first direct water circulation passage
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134: second direct water circulation passage
210: first adaptor 211: inlet port
212: outlet port 213: external connection port
214: internal connection port 216: feed water valve connection port
217: returning heating water connection port 220: second adaptor
221: inlet port 222: outlet port
223: internal connection port 224: external
connection port
226: feed water valve connection port 231: first connection member
232: second connection member 233: third
connection member
234: fourth connection member 300: feed water valve
[Modes of the Invention]
Hereinafter, the configurations and operations of exemplary embodiments of
the present invention will be described in detail with reference to the
accompanying
drawings.
FIG. 2 is a perspective view of a hot water heat exchanger according to the
present invention.
A hot water heat exchanger 1 according to the present invention includes a
heat exchanging part 100 in which a plurality of partitions are arranged to
overlap,
and heating water and direct water flow through spaces among the partitions,
and
thus heat exchange is achieved therebetween, and a first adaptor 210 and a
second
adaptor 220 coupled to the heat exchanging part 100 to connect the heat
exchanging
part 100 and pipes 41, 42, 43 and 44 (FIG. 1) of a heating line and a hot
water line.
FIG. 3 is an exploded perspective view of the hot water heat exchanger of
FIG. 2, FIG. 4 is a schematic cross-sectional view taken along a line A-A of a
heat
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exchanging part of the hot water heat exchanger of FIG. 2, and FIG. 5 is a
schematic
cross-sectional view taken along a line B-B of the heat exchanging part of the
hot
water heat exchanger of FIG. 2.
As an example, the heat exchanging part 100 is configured with a structure in
which thirteen partitions 101 to 113 overlap. The partitions 101 to 113 serve
as
heat transfer surfaces on which the heat exchange between the heating water
and the
direct water is performed, and have a stacking structure in which edge
portions of
thin plates are bent and the edge portions of the adjacent partitions 101 to
113 are
welded and coupled to each other.
The partitions 101 to 113 have concavo-convex portions to increase a heat
transfer area. The concavo-convex portions are omitted in FIGS. 4 and 5.
The partitions 101 to 113 define heating water passing holes 101a to 112a and
102b to 111b and direct water passing holes 101c to 112c and 103d to 112d
through
which the heating water and the direct water may flow in the heat exchanging
part
100 without being mixed.
The heating water passing holes 101a to 112a and 102b to 111b and the direct
water passing holes 101c to 112c and 103d to 112d may be defined by protruding
and also bending flat portions of the partitions 101 to 113 to form flanges,
and thus
the partitions may be coupled so that the heating water passing holes and the
direct
water passing holes of the adjacent partitions are respectively in
communication with
each other. As illustrated in FIGS. 4 and 5, the flange shapes protruding
around the
heating water passing holes and the direct water passing holes may be formed
on the
adjacent partitions. Otherwise, only the holes may be formed in one partition,
and
the flanges may be formed on another adjacent partition by protruding the
holes.
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The heating water passing holes 101a to 112a and 102b to 111b connected as
described above form a passage through which the heating water flows, and the
direct water passing holes 101c to 112c and 103d to 112d form a passage
through
which the direct water flows.
As illustrated in FIGS. 4 and 5, the space formed among the partitions 101 to
113 defines heating water circulation passages 131 and 132 and direct water
circulation passages 133 and 134. The heating water introduced into the heat
exchanging part 100 through the first adaptor 210 passes, in turn, through the
first
heating water circulation passage 131 and the second heating water circulation
passage 132, and is heat-exchanged with the direct water passing through the
first
direct water circulation passage 133 and the second direct water circulation
passage
134, and then discharged to a heating water returning side through the first
adaptor
210. Further, the direct water introduced into the heat exchanging part 100
through
the second adaptor 220 passes, in turn, through the first direct water
circulation
passage 133 and the second direct water circulation passage 134, and is heat-
exchanged with the heating water passing through the first heating water
circulation
passage 131 and the second heating water circulation passage 132, and then
supplied
to a place requiring hot water through the second adaptor 220.
A heating water passing portion 101e is provided at the partition 101, to
which the adaptors 210 and 220 are coupled, to protrude toward an outside of
the
heat exchanging part 100 and also to diagonally cross the partition 101. A
space
formed between the first partition 101 having the heating water passing
portion 101e
and another adjacent partition 102 defines the first heating water circulation
passage
131. The concavo-convex portions are formed on the adjacent partition 102. In
this case, since the remaining flat portion of the partition 101 other than
the heating
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water passing portion 101e may be in contact with or close to the concavo-
convex
portions formed at the adjacent partition 102, flow resistance may be
increased when
the heating water passes through this area. In the present invention, since
the
heating water passing portion 101e is formed to protrude to the outside, and
the
heating water passing hole 101a through which the heating water is introduced
is
formed at one end of the heating water passing portion 101e, the heating water
may
be led to the heating water passing portion 101e having the expanded passage,
and
thus the flow resistance is reduced when the heating water passes.
Meanwhile, a direct water passing portion 113e is provided at another
partition 113, which is disposed at the other side of the heat exchanging part
100 to
be opposite to the first partition 101, to protrude toward the outside of the
heat
exchanging part 100 and also to diagonally cross the other partition 113. A
space
formed between the partition 113 having the direct water passing portion 113e
and
another partition 112 adjacent thereto defines the first direct water
circulation
passage 133. Since the passage is expanded due to the direct water passing
portion
113e, the flow resistance is reduced when the direct water passes through the
first
direct water circulation passage 133.
FIG. 6 is a cross-sectional view illustrating a state in which a first
connection
member and a second connection member are coupled to a first adaptor according
to
the present invention, and FIG. 7 is a cross-sectional view illustrating a
state in
which a third connection member and a fourth connection member are coupled to
a
second adaptor according to the present invention.
A coupling structure between the heat exchanging part 100 and the first
adaptor 210 will be described with reference to FIG. 6.
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An end of a first connection member 231 is inserted and coupled into the
heating water passing hole 101a formed in the first partition 101. The first
connection member 231 has a cylindrical body, and an upper end of the body is
bent,
and the bent portion is inserted into and welded to the heating water passing
hole
101a.
A second connection member 232 is inserted into the first connection
member 231. The second connection member 232 has a body which partly
protrudes to an upper side of the first connection member 231, and an upper
end of
the protruding portion is inserted and coupled into the heating water passing
holes
102b and 103b of the second and third partitions 102 and 103.
An inner circumferential surface of the first connection member 231 and an
outer circumferential surface of the second connection member 232 are spaced
apart
from each other, and the heating water introduced through an inlet port 211
passes
through a space 231a formed therebetween.
The first adaptor 210 connects a heating water pipe and the heat exchanging
part 100 so that the heating water is introduced or discharged therethrough.
The
inlet port 211, an outlet port 212 and connection ports 213 and 214 are
integrally
formed by an injection molding process.
The inlet port 211 is connected with the pipe 41 of the heating line in FIG. 1
so that the heating water is introduced therethrough, and the outlet port 212
is
connected with the pipe 42 of the heating line in FIG. 1 so that the heating
water
passing through the heat exchanging part 100 is discharged through the outlet
port
212.
The connection ports 213 and 214 include an external connection port 213
inserted and coupled into a lower end of the first connection member 231, and
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internal connection port 214 inserted and coupled into a lower end of the
second
connection member 232. The internal connection port 214 is concentrically
disposed in the external connection port 213.
The heating water introduced through the inlet port 211 passes through a
The heating water circulated in the heat exchanging part 100 passes through
An 0-ring configured to maintain airtightness may be inserted into a coupling
portion between the first connection member 231 and the external connection
port
213 and a coupling portion between the second connection member 232 and the
In a state in which the external connection port 213 and the internal
connection port 214 are inserted into the lower ends of the first and second
connection members 231 and 232 through the 0-ring, if the external connection
port
213 and a protruding outer circumferential surface of the first connection
member
In this case, since the upper end of the first connection member 231 is welded
around the heating water passing hole 101c of the partition 101, and the upper
end of
the second connection member 232 is welded around the heating water passing
holes
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102b and 103b of the partitions 102 and 103, only the first adaptor 210 may be
separated from the first and second connection members 231 and 232.
Meanwhile, a feed water valve connection port 216 (referring to FIG. 8)
connected with a feed water valve 300 (referring to FIG. 8) configured to
replenish
the heating water into the heating water pipe of a boiler may be formed at the
first
adaptor 210. The feed water valve 300 serves to additionally supply the
heating
water when the heating line lacks the heating water. Since the feed water
valve 300
is connected to the feed water valve connection port 216 which is integrally
formed
at the first adaptor 210, the piping structure may be simplified.
Further, a returning heating water connection port 217 (referring to FIG. 8)
may be provided at the first adaptor 210. The returning heating water
connection
port 217 is connected to the heating water pipe side in which the returning
heating
water flows. The returning heating water introduced through the returning
heating
water connection port 217 is supplied to a circulation pump 10 through the
outlet
port 212.
A coupling structure between the heat exchanging part 100 and the second
adaptor 220 will be described with reference to FIG. 7.
A third connection member 241 is inserted and coupled into the direct water
passing holes 101c and 102c formed in the first and second partitions 101 and
102.
The third connection member 241 has a cylindrical body, and an upper end of
the
body is bent, and the bent portion is inserted into and welded to the direct
water
passing holes 101c and 102c.
A fourth connection member 242 is inserted into the third connection member
241. The fourth connection member 242 has a body which partly protrudes to an
upper side of the third connection member 241, and an upper end of the
protruding
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portion is coupled around the direct water passing holes 111c and 112c of the
partitions 111 and 112 disposed at an upper side of the heat exchanging part
100.
An inner circumferential surface of the third connection member 241 and an
outer circumferential surface of the fourth connection member 242 are spaced
apart
from each other, such that a space 241a formed therebetween is in
communication
with the outlet port 222.
The second adaptor 220 connects the direct water/hot water pipe 43 or 44 and
the heat exchanging part 100 so that the direct water/hot water is introduced
or
discharged therethrough. An inlet port 221, an outlet port 222 and connection
ports
223 and 224 are integrally formed by an injection molding process.
The inlet port 221 is connected with the pipe 43 of FIG. 1 so that the direct
water is introduced therethrough, and the outlet port 222 is connected with
the pipe
44 of FIG. 1 so that the heating water heated while passing through the heat
exchanging part 100 is discharged therethrough.
The connection ports 223 and 224 include an external connection port 224
inserted and coupled into a lower end of the third connection member 241, and
an
internal connection port 223 inserted and coupled into a lower end of the
fourth
connection member 242. The internal connection port 223 is concentrically
disposed in the external connection port 224.
The direct water introduced through the inlet port 221 is introduced into the
first direct water circulation passage 133 through inner spaces of the
internal
connection port 223 and the fourth connection member 242.
The direct water circulated in the heat exchanging part 100 through the first
direct water circulation passage 133 passes, in turn, through a space 241a
formed
between the third connection member 241 and the fourth connection member 242
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and a space 225 formed between the external connection port 224 and the
internal
connection port 223 and in communication with the space 241a, and then is
discharged through the outlet port 222.
An 0-ring configured to maintain airtightness may be inserted into a coupling
portion between the third connection member 241 and the external connection
port
224 and a coupling portion between the fourth connection member 242 and the
internal connection port 223.
In a state in which the external connection port 224 and the internal
connection port 223 are inserted into the lower ends of the third and fourth
connection members 241 and 242 through the 0-ring, if the external connection
port
224 and a protruding outer circumferential surface of the third connection
member
241 are fixed to each other by a clamp or the like, the second adaptor 220 may
be
removable.
In this case, since the upper end of the third connection member 241 is
welded around the passing holes 101c and 102c of the partitions 101 and 102,
and
the upper end of the fourth connection member 242 is welded around the passing
holes 111c and 112c of the partitions 111 and 112, only the second adaptor 220
may
be separated from the third and fourth connection members 241 and 242.
As described above, since the inlet ports 211 and 221, the outlet ports 212
and 222 and the connection ports 213, 214, 223 and 224 are integrally formed
at the
first and second adaptors 210 and 220 of the present invention, the piping
structure
may be simplified.
A feed water valve connection port 226 (referring to FIG. 8) connected with
the feed water valve 300 may be provided at the second adaptor 220.
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FIG. 8 is a cross-sectional view respectively illustrating a passage of
heating
water and a passage of hot water in a state in which the first and second
adaptors are
coupled to the heat exchanging part according to the present invention.
The first and second adaptors 210 and 220 configured to connect the heating
water pipe and the hot water pipe are coupled to the heat exchanging part 100,
and
the first adaptor 210 and the heat exchanging part 100 are coupled to each
other
through the first connection member 231 and the second connection member 232.
When the three-way valve 30 is switched into a hot water mode, the heating
water heated in the main heat exchanger 20 does not flow to a place to be
heated, but
is supplied to the hot water heat exchanger 1 and introduced into the inlet
port 211 of
the first adaptor 210.
The heating water introduced from the inlet port 211 of the first adaptor 210
passes, in turn, through the space 215 between the external connection port
213 and
the internal connection port 214 of the first adaptor 210 and the space 231a
between
the first connection member 231 and the second connection member 232 and then
introduced into the first heating water circulation passage 131 formed between
the
first partition 101 and the adjacent partition 102.
Since the upper end of the second connection member 232 is coupled so that
the heating water is not introduced into the heating water passing holes 102b
and
103b of the partitions 102 and 103, the heating water introduced into the
first heating
water circulation passage 131 horizontally flows along the first heating water
circulation passage 131, and then is introduced into the upper heating water
circulation passage through other heating water passing holes 102a and 103a
which
are diagonally formed with respect to the heating water passing holes 102b and
103b.
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Since the heating water passing portion 101e having the expanded flow cross-
sectional area is formed at the partition 101 defining the first heating water
circulation passage 131, the flow resistance is not greatly applied to the
heating water
passing through the first heating water circulation passage 131.
The heating water passing through the heating water passing holes 102a and
103a passes, in turn, through the heating water passing holes 104a to 111a of
another
partition formed immediately thereabove, and then horizontally flows through a
plurality of second heating water circulation passages 132 formed above the
first
heating water circulation passage 131 in a direction opposite to the flow
direction in
the first heating water circulation passage 131.
The heating water heat-exchanged with the direct water passing through the
direct water circulation passages 133 and 134 while passing through the second
heating water circulation passage 132 passes, in turn, through the heating
water
passing holes 111b to 104b formed in a diagonally horizontal direction of the
heating
water passing holes 104a to 111a, and then is discharged to the expansion tank
50
through the outlet port 212 in a state in which a temperature thereof is
lowered while
being introduced into the second connection member 232 and passing through the
internal connection port 214 of the first adaptor 210.
At the same time, the direct water is introduced into the inlet port 221 of
the
second adaptor 220. The direct water introduced into the inlet port 221 passes
through the inner sides of the internal connection port 223 and the fourth
connection
member 242, and then is introduced into the first direct water circulation
passage 133
formed at an opposite side of the heat exchanging part 100 to which the
adaptors 210
and 220 are coupled.
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The direct water introduced into the first direct water circulation passage
133
flows horizontally and then is introduced into the lower direct water
circulation
passage through the direct water passing holes 111d and 112d formed in the
partitions 111 and 112.
Since the direct water passing portion 113e having the expanded flow cross-
sectional area is formed at the partition 113 defining the first direct water
circulation
passage 133, the flow resistance is not greatly applied to the direct water
passing
through the first direct water circulation passage 133.
The direct water passing through the passing holes 111d and 112d passes, in
turn, through the direct water passing holes 110d to 103d of another partition
formed
immediately therebelow, and then horizontally flows through a plurality of
second
direct water circulation passages 134 formed below the first direct water
circulation
passage 133 in a direction opposite to the flow direction in the first direct
water
circulation passage 133.
The direct water heat-exchanged with the heating water passing through the
heating water circulation passages 131 and 132 while passing through the
second
direct water circulation passage 134 passes, in turn, through the direct water
passing
holes 110c to 103c formed in a diagonally horizontal direction of the direct
water
passing holes 110d to 103d, and then is discharged to the place requiring hot
water
through the outlet port 222 in a state of being changed into the hot water
while being
introduced into the space 241a between the third connection member 241 and the
fourth connection member 242 and passing through the space 225 between the
internal connection port 223 and the external connection port 224.
In this case, the fourth connection member 242 is inserted into the direct
water passing holes 110c to 103c, and the direct water flows through an
interval
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between an outer circumferential surface of the fourth connection member 242
and
the direct water passing holes 110c to 103c.
In the present invention, as described above, since one first heating water
circulation passage 131, the plurality of second direct water circulation
passages 134,
the plurality of second heating water circulation passages 132 and one first
direct
water circulation passage 133 are stacked in turn, the flow passages of the
heating
water and the direct water flowing in the heat exchanging part 100 are short,
and thus
the flow resistance is reduced.
That is, since the first heating water circulation passage 131 serving as the
first space in the heat exchanging part 100 in which the heating water is
introduced,
and the first direct water circulation passage 133 serving as the first space
in the heat
exchanging part 100 in which the direct water is introduced are respectively
formed
at one side and the other side of the heat changing part 100, the flow
passages of the
heating water and the direct water may be shortened.
Meanwhile, when the three-way valve 30 is switched into a heating mode, the
heating water supplied to the place to be heated performs the heat exchanging
process and then is returned to the circulation pump 10. In the present
invention,
the returning heating water returned to the circulation pump 10 is introduced
into the
returning heating water connection port 217 of the first adaptor 210, and then
returned to the circulation pump 10 through the outlet port 212 and the
expansion
tank 50.
If the heating line lacks the heating water, the feed water valve 300 is
opened
to replenish the heating water. The feed water valve 300 is installed between
the
feed water valve connection port 216 of the first adaptor 210 and the feed
water
valve connection port 226 of the second adaptor 220. Therefore, if the feed
water
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valve 300 is opened, some of the hot water in the second adaptor 220 passes,
in turn,
through the feed water valve connection port 226, the feed water valve
connection
port 216 of the first adaptor 210 and the outlet port 212, and then is
supplied to the
heating water pipe disposed at the returning water side.
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