WO2008111722A1

WO2008111722A1 - Electric boiler

Info

Publication number: WO2008111722A1
Application number: PCT/KR2007/006534
Authority: WO
Inventors: Hee-Tae Lee; Hyeog-Won Kim
Original assignee: Hee-Tae Lee; Hyeog-Won Kim
Priority date: 2007-03-14
Filing date: 2007-12-14
Publication date: 2008-09-18

Abstract

An electric boiler is provided. A water heater (60) installed inside a reservoir tub (50) separates a portion of low temperature water stored in the reservoir tub (50) through an inlet (52) and rapidly heats the water to high temperature. The rapidly heated high temperature water is rapidly supplied to the upper portion of the reservoir (50) through a hot water supply pipe (70) and drained to a heating pipe through an outlet (54) of the reservoir tub (50). Therefore, after performing a heating operation through the heating pipe, the high temperature water flows back to the inlet (52) of the reservoir tub (50). Since the low temperature water is drained to the outlet (54) through the hot water supply pipe (70) after heated by the water heater (60), the heating operation can be immediately performed simultaneously with an operation, and the low temperature hot water of the reservoir tub (50) can be heated and heat can be stored in a short time. Therefore, heating efficiency can be maximized at low costs.

Description

ELECTRIC BOILER

Technical Field

[1] The present invention relates to an electric boiler heating reservoir water using electricity, and more particularly, to an electric boiler that can not only instantly heat and use a portion of reservoir water but also store heat using the portion of the heated water. Background Art

[2] Generally, an electric boiler is used in households, factories, or agricultural and stockbreeding farmhouses. Particularly, an electric boiler used in the factories or agricultural and stockbreeding farmhouses is classified into an electric boiler for industrial use and thus is manufactured to have a large capacity, and heats reservoir water generally using midnight electricity whose price is cheap.

[3] Referring to Fig. 1, the general electric boiler heats low temperature water stored in a reservoir tub 2 through a water pipe 5 to high temperature using an electric heater 3 installed in the lower portion of the reservoir tub 2 to drain the water to a drainpipe 4. At this point, the low temperature water stored in the reservoir tub 2 is gradually heated by the electric heater 3, and heated entirely while circulating through the reservoir tub 2 due to a temperature difference. That is, the water stored in the reservoir tub 2 is entirely heated as a time elapses.

[4] Here, the water pipe 5 and the drainpipe 4 are connected to a circulation type heating pipe (not shown). Therefore, the heating pipe heats a floor using the high temperature water supplied to the drainpipe 4, or supplies warm air to a plastic greenhouse of a factory or farmhouse through a blower fan (not shown).

[5] A heating pump is installed to the heating pipe (not shown). Both ends of the heating pipe are connected to the drainpipe 4 and the water pipe 5, respectively, to form a closed loop. Therefore, the heating pipe receives and circulates high temperature hot water through the drainpipe 4, and then supplies the hot water cooled while circulating back to the water pipe 5 upon operation of the heating pump. That is, the heating pipe supplies again the hot water that has been used for a heating operation to the water pipe 5 so that the water that has changed into low temperature water while it is used for the heating operation is heated again by the electric heater 3 and re- circulates through the drainpipe 4.

[6] At this point, high temperature water resupplied to the water pipe 5 through the heating pipe is changed into low temperature water by heat exchange during a heating operation, and resupplied. That is, low temperature water is resupplied to the water pipe 5. Therefore, the electric heater 3 reheats low temperature water that has been resupplied to the water pipe 5 and supplies the heated water to the drainpipe 4 of the reservoir tub 2.

[7] However, since high temperature hot water is drained only when low temperature water stored in the reservoir tub 2 is all heated by the electric heater 3 according to the general electric boiler as illustrated, the high temperature hot water cannot be immediately used at the right moment, and it takes too excessive time to heat the low temperature water.

[8] Particularly, in the case where the general boiler is manufactured in a large capacity, low temperature water of a large-scale reservoir tub 2 should be heated for about one hour to heat the low temperature water to a temperature suitable for a heating operation. Therefore, the large-capacity general electric boiler cannot instantly use high temperature water, cannot continuously use the high temperature water on time, and it is not until a heating time of about one hour that a substantial heating operation is performed.

[9] Also, the electric boiler manufactured in the large capacity has a limitation of having to keep operating the electric heater 3 without stoppage because hot water of the reservoir tub 2 is drained to the drainpipe 4 in the upper portion U of the reservoir tub 2 while the electric heater 3 heats low temperature water resupplied to the water pipe 5 in the lower portion L of the reservoir tub 2 after a heating operation is performed.

[10] Of course, in case of adding the capacity of the electric heater 3, low temperature water of the reservoir tub 2 can be heated more quickly. That is, in case of increasing the number of electric heaters 3, the low temperature water can be heated more quickly. However, in case of adding the capacity of the electric heater 3, the manufacturing costs and sales unit price of the electric boiler increase due to the additional cost of the electric heater 3.

[11] Therefore, the most of general electric boilers manufactured in a large capacity heat the low temperature water of the reservoir tub 2 using cheap midnight electricity without adding the electric heaters 3. However, since an excessive much heating time is consumed even when the general large-capacity electric boiler uses midnight electricity, an excessive electricity bill is charged.

[12] Meanwhile, the general large-capacity electric boiler performs a heating operation all the night through. Also, when the heating operation is suspended, the low temperature water of the reservoir tub 2 is heated to high temperature to store heat so that the hot water heated by the reservoir tub 2 can be used in the daytime. That is, the electric boiler not only performs the heating operation all the night through using midnight electricity, but also heats the low temperature water of the reservoir tub 2 to high temperature to preliminary store heat using the lower temperature water. However, according to the general large-capacity electric boiler, excessive electricity bill is charged due to an excessive long heating time as described above.

[13] Meanwhile, according to the above-described general electric boiler, it is substantially impossible to heat the low temperature water of the reservoir tub 2 to about 88⁰C or more because hot water heated by the reservoir tub 2 is continuously drained through the drainpipe 4 and the water that has been cooled is continuously supplied through the water pipe 5. Of course, in the case where the hot water heated by the reservoir tub 2 is not drained through the drainpipe 4, the low temperature water can be heated to about 88⁰C or more. In the general electric boiler, the water is not heated to about 88⁰C or more because the hot water is continuously drained through the drainpipe 4. Therefore, since the general electric boiler performs a heating operation using hot water heated to about 88⁰C or below, a high heating efficiency cannot be expected. That is, the general electric boiler has low heating efficiency.

[14] Also, according to the electric boiler, since the hot water heated to about 88⁰C or below performs a heating operation through a heating pipe (not shown), and then changes into low temperature water of about 6O⁰C or below and resupplied to the water pipe 5 of the reservoir tub 2, the lower portion L of the reservoir tub 2 is rapidly cooled. That is, the upper portion U of the reservoir tub 2 is heated to about 88⁰C but the lower portion L is cooled to about 6O⁰C. Therefore, even when the electric heater 3 of the general electric boiler continuously heats low temperature water supplied to the lower portion L of the reservoir tub 2, the inner temperature of the reservoir tub 2 gradually lowers. Of course, the reservoir tub 2 drains hot water of about 84⁰C through the drainpipe 4 as the inner temperature lowers. That is, the inner temperature of the reservoir tub 2 lowers up to about 84⁰C. Since the inner temperature of the reservoir tub 2 lowers to about 84⁰C, the heating efficiency of the general electric boiler drops down even more. Disclosure of Invention Technical Problem

[15] Embodiments provide an electric boiler having an instant hot water type mechanism that instantly and rapidly heats a portion of low temperature water stored in a reservoir tub to automatically provide the heated water to the upper portion of the reservoir tub.

[16] Embodiments also provide an electric boiler that can separate a portion of low temperature water into one place to heat the portion of the low temperature water in a simultaneous and frequent occurrence manner, and can divide the separated low temperature water to heat the same in a simultaneous and frequent occurrence manner.

[17] Embodiments also provide an electric boiler having a mechanism that collects and diffuses separated and rapidly heated hot water at the upper portion of a reservoir tub.

[18] Embodiments also provide an electric boiler having a mechanism that forcibly supplies hot water existing in the upper portion of a reservoir tub to the lower portion of the reservoir tub to circulate the water.

[19] Embodiments also provide an electric boiler that can rapidly supply high temperature water instantly and rapidly heated by a water heater to a heating pipe while securing flux corresponding to a pumping pressure of a heating pump when the heating pump connected to the heating pipe operates to heat an indoor space.

[20] Embodiments also provide an electric boiler having a member integrally formed with a water heater, the member having a structure that allows low temperature water to be supplied to the water heater and prevents high temperature water heated by the water heater from flowing backward.

[21] Embodiments also provide an electric boiler that can supply hot water for a bathroom use separately from hot water for a heating operation using hot air of a water heater.

Technical Solution

[22] In one embodiment, an electric boiler performing a heating operation while changing low temperature water flowing from an outside into high temperature water using electricity, and draining the high temperature water using a pumping pressure of a heating pump, the electric boiler including: a reservoir tub whose four sides are closed, storing low temperature water flowing into an inlet provided in one side, and heating the stored low temperature water to high temperature to drain the heated water through an outlet provided in an upper portion; a water heater separating a portion of the low temperature water stored in the reservoir tub and rapidly heating the separated low temperature water to high temperature using electricity supplied from an outside; and a hot water supply pipe guiding the high temperature water rapidly heated by the water heater to an upper portion of the reservoir tub to supply the high temperature water to the upper portion of the reservoir tub and the outlet of the reservoir tub. Brief Description of the Drawings

[23] Fig. 1 is a vertical cross-sectional view of a general electric boiler.

[24] Fig. 2 is a vertical cross-sectional view of an electric boiler according to a first embodiment of the present invention.

[25] Fig. 3 is a vertical cross-sectional view of an electric boiler according to a second embodiment of the present invention.

[26] Fig. 4 is a table illustrating experimental results of an electric boiler according to an embodiment of the present invention.

[27] Fig. 5 is a vertical cross-sectional view of an electric boiler according to a third embodiment of the present invention.

[28] Fig. 6 is a vertical cross-sectional view of an electric boiler according to a fourth embodiment of the present invention.

[29] Fig. 7 is a vertical cross-sectional view of a backward flow suppression member installed to the water heater of Figs. 5 and 6. Best Mode for Carrying Out the Invention

[30] Embodiments of the present invention will now be described below with reference to the accompanying drawings. Fig. 2 is a vertical cross-sectional view of an electric boiler according to a first embodiment of the present invention.

[31] Referring to Fig. 2, the electric boiler includes: a reservoir tub 50 filled with and storing low temperature water; a water heater 60 rapidly heating a portion of the low temperature water stored in the reservoir tub 50 to high temperature to supply high temperature water; and a hot water supply pipe 70 supplying the high temperature water heated by the water heater 60 to an upper portion of the reservoir tub 50. The elements of the electric boiler according to the embodiment of the present invention will be described in detail below.

[32] The reservoir tub 50 is formed in a cylindrical shape or a polygonal cylindrical shape whose four sides are closed. Referring to Fig. 2, hole shaped inlet 52 and outlet 54 are integrally formed in the lower portion L and the upper portion U of the reservoir tub 50, respectively. At this point, pipes are fit in the inlet 52 and the outlet 54, respectively, as illustrated. Closed loop type circulation heating pipes (not shown) are connected to the inlet 52 and the outlet 54 of the reservoir tub 50, respectively. Therefore, the reservoir tub 50 drains high temperature water heated by the water heater 60 to the outside through the outlet 54 connected to the heating pipe, and receives low temperature water cooled while it is used for a heating operation through the inlet 52 connected to the heating pipe.

[33] Here, the above-described heating pipe is connected to a heating pump (not shown).

Therefore, as the outlet 54 is connected to the heating pipe, a pumping pressure of the heating pump operates. Of course, the outlet 54 drains high temperature water due to the pumping pressure of the heating pump. That is, the high temperature water is drained by the pumping pressure of the heating pump.

[34] Next, the water heater 60 is mounted inside the reservoir tub 50 as illustrated, separates a portion of low temperature water stored in the reservoir tub 50, and rapidly heats the portion of the low temperature water to high temperature using electricity supplied from the outside. That is, the water heater 60 heats a portion of the low temperature water using electricity. The water heater 60 can be installed in the middle or upper portion U of the reservoir tub 50. However, the water heater 60 may be installed in the lower portion L of the reservoir tub 50 as illustrated so that low temperature water is heated and rises due to a temperature difference to naturally flow through convection. That is, the water heater 60 may be installed in the lower portion L of the reservoir tub 50 with consideration of a heat exchange characteristic.

[35] The water heater 60, for example, can include a closed type separation chamber 62 integrally mounted in the lower portion L of the reservoir tub 50, and electric heaters 64 mounted inside the separation chamber 62 as illustrated.

[36] Here, a through hole 62a is formed in one side of the above-described separation chamber 62 as illustrated. Also, the hot water supply pipe 70 is integrally connected on the other side of the separation chamber 62. At this point, the through hole 62a is formed in the lower portion of the separation chamber 62, and the hot water supply pipe 70 is connected to the upper portion of the separation chamber 70. Therefore, the separation chamber 62 receives and separates a portion of low temperature water stored in the lower portion L of the reservoir tub 50 through the through hole 62a. Also, the separation chamber 62 heats the separated portion of the low temperature water using the electric heater 64 mounted therein to supply the heated water to the hot water supply pipe 70.

[37] Meanwhile, the above-described electric heater 64 is mounted inside the separation chamber 62 as illustrated to heat separated water by the separation chamber 62 while emitting heat using electricity from the outside. At this point, a portion of the low temperature water separated by the separation chamber 62 is rapidly heated because it is separated by the separation chamber 62.

[38] Here, the above-described electric heater 64 can be a single member as enlarged, or can include a plurality of members. In the case where a plurality of electric heaters 64 are provided, the plurality of electric heaters 64 may be separated from one another and arranged in parallel. Therefore, in the case where the plurality of electric heaters 64 are provided, the heaters 64 heat the water separated inside the separation chamber 62 simultaneously and respectively.

[39] In the case where the plurality of electric heaters 64 are provided, a baffle 66 can be interposed between the electric heaters 64 as illustrated. One end of the baffle 66 is fixed inside the separation chamber 62 as illustrated. The other end of the baffle 66 is separated from the inner surface of the separation chamber 62 to form a free end. Therefore, the baffle 66 controls a portion of the low temperature water separated by the separation chamber 62 so that the water can circulate through the other end on the free end. That is, the baffle 66 separates the plurality of electric heaters 64 mounted inside the separation chamber 62 while shielding the electric heaters 64 so that water circulates inside the separation chamber 62.

[40] One end of the hot water supply pipe 70 is connected to the other side of the separation chamber 62. Also, the other end of the hot water supply pipe 70 is located at the upper portion L of the reservoir tub 50 as illustrated. Therefore, the hot water supply pipe 70 guides hot water heated to high temperature inside the separation chamber 62 to the upper portion U of the reservoir tub 50. That is, the hot water supply pipe 70 supplies the hot water rapidly heated by the separation chamber 62 to the outlet 54 provided to the upper portion U of the reservoir tub 50.

[41] A plurality of water supply pipes 70 can be provided as illustrated, or a single water supply pipe 70 can be provided unlike the illustration. It is preferable that the plurality of water supply pipes 70 are provided as illustrated so that the hot water is uniformly supplied to the upper portion U of the reservoir tub 50.

[42] An operation of an electric boiler according to the first embodiment of the present invention having the above-described construction will be described below with reference to Fig. 2. At this point, description is made using an example where the plurality of electric heaters 64 are provided and separated by the baffle 66 as illustrated.

[43] Referring to the accompanying drawings, low temperature water is supplied through the inlet 52 in the electric boiler according to the first embodiment of the present invention. At this point, the reservoir tub 50 is filled with the low temperature water supplied through the inlet 52 to store the water up to the upper end. The reservoir tub 50 supplies a portion of the low temperature water stored in the lower portion L of the reservoir tub 50 to the separation chamber 62 of the water heater 60. Of course, the separation chamber 62 receives a portion of the low temperature water through the through hole 62a formed in one side of the separation chamber 62.

[44] The separation chamber 62 separates a portion of the low temperature water from the outside as illustrated. At this point, the plurality of electric heater 64 of the water heater 60 heat the portion of the low temperature water separated by the separation chamber 62 to high temperature while emitting heat using electricity supplied from the outside. Therefore, the portion of the low temperature water separated by the separation chamber 62 is entirely heated to high temperature water. Of course, the separation chamber 62 heats together low temperature water existing around its outer surface because the hot water inside the separation chamber 62 exchanges heat with the low temperature water existing around its outer surface. That is, the low temperature water surrounding the outer surface of the separation chamber 62 is somewhat heated by the high temperature hot water separated inside the separation chamber 62.

[45] The high temperature hot water separated inside the separation chamber 62 is supplied to the upper portion U of the reservoir tub 50 through the hot water supply pipe 64. The hot water supply pipe 64 supplies the high temperature hot water separated inside the separation chamber 62 to the upper portion U of the reservoir tub 50 as low temperature water that has been used for a heating operation continuously flows into the inlet 52 of the reservoir tub 50. That is, the low temperature water supplied through the inlet 52 is introduced to the separation chamber 62 by discharge pressure, and the high temperature hot water separated inside the separation chamber 62 moves along the hot water supply pipe 64 due to the pressure of the low temperature water flowing to the separation chamber 62. Of course, the high temperature hot water separated inside the separation chamber 62 move more swiftly along the hot water supply pipe 64 due to convection phenomenon caused by a temperature difference. Therefore, the hot water supply pipe 64 supplies the hot water heated by the separation chamber 62 to the upper portion U of the reservoir tub 50.

[46] Meanwhile, the outlet 54 formed in the upper portion U of the reservoir tub 50 drains high temperature hot water discharged from the hot water supply pipe 64. Therefore, the heating pipe (not shown) connected to the outlet 54 directly circulates the high temperature hot water rapidly heated by the water heater 60 to heat an indoor space.

[47] Meanwhile, the baffle 66 installed to the separation chamber 62 divides the separation chamber 62 around the electric heater 64. That is, the baffle 66 divides the separation chamber 62 into an upper portion and a lower portion. Also, baffle 66 circulates high temperature hot water heated at the lower portion of the separation chamber 62 through the other end on the free end side to the upper portion of the separation chamber 62.

[48] At this point, the electric heater 64 of the electric heaters 64 disposed in the lower portion of the separation chamber 62 primarily rapidly heats low temperature water in the lower portion of the separation chamber 62 controlled by the baffle 66. The other electric heater 64 disposed in the upper portion of the separation chamber 62 secondarily rapidly heats the high temperature hot water that has been primarily rapidly heated and introduced through the other end of the baffle 66. Therefore, the water heater 60 heats the low temperature water separated inside the separation chamber 62 to high temperature of about 97⁰C. Of course, the hot water heated to the high temperature is supplied to the outlet 54 of the reservoir tub 50 through the hot water supply pipe 70.

[49] Meanwhile, since high temperature hot water is supplied from the hot water supply pipe 70 to the upper portion U of the reservoir tub 50, and hot water cooled while it is used for a heating operation flows into the lower portion L of the reservoir tub 50 through the inlet 52, the temperature of the upper portion U is much higher than that of the lower portion L.

[50] Since the water heater 60 rapidly heats low temperature water, the electric boiler according to the first embodiment of the present invention generates high temperature hot water in an instant to heat an indoor space. Also, the plurality of electric heaters 64 heat low temperature water, respectively, and reheat the low temperature water using the baffle 66 to allow hot water heated to very high temperature to be supplied to the heating pipe (not shown).

[51] Unlike this, in the case where a heating operation is not performed, the electric heater according to the first embodiment stores heat while entirely heating the water stored in the reservoir tub 50 through the electric heaters 64. At this point, the hot water supply pipe 70 continuously supplies high temperature hot water heated by the electric heaters 64 to the upper portion U of the reservoir tub 50. Accordingly, the high temperature hot water supplied to the upper portion U of the reservoir tub 50 performs a heat change operation while moving to the lower portion of the reservoir tub 50 due to a convection phenomenon caused by a temperature difference. Also, the high temperature hot water moving to the lower portion L of the reservoir tub 50 flows back to the separation chamber 62 of the water heater 60 and is heated to high temperature, and then circulates again. Therefore, while the water stored in the reservoir tub 50 is heated to high temperature in a short time, heat is stored.

[52] Meanwhile, Fig. 3 is a vertical cross-sectional view of an electric boiler according to a second embodiment of the present invention. The electric boiler according to the second embodiment is almost the same in its construction as that of the electric boiler according to the first embodiment. Only difference is that a water intake chamber 80 is installed at the upper end of the hot water supply pipe 70 and a circulation member 90 is installed to the reservoir tub 50 as illustrated. Therefore, only the difference will be described below with reference to the accompanying drawings.

[53] As illustrated, the electric boiler according to the second embodiment includes the water intake chamber 80 installed at the upper end of the hot water supply pipe 70 as illustrated. That is, one side of the water intake chamber 80 is connected to the end on the discharge side of the hot water supply pipe 70. As illustrated, the water intake chamber 80 includes a plurality of discharge holes 80a on the other side through which hot water is drained. Therefore, the water intake chamber 80 takes in high temperature hot water discharged from the hot water supply pipe 70 to diffuse the hot water along a lengthwise direction, and simultaneously, entirely provides the diffused hot water to the upper portion U of the reservoir tub 50 through the discharge holes 80a in one side. Therefore, high temperature hot water is entirely swiftly distributed to the upper portion U of the reservoir tub 50.

[54] Here, a plurality of discharge holes 80a can be provided, or a single discharge hole

80a can be provided. It is preferable that the plurality of discharge holes 80a are provided as illustrated so that high temperature hot water taken in the water intake chamber 80 is uniformly entirely distributed in the upper portion U of the reservoir tub 50.

[55] A discharge pipe 82 enlarged in the drawing can be connected to the discharge hole

80a. That is, the discharge pipe 82 can be connected to the water intake chamber 80. Therefore, high temperature hot water diffused while it is taken in the water intake chamber 80 is supplied to the upper portion U of the reservoir tub 50 through the discharge pipe 82.

[56] Here, the discharge pipe 82 can be configured in a straight line shape unlike the illustration, or configured to be bent toward the outlet 54 as illustrated so that high temperature hot water is easily supplied to the outlet 54 of the reservoir tub 50.

[57] Meanwhile, the circulation member 90 installed to the reservoir tub 50 allows high temperature hot water stored in the upper portion of the reservoir tub 50 by the hot water supply pipe 70 to circulate to the lower portion L of the reservoir tub 50. Therefore, since the high temperature hot water is circulated by the circulation member 90, the low temperature water stored in the reservoir tub 50 is entirely heated in a short time.

[58] Here, the circulation member 90, for example, can include: a bypass pipe 92 connected from the upper portion U of the reservoir tub 50 to the lower portion L of the reservoir tub 50; and a circulation pump 94 connected to the bypass pipe 92.

[59] Both ends of the bypass pipe 92 are connected to the inlet 52 and the outlet 54 of the reservoir tub 50, respectively, as illustrated. Therefore, the bypass pipe 92 receives the high temperature hot water introduced to the upper portion U of the reservoir tub 50 through the outlet 54, and allows the hot water to flow to the lower portion L of the reservoir tub 50 through the inlet 52. At this point, the circulation pump 94 is connected to the bypass pipe 92 as illustrated to pump the high temperature hot water flowing through the bypass pipe 92 to the lower portion L of the reservoir tub 50. Therefore, the circulation member 90 allows the high temperature hot water existing in the upper portion U of the reservoir tub 50 to forcibly circulate to the lower portion L of the reservoir tub 50.

[60] Meanwhile, the electric boiler according to the second embodiment of the present invention can selectively adopt the circulation member 90 if necessary. That is, the circulation member 90 can be omitted. The circulation member 90 can be adopted to the electric boiler illustrated in Fig. 2. That is, the electric boiler illustrated in Fig. 2 can further include the circulation member 90 illustrated in Fig. 3.

[61] Meanwhile, Fig. 4 is a table illustrating experimental results of an electric boiler according to an embodiment of the present invention. Here, the illustrated comparison example uses the general electric boiler illustrated in Fig. 1 including the reservoir tub having a capacity of about 2700 liters and the two electric heaters having a caloric value of about 60 Kcal. Also, the illustrated experimental example uses the electric boiler according to the second embodiment illustrated in Fig. 3 including the reservoir tub having a capacity of about 2700 liters, the two electric heaters having a caloric value of about 60 Kcal, and the circulation pump having power of about 200 W. That is, the illustrated comparison example represents the performance of the general electric boiler, and the experimental example represents the performance of the electric boiler according to the second embodiment of the present invention.

[62] The comparison example and the experimental example have installed temperature sensors in the upper portion U and the lower portion L of the reservoir tub, respectively, and then measured the performances after low temperature water stored in the reservoir tub is heated to about 9O⁰C. At this point, in the electric boiler according to the comparison example, the low temperature water in the reservoir tub has been heated to about 9O⁰C after about one hour has elapsed. On the other hand, the electric boiler according to the experimental example has been heated to about 9O⁰C after about forty five minutes have elapsed. That is, the electric boiler according to the experimental example has showed about 30% higher heating efficiency than that of the electric boiler according to the comparison example. The performances of the electric boilers according to the comparison example and the experimental example will be described below with reference to Fig. 4.

[63] As illustrated, in the general electric boiler according to the comparison example, the lower portion L and the upper portion U of the reservoir tub have maintained a temperature of about 9O⁰C at an initial state, that is, when a heating time is zero minute. Therefore, the general electric boiler has discharged hot water of about 88.7⁰C to the entry of the heating pipe. According to the general electric boiler, the discharged hot water of about 88.7⁰C has been used for a heating operation, then cooled to about 47⁰C, and has flowed back to the reservoir tub through an exit of the heating pipe.

[64] Also, when the general electric boiler operates (is heated) for about two minutes as illustrated, the lower portion L of the reservoir tub has maintained a temperature of about 88⁰C due to low temperature water that has flowed back to the reservoir tub through the heating pipe as illustrated. Also, the upper portion U of the reservoir tub has maintained a temperature of 88⁰C due to the initial residual hot water of 88.7⁰C. At this point, the initial hot water of about 88.7⁰C remains at the entry of the heating pipe, and hot water of about 89⁰C has been discharged to the entry of the heating pipe as the electric heater heats stored low temperature water. Also, after the discharged hot water is used for a heating operation, it has been cooled to about 53⁰C and has flowed back to the reservoir tub through the exit of the heating pipe.

[65] When the general electric boiler operates (is heated) for about twelve minutes as illustrated, the lower portion L of the reservoir tub has maintained a temperature of about 75°C as low temperature water that has been cooled by the heating pipe has continuously flowed to the lower portion L. That is, in the general electric boiler, since cooled low temperature water continuously flows to the lower portion L of the reservoir tub, the temperature of the lower portion L has lowered more and more as a time has elapsed. However, the temperature of the lower portion L of the reservoir tub has not lowered down to about 75°C or below.

[66] Also, the upper portion U of the reservoir tub has maintained a temperature of 84°C as the low temperature water is heated by the electric heater. Also, as the electric heater heats the stored low temperature water, hot water of about 88°C has been discharged to the entry of the heating pipe. Moreover, after the discharged hot water has been used for a heating operation, it has been cooled to about 60⁰C, and then has flowed back to the reservoir tub through the exit of the heating pipe.

[67] On the other hand, in the electric boiler according to the second embodiment of the present invention applied to the experimental example, the lower portion L of the reservoir tub have maintained a temperature of about 90⁰C at an initial state, that is, when a heating time is zero minute. Also, the separation chamber has maintained a temperature of about 97°C due to hot water heated by the electric heaters. Also, the water intake chamber has maintained a temperature of about 93.2°C due to hot water of the separation chamber guided by the hot water supply pipe. Therefore, the electric boiler according to the experimental example has discharged hot water of about 90⁰C to the entry of the heating pipe. Also, after hot water discharged at about 90⁰C has been used for a heating operation, the hot water has been cooled to about 56°C, and then has flowed back to the reservoir tub through the exit of the heating pipe. That is, since the electric boiler according to the experimental example discharges hot water of higher temperature than hot water discharged from the electric boiler according to the comparison example, the temperature of the hot water flowing back to the reservoir tub is also higher than temperature of the hot water of the comparison example.

[68] Also, when the electric boiler according to an experimental example operates (is heated) for about two minutes as illustrated, the lower portion L of the reservoir tub has maintained a temperature of about 94.5°C due to high heat of the electric heaters mounted inside the separation chamber as illustrated. Also, the separation chamber has maintained a temperature of about 97.6°C due to hot water heated by the electric heater. Also, the water intake chamber has maintained a temperature of about 93.5°C due to hot water of the separation chamber that has been supplied by the hot water supply pipe. Therefore, the electric boiler according to the experimental example has discharged hot water of about 92°C to the entry of the heating pipe. Also, after hot water discharged at about 92°C has been used for a heating operation, the hot water has been cooled to about 59°C, and then has flowed back to the reservoir tub through the exit of the heating pipe.

[69] When the electric boiler according to the experimental example operates (is heated) for about twelve minutes as illustrated, the lower portion L of the reservoir tub has maintained a temperature of about 94.3⁰C due to high heat of the electric heaters mounted inside the separation chamber. Also, the separation chamber has maintained a temperature of about 94⁰C due to hot water heated by the electric heater. Also, the water intake chamber has maintained a temperature of about 97⁰C due to hot water of the separation chamber that has been supplied by the hot water supply pipe, and hot air of the electric heater. Therefore, the electric boiler according to the experimental example has discharged hot water of about 92⁰C to the entry of the heating pipe. Also, after hot water discharged at about 92⁰C has been used for a heating operation, the hot water has been cooled to about 64⁰C, and then has flowed back to the reservoir tub through the exit of the heating pipe.

[70] Consequently, the general electric boiler according to the comparison example was not actually able to discharge hot water of about 88⁰C or more. Also, in the case where the general electric boiler operates continuously, it has discharged hot water of about 84⁰C constantly. On the other hand, the electric boiler according to the second embodiment of the present invention applied to the experimental example has actually immediately discharged hot water of about 9O⁰C or more right after its operation. Therefore, since the electric boiler according to the second embodiment of the present invention discharges hot water of higher temperature than temperature of hot water of the general electric boiler, the electric boiler according to the second embodiment of the present invention has showed remarkably higher thermal efficiency and heating efficiency than those of the general electric boiler.

[71] Meanwhile, according to a separately performed experiment, since the general electric boiler should heat low temperature water in the reservoir tub while allowing convention of the entire low temperature water in case of reheating hot water after the hot water in the reservoir tub is completely cooled, about one hour has been consumed to entirely heat the low temperature water. Therefore, the general electric boiler was able to perform a heating operation after about one hour should elapse since its re- operation.

[72] Meanwhile, since the electric boiler according to the second embodiment of the present invention discharges hot water of about 9O⁰C in only about three to four minutes even when the hot water in the reservoir tub is completely cooled, it was able to actually perform a heating operation right after reoperation.

[73] Meanwhile, Fig. 5 is a vertical cross-sectional view of an electric boiler according to a third embodiment of the present invention. The electric boiler according to the third embodiment is almost the same as the electric boiler according to the first embodiment. Only difference is that a portion through which high temperature water is discharged is differently configured, and a hot water coil 180, which will be described below is installed. Therefore, the only difference will be described below with reference to the accompanying drawings.

[74] As illustrated, the electric boiler according to the third embodiment of the present invention discharges high temperature water through a drainpipe 140. That is, the drainpipe 140 drains high temperature water supplied from a hot water supply pipe 70 directly to the outside of the reservoir tub 50.

[75] The drainpipe 140 drains the high temperature water to the outside using pumping pressure of a heating pump (not shown). Of course, the high temperature water drained to the outside of the reservoir tub 50 flows into the heating pipe (not shown) to perform a heating operation, and then flows back to the reservoir tub 50 through a water pipe 52 in the lower portion of the reservoir tub 50. That is, after high temperature water performs a heating operation through the heating pipe, it flows back to the reservoir tub 50 and is rapidly heated, and then supplied back to the heating pipe, so that the high temperature water circulates.

[76] Here, the drainpipe 140 may be formed at the end of the hot water supply pipe 70 as illustrated. The drainpipe 140 can be manufactured separately from the hot water supply pipe 70 as illustrated, and integrally connected to the hot water supply pipe 70 through welding or screw coupling. Unlike this, the drainpipe 140 can be formed as illustrated by extending long the end of the hot water supply pipe 70 and bending the upper end. Of course, one end of the drainpipe 140 is connected to the hot water supply pipe 70 and the other end of the drainpipe 140 is inserted into an outlet 54 of the reservoir tub 50 as illustrated. Therefore, the drainpipe 140 directly drains high temperature water of the hot water supply pipe 70 to the outside of the reservoir tub 50.

[77] Meanwhile, the electric boiler according to the third embodiment of the present invention further includes a drained water supplement unit. The drained water supplement unit supplies a portion of water stored in the upper portion of the reservoir tub 50 to the drainpipe 140. The reason the drained water supplement unit supplies water to the drainpipe 140 is for allowing flux corresponding to the pumping pressure of the heating pipe (not shown) acting on the drainpipe 140 to be supplied to the drainpipe 140.

[78] More specifically, the drainpipe 140 should drain the high temperature water of the hot water supply pipe 70 to the heating pipe using the pumping of the heating pipe. However, since only water separated by a separation chamber 62 of a water heater 60 is supplied to the hot water supply pipe 70, the drainpipe 140 does not receive an amount of water corresponding to a pumping amount of the heating pipe. Therefore, the drained water supplement unit supplies a portion of water stored in the upper portion of the reservoir tub 50 to the drainpipe 140 so that the drainpipe 140 receives and drains water corresponding to a pumping amount of the heating pump. Therefore, the drainpipe 140 drains water sufficiently corresponding to the pumping amount of the heating pipe.

[79] The drained water supplement unit, for example, can be realized as a flux supplement member 162 provided in one side of the drainpipe 140 to communicate with the inner upper portion of the reservoir tub 50 as illustrated and supply water stored in the upper portion of the reservoir tub 50 to the drainpipe 140. The flux supplement member 162 can be formed as a tube type pipe as illustrated, or formed as a hole 164 enlarged in the drawing.

[80] The flux supplement member 162 supplements an amount of water drained by the drainpipe 140. Therefore, the drainpipe 140 supplies a sufficient amount of water to the heating pipe (not shown).

[81] Meanwhile, the electric boiler according to the third embodiment of the present invention needs to further include a bathroom hot water processing member processing bathroom hot water separately from hot water for heating use drained from the drainpipe 140.

[82] The bathroom hot water processing member may be configured to substantially process bathroom hot water using hot air of the water heater 60. The bathroom hot water processing member, for example, can be formed as a hot water coil 180 wound on the hot water supply pipe 70 to process bathroom hot water using the temperature of the hot water supply pipe 70 as illustrated. That is, the hot water coil 180 heats water therein using hot air of the hot water supply pipe 70 through which high temperature water of the water heater 60 flows. Therefore, the hot water coil 180 supplies high temperature hot water to a bathroom or a kitchen (not shown).

[83] The hot water coil 180 can be manufactured separately from the hot water supply pipe 70 and wound on the hot water supply pipe 70 as illustrated. Unlike the illustration, the hot water coil 180 can be directly connected to the hot water supply pipe 70 or the drainpipe 140 to communicate with it so that the hot water flowing through the hot water supply pipe 70 or the drainpipe 140 is directly supplied to the bathroom or the kitchen. That is, when wound on the hot water supply pipe 70, the hot water coil 180 can heat cool water supplied from the outside using hot air of the hot water supply pipe 70. Unlike this, when the hot water coil 180 communicates with the hot water supply pipe 70 or the drainpipe 140, the hot water coil 180 can directly drain high temperature water of the hot water supply pipe 70 or the drainpipe 140. However, it is preferable that the hot water coil 180 is wound on the hot water supply pipe 70 as illustrated so that hot water for heating use is prevented from being drained as a bathroom hot water during a heating operation. [84] The electric boiler according to the third embodiment of the present invention supplies water of the reservoir tub 50 rapidly heated by the water heater 60 to the drainpipe 140 through the hot water supply pipe 70. Therefore, the drainpipe 140 supplies the high temperature water to the heating pipe (not shown) to heat an indoor space.

[85] At this point, the drained water supplement unit including the flux supplement member 162 supplies a portion of water stored in the upper portion of the reservoir tub 50 to the drainpipe 140 so that high temperature water is swiftly drained to the drainpipe 140. Therefore, the drainpipe 140 secures flux corresponding to the pumping pressure of a heating pump (not shown). Of course, the drainpipe 140 swiftly drains high temperature water as flux corresponds to the pumping pressure.

[86] Meanwhile, the hot water supply pipe 70 and the drainpipe 140 heat water stored in the upper portion of the reservoir tub 50 using high temperature water flowing through the hot water supply pipe 70 and the drainpipe 140. That is, the hot water supply pipe 70 and the drainpipe 140 not only drain high temperature water to the heating pipe (not shown) if necessary, but also heats water stored in the reservoir tub 50 using high temperature of its own.

[87] Meanwhile, the hot water coil 180 wound on the hot water supply pipe 70 is heated by the hot air of the high temperature water flowing through the hot water supply pipe 70. Therefore, the hot water coil 180 supplies hot water to the bathroom or the kitchen (not shown).

[88] Meanwhile, Fig. 6 is a vertical cross-sectional view of an electric boiler according to a fourth embodiment of the present invention. The electric boiler according to the fourth embodiment is almost the same in its construction as that of the electric boiler illustrated in Fig. 5. Only difference is that a water intake chamber 80 is installed at the upper end of the hot water supply pipe 70. Therefore, the only difference will be described with reference to the accompanying drawings.

[89] As illustrated, the electric boiler according to the fourth embodiment of the present invention includes the water intake chamber 80 integrally interposed between the hot water supply pipe 70 and the drainpipe 140. At this point, one side of the water intake chamber 80 is connected to the upper end of the hot water supply pipe 70 through which high temperature water is drained, and the other side of the hot water supply pipe 70 is connected to the end of an inlet of the drainpipe 140 as illustrated. Therefore, the water intake chamber 80 takes in high temperature water of the hot water supply pipe 70 through its one side, and supplies the high temperature water to the drainpipe 140 through its other side.

[90] As the water intake chamber 80 is installed at the upper end of the hot water supply pipe 70 as illustrated, it is located in the upper portion of the reservoir tub 50. Therefore, the water intake chamber 80 takes in and diffuses the high temperature water that is guided by the hot water supply pipe 70 in the upper portion of the reservoir tub 50, and simultaneously, supplies the diffused high temperature water to the drainpipe 140.

[91] The reason the water intake chamber 80 is provided in the upper portion of the reservoir tub 50 is for the water intake chamber 80 to heat water stored in the upper portion of the reservoir tub 50 using hot air of high temperature water while diffusing the high temperature water supplied from the hot water supply pipe 70 to the upper portion of the reservoir tub 50. That is, the water stored in the upper portion of the reservoir tub 50 is indirectly heated by hot air emitted from the water intake chamber 80. Therefore, the water stored in the reservoir tub 50 is heated more quickly.

[92] Meanwhile, the flux supplement member 162 of the drained water supplement unit may be located on one side of the water intake chamber 80 to communicate with it as illustrated. Therefore, in the case where high temperature water is drained to the drainpipe 140 by the heating pump (not shown), the flux supplement member 162 supplies a portion of water stored in the upper portion of the reservoir tub 50 to the drainpipe 140 through the water intake chamber 80.

[93] In the case where the heating pump (not shown) does not operate, the flux supplement member 162 drains high temperature water due to water pressure of the high temperature water flowing to the water intake chamber 80. Therefore, the high temperature water drained through the flux supplement member 162 heats low temperature water while mixing with the low temperature water existing in the upper portion of the reservoir tub 50.

[94] Here, discharge holes 80a illustrated in Fig. 3 can be formed in the water intake chamber 80, separately from the flux supplement member 162. In the case where the discharge holes 80a are formed, the water intake chamber 80 more swiftly heats the low temperature water in the upper portion of the reservoir tub 50.

[95] Meanwhile, Fig. 7 is a vertical cross-sectional view of a backward flow suppression member installed to the water heater of Figs. 5 and 6. The backward flow suppression member will be described below with reference to th4e accompanying drawings.

[96] As illustrated, in the water heater 60, water of the reservoir tub 50 flows through a plurality of through holes 62a and then is separated. However, when the separated water is heated, the heated water flows backward and is drained through the through holes 62a due to a temperature difference. Therefore, the electric boiler according to an embodiment of the present invention needs to have a backward flow suppression member.

[97] Since the backward flow suppression member is integrally formed in the water heater 60 while communicating with the water heater 60, it is formed in a structure permitting the water of the reservoir tub 50 to be supplied to the through holes 62a of the water heater 60, and preventing introduced water from flowing backward. Accordingly, the backward flow suppression member is configured to restrain the heated water separated inside the water heater 60 from flowing backward to the through holes 62a due to a temperature difference. That is, the backward flow suppression member permits water to flow to the water heater 60, and restrain water from flowing backward.

[98] The backward flow suppression member can be formed as a suction chamber 126 including suction holes 126a on its one side. The suction holes 126a are integrally installed with the separation chamber 62 of the water heater 60 to shield the through holes 62a, and communicates with the through holes 62a while substantially forming a right angle to the through holes 62a. The suction chamber 126 suctions the water stored in the reservoir tub 50 through the suction holes 126a and supplies the water to the through holes 62a. That is, the water suctioned to the suction holes 126a of the suction chamber 126 is bent perpendicularly and flows into the through holes 62a.

[99] Therefore, since water introduced to the separation chamber 62 should be bent perpendicularly from the through holes 62a in order to be discharged through the suction holes 126a even when the water is heated, backward flow is substantially impossible. That is, the suction holes 126a of the suction chamber 126 form a right angle to the through holes 62a, a height difference for preventing backward flow is substantially provided on the outer side of the separation chamber 62.

[100] Here, to more definitely restrain water flowing backward from the separation chamber 62 from being drained to the outside of the suction chamber 126, the suction holes 126a may be formed in the upper lateral portion of the suction chamber 126 as illustrated in the enlarged portion A of the drawing. The suction holes 126a can be formed in the lower lateral portion of the suction chamber 126 as illustrated by a dotted line in the enlarged portion A. Of course, the suction holes 126a can be formed in both the upper lateral portion and the lower lateral portion of the suction chamber 126. Also, a plurality of through holes 62a of the separation chamber 62 may be provided as illustrated so that low temperature water taken in the suction chamber 126 is more swiftly introduced.

[101] Unlike the foregoing, the backward flow suppression member, for example, as illustrated in the enlarged portion B of the drawing, can be formed as a suction pipe 128. The suction pipe 128 is inserted into the separation chamber 62 of the water heater 60 with its both ends exposed. Suction holes 128a suctioning water of the reservoir tub 50 are formed in the both exposed ends. The suction pipe 128 includes supply holes 128b. The supply holes 128b form a right angle to the suction holes 128a and supply water suctioned to the suction holes 128a to the separation chamber 62. That is, the suction pipe 128 is mounted inside the separation chamber 62, and the suction holes 128a and the supply holes 128b are formed in the both ends and the upper portion of the suction pipe 128. Therefore, the suction pipe 128 suctions water through the suction holes 128a and supplies water to the separation chamber 62 through the supply holes 128b. At this point, the water suctioned to the suction holes 128a is bent perpendicularly and then supplied to the separation chamber 62 through the supply holes 128b. Of course, since the water supplied to the supply holes 128b should be bent and then drained to the suction holes 128a upon backward flow, the water is not drained swiftly and backward flowing is substantially suppressed.

[102] Here, the suction holes 128a can be formed in the upper portion on both sides of the suction pipe 128 as enlarged in the drawing. Unlike this, the suction holes 128a can be formed in the lower portion on both sides of the suction pipe 128 as illustrated by a dotted line in the enlarged drawing. Also, the suction holes 128a can be formed by completely opening both ends of the suction pipe 128.

[103] Consequently, the water that has flowed into the suction chamber 126 or the suction pipe 128 cannot be easily drained to the outside. Therefore, the water separated by the separation chamber 62 is not drained by backward flow. Industrial Applicability

[104] As described above, in an electric boiler according to the present invention, a water heater rapidly heats low temperature water to generate high temperature water rapidly, and a hot water supply pipe supplies high temperature hot water to a drainpipe of a reservoir tub, so that a heating operation can be immediately performed. Since the heating operation is performed using high temperature hot water rapidly heated to about 94⁰C, an indoor space can be continuously heated to 2O⁰C or more. Also, since the high temperature hot water rapidly heated to about 94⁰C flows back to the reservoir tub after performing the heating operation, not only low temperature water of higher temperature than that in the related art can be supplied to the lower portion of the reservoir tub, but also the temperature of the lower portion of the reservoir tub can be maintained higher than that in the related art.

[105] Also, since high temperature hot water guided to the upper portion of the reservoir by the hot water supply pipe heats low temperature water in the lower portion of the reservoir while performing convection due to a temperature difference, not only the low temperature water stored in the reservoir can be entirely heated and heat can be stored in a short time, but also electricity consumed for heating the low temperature water can be remarkably reduced.

[106] Also, since the low temperature water is simultaneously and respectively heated by a plurality of electric heaters in the case where a water heater includes the plurality of electric heaters, the low temperature water can be more quickly heated to high temperature. Furthermore, in the case where a baffle is provided between the plurality of electric heaters, simultaneously and respectively heated hot water is reheated repeatedly, so that the low temperature water can be heated to high temperature more rapidly.

[107] Furthermore, in the case where the water intake chamber is provided at the upper end of the hot water supply pipe, high temperature hot water heated by the water heater is uniformly entirely distributed to the upper portion and the uppermost end of the reservoir tub.

[108] Also, in the case where the circulation member circulating hot water is provided, high temperature hot water heated by the water heater is forcibly circulated to the lower portion of the reservoir tub, so that the low temperature water in the reservoir tub can be heated very rapidly and entirely.

[109] In addition, in the case where the drainpipe is provided, the drainpipe directly supplies high temperature water heated by the water heater and supplied to the hot water supply pipe to the heating pipe (not shown), so that the high temperature water heated using high heat can be used as heating water without heat loss.

[110] Particularly, since the drained water supplement unit supplies a portion of water stored in the reservoir tub to the drainpipe, the drainpipe can swiftly drain high temperature water.

[I l l] Also, in the case where the backward flow suppression member is provided, the backward flow suppression member prevents water separated by the water heater from flowing backward, so that high temperature water rapidly heated by the water heater is prevented from flowing backward and losing heat.

[112] Furthermore, in the case where the water intake chamber is provided between the hot water supply pipe and the drainpipe, water stored in the upper portion of the reservoir tub can be heated using high temperature water supplied from the hot water supply pipe. In the case where the bathroom hot water processing member is provided, bathroom hot water can be provided using hot air of the water heater, separately from the heating water.

Claims

[1] An electric boiler performing a heating operation while changing low temperature water flowing from an outside into high temperature water using electricity, and draining the high temperature water using a pumping pressure of a heating pump, the electric boiler comprising: a reservoir tub (50) whose four sides are closed, storing low temperature water flowing into an inlet (52) provided in one side, and heating the stored low temperature water to high temperature to drain the heated water through an outlet

(54) provided in an upper portion; a water heater (60) separating a portion of the low temperature water stored in the reservoir tub (50) and rapidly heating the separated low temperature water to high temperature using electricity supplied from an outside; and a hot water supply pipe (70) guiding the high temperature water rapidly heated by the water heater (60) to an upper portion of the reservoir tub (50) to supply the high temperature water to the upper portion of the reservoir tub (50) and the outlet (54) of the reservoir tub (50).

[2] The electric boiler of claim 1, wherein the water heater (60) comprises: a separation chamber (62) integrally mounted in a lower portion of the reservoir tub (50), receiving a portion of low temperature water stored in the lower portion of the reservoir tub (50) through a through hole (62a) formed in its one side, separating the received water, and supplying the separated portion of the lower temperature water to the upper portion of the reservoir tub (50) through the hot water supply pipe (70) integrally connected to its other side; and an electric heater (64) mounted inside the separation chamber (62) to heat the water separated by the separation chamber (62) to high temperature while emitting heat using electricity supplied from an outside.

[3] The electric boiler of claim 2, wherein the water heater (60) comprises a plurality of electric heaters (64) configured to heat the water separated inside the separation chamber (62) simultaneously and respectively.

[4] The electric boiler of claim 3, further comprising a baffle (66) between the plurality of electric heaters (64) inside the separation chamber (62) to separate the electric heaters (64) in a closing manner such that the water separated by the separation chamber (62) flows between the electric heaters (64).

[5] The electric boiler of claim 1, further comprising a water intake chamber (80) taking in and diffusing high temperature hot water guided to the hot water supply pipe (70) through its one side to which an end of a discharge side of the hot water supply pipe (70) is connected in the upper portion of the reservoir tub (50), and providing the diffused hot water to the upper portion of the reservoir tub (50) through a discharge hole (80a) formed in its other side.

[6] The electric boiler of claim 1, further comprising a circulation member (90) allowing high temperature hot water guided to the upper portion of the reservoir tub (50) by the hot water supply pipe (70) to circulate to a lower portion of the reservoir tub (50), the circulation member (90) comprising: a bypass pipe (92) connected from the upper portion to the lower portion of the reservoir tub (50) to allow the high temperature hot water guided to the upper portion of the reservoir tub (50) to flow to the lower portion of the reservoir tub

(50); and a circulation pump (94) pumping the high temperature water flowing through the bypass pipe (92) to allow the water to circulate to the lower portion of the reservoir tub (50).

[7] The electric boiler of claim 1, further comprising: a drainpipe (140) whose one end is connected to the outlet (54) of the reservoir tub (50) and whose other end is connected to the hot water supply pipe (70) to drain high temperature hot water supplied by the hot water supply pipe (70) to the outlet (54) using the pumping pressure of the heating pipe; and a drained water supplement unit supplying water stored in the upper portion of the reservoir tub (50) to the drainpipe (140) such that flux corresponding to the pumping pressure of the heating pipe acting on the drainpipe (140) is provided to the drainpipe (140).

[8] The electric boiler of claim 7, wherein the drained water supplement unit comprises a flux supplement member (162) provided on one side of the drainpipe (140) to communicate with an inner upper portion of the reservoir tub (50), and to supply the water stored in the upper portion of the reservoir tub (50) to the drainpipe (140).

[9] The electric boiler of claim 7, further comprising a water intake chamber (80) integrally interposed between the hot water supply pipe (70) and the drainpipe (140), and whose one side is connected to an end of a discharge side of the hot water supply pipe (70), and whose other side is connected to an end of an inlet side of the drainpipe (140), the water intake chamber (80) taking in and diffusing high temperature hot water guided to the hot water supply pipe (70) from the upper portion of the reservoir tub (50), and simultaneously, supplying the diffused high temperature hot water to the drainpipe (140).

[10] The electric boiler of claim 1, further comprising a backward flow suppression member integrally formed with the water heater (60) to communicate with the water heater (60), the backward flow suppression member having such a structure as to permit water of the reservoir tub (50) to flow to a through hole (62a) of the water heater (60), and to restrain introduced water from flowing backward, thereby preventing separated and heated water in the water heater (60) from flowing backward to the through hole (62a).

[11] The electric boiler of claim 10, wherein the backward flow suppression member comprises a suction chamber (126) integrally installed in the water heater (60) to shield the through hole (62a) and including a suction hole (126a) substantially forming a right angle to the through hole (62a) and communicating with the through hole (62a), the suction chamber (126) suctioning water stored in the reservoir tub (50) through the suction hole (126a) to supply the water to the through hole (62a).

[12] The electric boiler of claim 10, wherein the backward flow suppression member comprises a suction pipe (128) inserted into the water heater (60) with its both ends exposed, suction holes (128a) suctioning water of the reservoir tub (50) being formed in the exposed both sides, and supply holes (128b) substantially forming a right angle to the suction holes (128a) and supplying the water suctioned to the suction holes (128a) to the separation chamber (62) being formed in the suction pipe (128).

[13] The electric boiler of one of claims 1 to 12, further comprising a bathroom hot water processing member providing bathroom hot water separately from hot water for a heating operation provided through the outlet (54) of the reservoir tub (50), the bathroom hot water processing member comprising a hot water coil (180) substantially processing the bathroom hot water using hot air of the water heater (60).