CN107014066A

CN107014066A - The heat exchanger device and its application method of gas heater

Info

Publication number: CN107014066A
Application number: CN201610059547.8A
Authority: CN
Inventors: 黄国金; 吴兢先; 陈昭文
Original assignee: TAIWAN YINGHUA CO Ltd
Current assignee: TAIWAN YINGHUA CO Ltd; Taiwan Sakura Corp
Priority date: 2016-01-28
Filing date: 2016-01-28
Publication date: 2017-08-04

Abstract

The heat exchanger device and its application method of a kind of gas heater, the heat exchanger device, which has, is respectively provided with multiple perforation on multiple fins and a water pipe, each fin, water pipe is arranged in the perforation of these fins.First perforation and the second perforation are disposed adjacent the first half in fin, and the 3rd perforation, the 4th perforation and the 5th perforation are disposed adjacent in the lower half of fin.Firstth, there is a first fluid diameter De1, the region has the first area A1 and the first girth P1 between the central point line of the the 3rd and the 4th perforation；Secondth, there is a second fluid diameter De2 between the central point line of the the 4th and the 5th perforation, the region has second area A2 and the second girth P2；First, second and the 4th perforation central point line between have one the 3rd fluid diameter De3, the region have the 3rd area A3 and the 3rd girth P3；Wherein, De1=4 × (A1/P1), De2=4 × (A2/P2), De3=4 × (A3/P3).Therefore, it is possible to decrease condensation situation occurs to make gas heater reach the preferable thermal efficiency simultaneously.

Description

The heat exchanger device and its application method of gas heater

Technical field

The invention reside in the heat exchanger device and its application method for providing a kind of gas heater, especially Refer to that one kind can reduce the generation of condensation situation, and reach the heat exchange of the gas heater of the preferable thermal efficiency Device device and its application method.

Background technology

Conventional water heaters be it is general at present live indispensable device, the energy just used at home and Speech, is broadly divided into gas heater, electric heater and solar water heater etc., wherein gas and hot water Device is widely used by the public.

Conventional gas water heater is provided with blower fan, burner and heat exchanger in internal body, and the heat is handed over Parallel operation is connected with cold water pipeline and hot water line, and cold water pipeline and hot water line may make up a water passage, One end of the cold water pipeline has cold water inlet, may connect to appropriate water source, is intended to heat for inputting Cold water.One end of the hot water line has hot water outlet, can be inputted by cold water inlet and cold water pipeline The cold water to be heated, makes cold water be delivered to heat exchanger, and cold water enters heat exchanger and carries out heat exchange, Then export hot water to use by hot water line and hot water outlet.

Therefore, conventional heat exchanger easily has condensation situation when in use, so that corrosion or damage Element inside gas heater.Furthermore, such as to improve condensation situation, it is necessary to reduce the thermal efficiency, and Conventional heat exchanger endothermic effect is not good, and can not effectively lift the thermal efficiency of gas heater.

In summary, the present inventor can improve thoughts on drawbacks described above, then concentrate on studies and coordinate The application of the principles of science, proposes the present invention that is a kind of reasonable in design and being effectively improved drawbacks described above finally.

The content of the invention

The technical problems to be solved by the invention, are the heat exchanger dress for providing a kind of gas heater Put and its application method, it is possible to decrease condensation situation occurs, while making gas heater reach preferable heat Efficiency.

In order to solve above-mentioned technical problem, the present invention provides a kind of heat exchanger dress of gas heater Put, the heat exchanger device is arranged in gas heater, the heat exchanger device has multiple intervals Multiple perforation are respectively provided with the fin of setting and the water pipe being arranged in these fins, each fin, The first half and lower half of these perforation distributions in these fins, the water pipe are arranged in wearing for these fins Kong Zhong；Five perforation defined on each fin are a punch unit, and the punch unit includes one first Perforation, one second perforation, one the 3rd perforation, one the 4th perforation and one the 5th perforation, first perforation And second perforation is disposed adjacently the first half in the fin, the 3rd perforation, the 4th perforation and 5th perforation is disposed adjacently in the fin lower half, and first perforation is located at the 3rd perforation and should 4th perforation in the middle of top at, this second perforation be located at the 4th perforation and the 5th perforation in the middle of At top；Wherein, between the central point line of first perforation, the 3rd perforation and the 4th perforation With a first fluid diameter, a diameter of De1 of the first fluid is defined, the first perforation, the 3rd The central point line of perforation and the 4th perforation is surrounded by a first area, and the area of the first area is First area, the girths of Zhou Changwei first of the first area define first area for A1, and this One week a length of P1；Between the central point line of second perforation, the 4th perforation and the 5th perforation With a second fluid diameter, a diameter of De2 of the second fluid is defined, the second perforation, the 4th The central point line of perforation and the 5th perforation is surrounded by a second area, and the area of the second area is Second area, the Zhou Changwei second weeks of the second area are long, define the second area for A2, and this Two weeks a length of P2；And the central point line of first perforation, second perforation and the 4th perforation Between there is one the 3rd fluid diameter, define the 3rd fluid diameter for De3, first perforation, should The central point line of second perforation and the 4th perforation is surrounded by one the 3rd region, the face in the 3rd region Product is the 3rd area, and the girths of Zhou Changwei the 3rd in the 3rd region define the 3rd area for A3, 3rd week a length of P3；Meet following relationship condition：De1=4 × (A1/P1), De2=4 × (A2/P2), De3=4 × (A3/P3).

In order to solve the above-mentioned technical problem, the present invention also provides a kind of heat exchanger dress of gas heater The application method put, including step：There is provided one has the gas heater of described heat exchanger device, The gas heater also has a blower fan and a burner；And start the gas heater, make the combustion Burner is ignited, the burner produce high temperature burning gases, the burning gases by the first area, The second area and the 3rd region, make these fins of the contacts combustion gases heat exchanger device And water pipe so that the water flowed through in the water pipe of the heat exchanger device is heated.

The present invention at least has the advantages that following：

Because with the particular design according to above-mentioned heat exchanger device, condensation situation hair can be reduced It is raw, while making gas heater reach the preferable thermal efficiency.The present invention heat exchanger device is divided into, Temperature rise ratio is up to 1 in lower region, upper and lower region water pipe：2~1：4, to improve in upper drainpipe pipe Water temperature, reaches that reduction condensation situation occurs.The present invention can make gas heater reach the preferable thermal efficiency, And then the time of heating can be reduced, it is to avoid cause the waste of gas energy.

To enable the feature and technology contents that are further understood that the present invention, refer to below in connection with this hair Bright detailed description and accompanying drawing, but appended accompanying drawing is only provided and used with reference to explanation, not for this Invention is any limitation as.

Brief description of the drawings

Fig. 1 is the floor map of gas heater of the present invention.

Fig. 2 is the stereogram of the fin of present heat exchanger device.

Fig. 3 is the front view of the fin of present heat exchanger device.

Fig. 4 is the schematic diagram of the punch unit of present heat exchanger device.

Fig. 5 is the schematic diagram of vortex generator of the present invention.

Fig. 6 is the schematic diagram of another vortex generator of the invention.

Fig. 7 is the flow chart of the application method of present heat exchanger device.

Reference number explanation

1 body

2 blower fans

3 burners

4 heat exchanger devices

41 fins

411 perforation

412 convex portions

413 air intakes

414 gas outlets

415 vortex generators

416 vortex generators

417 vortex generators

42 water pipes

5 cold water pipelines

51 cold water inlets

6 hot water lines

61 hot water outlets

7 water quantity detectors

8 control units

H punch units

H1 first perforates

H2 second perforates

H3 the 3rd perforates

H4 the 4th perforates

H5 the 5th perforates

B1 first areas

B2 second areas

The regions of B3 the 3rd

De1 first fluid diameters

De2 second fluid diameters

The fluid diameters of De3 the 3rd

Pt1, Pt2, Pt3 spacing

Do diameters

Fp spacing

TL spacing

RL spacing

TW length

RW length

TH height

RH height

φ angles

Ψ angles

Embodiment

First embodiment

Referring to Fig. 1, the present invention provides a kind of heat exchanger device of gas heater, combustion gas heat Hydrophone includes a body 1, a blower fan 2, the heat exchanger device 4 of a burner (fire row) 3 and one. The body 1 is a hollow housing, and blower fan 2, burner 3 and heat exchanger device 4 are arranged at body Inside 1, the position that blower fan 2, burner 3 and heat exchanger device 4 are set is not intended to limit, can be because In requisition for and changed.In the present embodiment, blower fan 2, burner 3 and heat exchanger device 4 From bottom to top being arranged inside body 1 sequentially, and burner 3 is located at blower fan 2 and filled with heat exchanger Put between 4.After burner 3 is ignited, burner 3 can produce the burning gases of high temperature, burning Gas, which is pushed upwardly, to be sent, contacts combustion gases heat exchanger device 4, thus carries out the operation of heat exchange, High temperature can be heated to from normal temperature by passing through the water in heat exchanger device 4, then row discharge hot water makes With.

The heat exchanger device 4 is connected with a cold water pipeline 5 and a hot water line 6, cold water pipeline 5 And hot water line 6 constitutes a water passage, heat exchanger device 4 is connected to cold water pipeline 5 and hot-water line Between road 6.One end of the cold water pipeline 5 has a cold water inlet 51, may connect to appropriate water source, A water quantity detector 7 has been may also set up for inputting on the cold water to be heated, the cold water pipeline 5, has been used To detect amount of inlet water.One end of the hot water line 6 has a hot water outlet 61.The gas heater A control unit 8 can be further comprised, it is single that blower fan 2 and the grade device of burner 3 are electrically connected at control Member 8, to control combustion position to produce hot water using the control unit 8.

Please refer to Fig. 1 to Fig. 3, the heat exchanger device 4 has multiple spaced fins 41 and a water pipe 42 of these fins 41 is arranged in, fin 41 and water pipe 42 are with High heat conduction material (such as copper) is made, and the one end of water pipe 42 is connected to cold water pipeline 5, and the other end is connected to hot water line 6, water pipe 42 is connected between cold water pipeline 5 and hot water line 6.Can by cold water inlet 51 and Cold water pipeline 5 inputs the cold water to be heated, and cold water is delivered to heat exchanger device 4, and cold water enters Heat exchanger device 4 carries out heat exchange, then again by hot water line 6 and the heat outputting of hot water outlet 61 Water, so that user uses.

Referring again to Fig. 2 and Fig. 3, the heat exchanger device 4 can be breach formula fin design, this Multiple perforation 411 are respectively provided with the generally rectangular shaped lamellar body of a little fins 41, fin 41, these perforation 411 The first half and the lower half Liang Ge regions of fin 41 can be distributed in, perforation 411 sets quantity not Limitation, e.g. five or seven etc..The water pipe 42 is arranged in the perforation 411 of these fins 41, Also solderable connection between water pipe 42 and perforation 411.These fins 41 can be by the heat energy of burning gases Absorb, fin 41 is produced high temperature and hyperpyrexia, to carry out the work of heat exchange with the water in water pipe 42 With making water pipe 42 to discharge hot water and use.

Punching is formed with multiple convex portions 412 respectively on these fins 41, and these convex portions 412 can be protruded In the one side of fin 41, make convex portion 412 that there is appropriate height, form it into unidirectional breach formula convex Portion.These convex portions 412 can also protrude from the two sides of fin 41, form it into two-way breach formula convex portion. In the present embodiment, these convex portions 412 are arranged to the first half and the middle of fin 41, but simultaneously Do not limit, convex portion 412 may also set up in the lower half of fin 41, or on whole fin 41 it is appropriate Position.

These convex portions 412 can be rectangular, trapezoidal etc., and in the present embodiment, these convex portions 412 are most Trapezoidal, the neighbouring perforation 411 in trapezoidal convex portion 412 coordinates the design of perforation 411 trapezoidal, with Increase its area.An air intake is respectively formed between the lower edge and upper limb and fin 41 of convex portion 412 413 and a gas outlet 414, convex portion 412 is to be connected with both sides with fin 41, the side of convex portion 412 Or both sides are in angularly disposed.Because the construction of convex portion 412 is identical with conventional art, and the present invention is not limited The construction of convex portion 412 processed, therefore be not repeated here.

Multiple vortex generators 415,416 and 417 are respectively equipped with these fins 41, it can distinguish Protrude from the one side or another side of fin 41.The construction of these vortex generators 415,416 and 417 It is not intended to limit, such as can be rectangular, trapezoidal or drops.In the present embodiment, these vortex productions Raw device 415 is rectangular, and these vortex generators 415 are located at these of the first half of fin 41 and worn At top between hole 411, that is, these vortex generators 415 can be in along horizontal direction extension Strip, and these vortex generators 415 are located at these perforation 411 of the first half of these fins 41 At middle top.These vortex generators 416 are trapezoidal, and are relatively arranged on these perforation two-by-two At 411 top, that is, these vortex generators 416 can obliquely be oppositely arranged these two-by-two At the top both sides of perforation 411.These vortex generators 417 are in drops, and these vortex are produced Device 417 is located at the middle of fin 41.These vortex generators 415,416 and 417 can be by gas Concentrate, nullified area is reduced, and these vortex generators 415,416 and 417 can also produce whirlpool Stream, makes the thermal efficiency of gas heater effectively be lifted.

Referring again to Fig. 1 to Fig. 5, a diameter of do of these perforation 411 is further defined, per adjacent Two spacing of fin 41 be Fp, the trapezoidal vortex generator 416 at the top of perforation 411 For right-angled trapezium, the length of the bottom of the vortex generator 416 is TW, is highly TH, bottom Angle with waist (waist of hypotenuse) is φ, the bottom of the vortex generator 416 and the circle of perforation 411 The spacing of the heart is TL, by 411 center of circle of perforation and vertical with the bottom of vortex generator 416 Dummy line and horizontal angle are Ψ, meet following relationship condition：

TL=do+2.2~do+4

TH=0.7Fp~0.82Fp

Ψ=25 °~47 °

φ=24 °~48 °

TW=0.45do~0.66do

Wherein, TL, TH, Fp, TW and do unit are mm.

Referring again to Fig. 1 to Fig. 6, a diameter of do of these perforation 411 is further defined, per adjacent The spacing of two fin 41 be Fp, positioned at fin 41 the first half these perforation 411 between top The rectangular vortex generator 415 in place, its length is RW, is highly RH, the vortex generator 416 bottom and the spacing of the dummy line in the center of circle of these perforation 411 of the first half by fin 41 For RL, following relationship condition is met：

RL=0.68do~0.8do

RW=0.63do~0.75do

RH=0.7Fp~0.84Fp

Wherein, RL, RW, RH, Fp and do unit are mm.

Referring again to Fig. 4, it is a punch unit H to define every five perforation 411 on each fin 41, Punch unit H includes one first perforation h1, one second perforation h2, one the 3rd perforation h3, one the Four perforation h4 and one the 5th perforation 45, the first perforation h1 and the second perforation h2 are disposed adjacent in fin 41 first half, the 3rd perforation h3, the 4th perforation h4 and the 5th perforation h5 are disposed adjacent in fin 41 lower half, the first perforation h1 is located at the top in the middle of the 3rd perforation h3 and the 4th perforation h4, Second perforation h2 is located at the top in the middle of the 4th perforation h4 and the 5th perforation h5.First perforation h1 And second perforation h2 can be located at same level height, the 3rd perforation h3, the 4th perforation h4 and the 5th wear Hole 45 can be located at same level height.

Wherein, between the first perforation h1, the 3rd perforation h3 and the 4th perforation h4 central point line With a first fluid diameter, a diameter of De1 of the first fluid is defined.First perforation h1, the 3rd wear The first area B1 that the perforation of hole h3 and the 4th h4 central point line is surrounded by, the first area B1 area is the first area, and the girths of Zhou Changwei first define first area for A1, this first Zhou Changwei P1.

Have one between second perforation h2, the 4th perforation h4 and the central point line of the 5th perforation 45 Second fluid diameter, defines the second fluid a diameter of De2, the second perforation h2, the 4th perforation h4 And the 5th perforation 45 the second area B2 that is surrounded by of central point line, second area B2's Area is second area, and Zhou Changwei second weeks are long, defines the second area for A2, second girth For P2.First area B1 and second area B2 can be identical or symmetrical.

Have one between first perforation h1, the second perforation h2 and the 4th perforation h4 central point line 3rd fluid diameter, defines the 3rd fluid diameter for De3, the first perforation h1, the second perforation h2 And the 4th perforation h4 one the 3rd region B3 that is surrounded by of central point line, the 3rd region B3's Area is the 3rd area, and the girths of Zhou Changwei the 3rd define the 3rd area for A3, the 3rd girth For P3.

According to Ke Enfa (Kern Method)

Nu=hDe/k

De=4 flow areas/wetting circumference

The present invention meets following relationship condition：

De (fluid diameter)=4 × (A/P), wherein A are the area in each region, and P is each region Girth.

Specifically, the present invention meets following relationship condition：

De1=4 × (A1/P1)

De2=4 × (A2/P2)

De3=4 × (A3/P3)

In addition, preferred scope of design, meets following relationship condition：

De3/ (De1+De2)=0.48~0.43

De2/ (De1+De2)=0.52~0.44

Furthermore it is possible to define the spacing of the 3rd perforation h3 central point and the 4th perforation h4 central point For Pt1, the spacing of the 4th perforation h4 central point and the 5th perforation h5 central point is Pt2, first The spacing of perforation h1 central point and the second perforation h2 central point is Pt3, meets following relationship Condition：

Pt1 ＞ Pt2 ＞ Pt3

Second embodiment

Referring to Fig. 7, the present invention separately provides a kind of use of the heat exchanger device 4 of gas heater Method, including step are as follows：

There is provided a gas heater (also referring to Fig. 1 to Fig. 6), the gas heater first With described heat exchanger device 4；Due to the gas heater and the heat exchanger device 4 with it is upper State embodiment identical, no longer repeated；

Then, start the gas heater, be ignited the burner 3, the burner 3 produces height Temperature burning gases, the burning gases, which are pushed upwardly, to be sent, the burning gases by first area B1, Second area B2 and the 3rd region B3, makes these of the contacts combustion gases heat exchanger device 4 Fin 41 and water pipe 42, thus carry out heat exchange operation, and the contacts combustion gases these vortex Vortex is concentrated and produced to burning gases so that flow through the heat exchange by generator 415,416 and 417 Water in the water pipe 42 of device device 4 is heated, for example, high temperature is heated to from normal temperature, to discharge Hot water is used.

Because, according to the particular design of above-mentioned heat exchanger device, condensation situation hair can be reduced It is raw, while making gas heater reach the preferable thermal efficiency.The present invention heat exchanger device is divided into, Temperature rise ratio is up to 1 in lower region, upper and lower region water pipe：2~1：4, concentrate on down heating Region.The present invention can improve water temperature in drainpipe pipe, reach that reduction condensation situation occurs.This hair It is bright gas heater is reached the preferable thermal efficiency, and then the time of heating can be reduced, it is to avoid cause The waste of gas energy.The present invention after tested, arranges temperature rise ratio 1 up and down：2.1, the thermal efficiency is up to 83.02%； Temperature rise ratio 1 is arranged up and down：3, the thermal efficiency is up to 83.6%, and condensation is less susceptible to hair with producing carbon distribution situation It is raw.

The preferred embodiments of the present invention are the foregoing is only, the patent protection of the limitation present invention is not intended to Scope, therefore the equivalence changes that every application description of the invention and accompanying drawing content are made, are similarly all wrapped It is contained in the scope of the present invention, declares hereby.

Claims

1. a kind of heat exchanger device of gas heater, it is characterised in that the heat exchanger device It is arranged in the gas heater, the heat exchanger device has multiple spaced It is each on fin and the water pipe being arranged in the multiple spaced fin, each fin Provided with multiple perforation, the multiple perforation distributions are upper in the multiple spaced fin Half portion and lower half, the water pipe are arranged in the perforation of the multiple spaced fin；

Five perforation defined on each fin are a punch unit, and the punch unit includes One first perforation, one second perforation, one the 3rd perforation, one the 4th perforation and one the 5th perforation, First perforation and second perforation are disposed adjacently in the first half of the fin, institute The 3rd perforation, the 4th perforation and the 5th perforation is stated to be disposed adjacently in the fin Lower half, it is described first perforation be located at the described 3rd perforation and it is described 4th perforation in the middle of At top, second perforation is upper in the middle of the described 4th perforation and the 5th perforation At side；

Wherein, the central point of first perforation, the 3rd perforation and the 4th perforation There is a first fluid diameter between line, a diameter of De1 of first fluid, institute is defined The central point line for stating the first perforation, the 3rd perforation and the 4th perforation is surrounded by one First area, the area of the first area is the first area, the girth of the first area For the first girth, it is A1, first week a length of P1 to define first area；

It is described second perforation, it is described 4th perforation and it is described 5th perforation central point line it Between there is a second fluid diameter, define a diameter of De2 of second fluid, described second The central point line of perforation, the 4th perforation and the 5th perforation is surrounded by one second area Domain, the area of the second area is second area, the Zhou Changwei second of the second area Girth, it is A2, a length of P2 of second week to define the second area；And

It is described first perforation, it is described second perforation and it is described 4th perforation central point line it Between there is one the 3rd fluid diameter, it is De3, described first to define the 3rd fluid diameter The central point line of perforation, second perforation and the 4th perforation is surrounded by one the 3rd area Domain, the area in the 3rd region is the 3rd area, the Zhou Changwei the 3rd in the 3rd region Girth, it is A3, the 3rd week a length of P3 to define the 3rd area；Meet following pass It is formula condition：

De1=4 × (A1/P1), De2=4 × (A2/P2), De3=4 × (A3/P3).

2. the heat exchanger device of gas heater according to claim 1, wherein, it is described many Multiple vortex generators are respectively equipped with individual spaced fin, the multiple vortex is produced Device is rectangular, and the multiple vortex generator is located at the upper of the multiple spaced fin At top between the multiple perforation of half portion.

3. the heat exchanger device of gas heater according to claim 2, wherein, it is described many Individual vortex generator is in strip along horizontal direction extension, defines the straight of the multiple perforation Footpath is do, and the spacing of two adjacent fins is Fp, and the length of the vortex generator is RW, the height of the vortex generator is RH, and the bottom of the vortex generator is with passing through The spacing of the dummy line in the center of circle of the multiple perforation of the first half of the fin is RL, full Sufficient following relationship condition：RL=0.68do~0.8do, RW=0.63do~0.75do, RH=0.7 Fp~0.84Fp.

4. the heat exchanger device of gas heater according to claim 1, wherein, it is described many Multiple vortex generators are respectively equipped with individual spaced fin, the multiple vortex is produced Device is trapezoidal, and is oppositely disposed two-by-two at the top of the multiple perforation, and definition is described A diameter of do of multiple perforation, the spacing of two adjacent fins is Fp, and the vortex is produced The length of the bottom of device is TW, and the height of the vortex generator is TH, the vortex production It is φ to give birth to the bottom of device and the angle of waist, bottom and the perforation of the vortex generator The spacing in the center of circle is TL, by the center of circle of the perforation and with the bottom of the vortex generator Vertical dummy line and horizontal angle are Ψ, meet following relationship condition： TL=do+2.2~do+4, TH=0.7Fp~0.82Fp, Ψ=25 °~47 °, φ=24 °~48 °, TW=0.45do~0.66do, above-mentioned TL, TH, Fp, TW and do unit are mm.

5. the heat exchanger device of gas heater according to claim 4, wherein, it is described many Individual vortex generator is obliquely oppositely disposed two at the top of the multiple perforation two-by-two Side.

6. the heat exchanger device of gas heater according to claim 1, wherein, also meet Following relationship condition：De3/ (De1+De2)=0.48~0.43.

7. the heat exchanger device of gas heater according to claim 1, wherein, also meet Following relationship condition：De2/ (De1+De2)=0.52~0.44.

8. the heat exchanger device of gas heater according to claim 1, wherein, define institute The spacing of the central point and the central point of the described 4th perforation of stating the 3rd perforation is Pt1, described the The spacing of the central point of four perforation and the central point of the described 5th perforation is Pt2, and described first wears The spacing of the central point in hole and biperforate central point is Pt3, meets following relationship Condition：Pt1 ＞ Pt2 ＞ Pt3.

9. the heat exchanger device of gas heater according to claim 1, wherein, described One perforation and second perforation are located at same level height, the 3rd perforation, described the Four perforation and the 5th perforation are located at same level height.

10. a kind of application method of the heat exchanger device of gas heater, it is characterised in that described to make Comprised the following steps with method：

One is provided with the heat exchanger device according to any one of claim 1 to 9 Gas heater, the gas heater also has a blower fan and a burner；And

Start the gas heater, be ignited the burner, the burner is produced The burning gases of high temperature, the burning gases pass through the first area, the second area And the 3rd region, make the described many of heat exchanger device described in the contacts combustion gases Individual spaced fin and the water pipe so that flow through the water pipe of the heat exchanger device Interior water is heated.