FR3001285A1 - Electric boiler for water storage and heating installation, has water circulation blocks including two sets of internal water circulation channels to form two independent internal water circuits, respectively - Google Patents

Abstract

The boiler (1) has water circulation blocks (2) stacked on each other and crossed by a set of internal water circulation channels extending through the blocks to form an internal water circuit (16). The blocks include electrical resistors (3) for heating the water in the internal water circulation channels, where the resistors are connected individually to a regulating case (4) for adjusting the heating power. The blocks include another set of internal water circulation channels connected in series to form another internal water circuit (16a) independent of the former water circuit. Independent claims are also included for the following: (1) a water storage and heating installation (2) a central heating installation.

Description

The present invention relates to an electric boiler with two internal water circuits, a heating and water storage system comprising a hot water tank and such a boiler and a central heating installation. More particularly, the heating and water storage installation comprises a hot water tank, while the central heating installation comprises a buffer tank. Advantageously, the hot water tank and the buffer tank may be heated individually or in combination by a coolant circuit connected to an auxiliary heating source which may be solar. Many types of electric boiler are known, including boilers containing modular heating blocks. For example, it is known a water circulation electric boiler comprising several modular blocks of metal or alloy good conductor of heat stacked on top of each other. Each modular block comprises a water circuit and an electrical heating resistor, the water circuits of the modular blocks being connected in parallel.

The document FR-A-2 892 500 describes a water-circulating electric boiler comprising a plurality of modular blocks of metal or alloy that are good conductors of heat stacked on top of one another, each block being traversed by a first internal circulation channel. water, the first channel of a block being connected in series to the first channel passing through the upper block to form a first internal circuit of water to the boiler, each modular block having an electrical heating resistor for heating the water the first channel therethrough, the electrical resistors being individually connected to a control box for switching a variable number of resistors to adjust the heating power. Connecting the channels of the modular blocks in series facilitates installation, modularity, ie adaptation to the desired power and regulation of the heating power. However, the application of such an electric boiler is essentially reserved for central heating or a single use, so that all the possibilities offered by the use of modular blocks and water circuits passing through the boiler and connected in series are not exploited.

The problem underlying the present invention is to allow an electric boiler for example as described above to combine several. For this purpose, according to the invention, there is provided a water-circulating electric boiler comprising a plurality of modular blocks stacked one on top of the other, each block being traversed by a first internal water circulation channel, the first water channel. a block being connected to the first channel passing through the upper block to form a first internal water circuit in the boiler, at least two modular blocks each comprising an electrical heating resistor for heating the water of the first channel passing therethrough, the electrical resistors being connected individually to a regulation box ensuring the switching on of a variable number of resistors to adjust the heating power, characterized in that each block comprises a second internal water circulation channel, the second channels being connected in series so as to form a second internal circuit of water to the boiler, the second circuit being independent of the first r circuit. The technical effect obtained due to the presence of a second circuit internal to the boiler, having a second channel for each modular block, is to be able to use the resistive heating of the boiler for another purpose than for heating the first circuit. internal. This increases the energy balance of the whole and can group together in a single boiler two boilers respectively dedicated to a specific use.

Advantageously, the first internal channel of each block comprises a first spiral tube embedded in the material of said block and the second internal channel of each block comprises a second spiral tube embedded in the material of said block, one of the tubes surrounding the other tubing . Advantageously, a pipe of an internal channel forms, from an outermost turn, turns narrowing towards the middle of the modular block and then turns widening towards the outermost turn, the tubing of the other internal channel at least partially surrounding the outermost turn. Advantageously, the first and second internal channels of a block are respectively connected to the first and second internal channels of an adjacent block by a bend, the set of first channels of the blocks and their associated bends forming the first internal circuit while the set of second channels of the blocks and their associated bends forming the second internal circuit, at least the bends associated with one of the internal circuits having a connector for connecting and disconnecting each internal channel of the associated bend.

Advantageously, at least the bends associated with one of the internal circuits are internal to two adjacent modular blocks. Advantageously, each block comprises a plate of electrically insulating refractory material in which the electrical resistance is embedded, this plate being incorporated in the lower face of said block, the first and second internal channels of each block extending above said plate.

The invention also relates to a heating and water storage installation comprising a hot water tank and at least one pre-heating source of the water contained in the tank, characterized in that the heating source of the tank water is such an electric boiler, the water inlet of the hot water tank being connected to the second internal water circuit of the electric boiler. Thus, in addition to a use dedicated to a heating installation that can be a central heating installation, the present invention allows an additional use of the boiler for heating a hot water tank, an internal circuit of water of the boiler dedicated to him.

Advantageously, the hot water tank comprises in its interior a heat exchanger in which circulates a heat transfer fluid from an auxiliary heating source external to the hot water tank, a heat transfer fluid circuit connecting the auxiliary heating source at the exchanger, a circulator being provided in the coolant circuit. This allows additional heating of the hot water tank.

Advantageously, the auxiliary heating source is a solar collector heating source. This saves energy as well as a process of ecological heating, the boiler no longer ensuring the heating of the hot water tank and solar energy being a renewable energy par excellence. Advantageously, the heat transfer fluid circuit passes through a buffer tank filled with water, a heat exchanger being provided in the buffer tank for heating the water it contains by the passage of the heat transfer fluid from the auxiliary source of heating, the buffer tank and the hot water tank being arranged in series in the coolant circuit. Advantageously, the heat transfer fluid circuit comprises a bypass, this bypass allowing the passage of the heat transfer fluid directly from the auxiliary heating source to the hot water tank without passing through the buffer tank, a three-way valve being provided in the cooling circuit. coolant. This makes it possible to heat only the hot water tank when the auxiliary energy is not sufficient to heat the two balloons or when it is unnecessary to heat up the buffer tank.

Advantageously, the buffer tank rests on the upper face of a block of the electric boiler, heat transfer from the block to the buffer tank. It is thus carried out a recovery of the energy released by the boiler. Advantageously, the water contained in the buffer tank has been previously heated in the electric boiler, the water inlet of the buffer tank being connected to the first internal circuit of water to the electric boiler.

Finally, the invention relates to a central heating installation having at least one heating means of the radiator type in a central heating circuit for the circulation of heated water, characterized in that it is associated with a previously described installation comprising such a device. buffer tank.

Advantageously, the buffer tank comprises at least one temperature probe, the temperature sensor being connected to the control box of the electric boiler and advantageously a second temperature sensor, the second temperature sensor being connected to a thermostat regulating the temperature in the boiler. central heating circuit.

Other features, objects and advantages of the present invention will appear on reading the detailed description which follows and with reference to the appended drawings given as non-limiting examples and in which: - Figure 1 is the sectional diagram a central heating installation comprising a buffer tank and an electric boiler according to one embodiment of the present invention, the boiler also providing heating of the water of a heating and water storage installation comprising a balloon of hot water, - Figure 2 is a sectional view in an exploded vertical plane showing an embodiment of the different modular blocks of an electric boiler according to the present invention, - Figure 3 is a sectional view in a vertical plane showing the different modular blocks according to the embodiment of the electric boiler shown in Figure 2, these blocks being stacked and fixed one by one 4 is a sectional view in a horizontal plane of an embodiment of a modular block and its connection connectors in a boiler according to the present invention, this figure showing the first and second channels. internal winding in the modular block, - Figure 5 is a sectional view of a modular block along the plane BB of Figure 4. Figure 1 schematically shows a central heating system comprising a boiler 1 electric water circulation comprising a plurality of modular blocks 2 whose core may be metal or alloy good heat conductor, the blocks 2 being stacked on each other preferentially in the direction of their length. For simplicity, a single modular block, namely the lower modular block, is referenced 2 in Figure 1 but this reference applies to all blocks. Such a modular block comprises first and second lateral sides 2a, 2b as well as an upper face and a lower face 2c, these faces also being the longitudinal faces of the block 2. Advantageously, at least the upper or lower block can present its face respectively upper or lower 2c, or that facing the outside of the boiler 1, coated with a refractory material. These modular blocks 2 will be better seen in Figure 2, which shows the modular blocks 2 are shown separated from each other, which is not their position when they are mounted in the boiler 1 electric. The blocks 2 may be similar or not. Each modular block 2 comprises a first internal channel 5 and a second internal channel 5a, these channels 5, 5a being referenced only for the lower modular block 2 but being present in each modular block of the electric boiler 1. The first internal channel 5 of each modular block 2 is connected to the respective channel of an adjacent modular block to form a first internal water circuit 16. The first internal water circuit 16 is continuous throughout the electric boiler 1, advantageously crossing all the modular blocks of the electric boiler from the water inlet of the electric boiler 1 and towards its water outlet. It is the same for the second channels 5a forming a second internal circuit 16a of water in the electric boiler 1. In FIG. 1, for each modular block 2, its first and second channels 5, 5a are shown in the respective form of a rectilinear channel passing through each block 2 of a 2a of its lateral faces 2a, 2b towards its other lateral face. 2b. This is only a symbolic representation of the path of the channels 5, 5a in the block 2, these channels 5, 5a winding the associated block 2 in the dimension of the block 2 not shown in FIG. 1, that is to say in a plane parallel to the plane of the lower face 2c or longitudinal upper block 2. This will be better seen in Figures 2 to 4. In each modular block 2, there is provided an electric heater 3 for heating water passing through the first and second channels 5, 5a. For example, without being limiting, the electric heating resistors 3 may each be 1,000 Watts. The electrical resistors 3 are individually connected to a control box 4 for switching on a variable number of resistors to adjust the heating power. The control box 4 can advantageously supply the electrical resistors 3 by rotary bearing. The modular blocks 2 are advantageously of parallelepipedal shape and are in contact with each other by one of their longitudinal faces, a lower face 2c of a block 2 resting on the upper face of the supporting block. This arrangement ensures excellent thermal contact between the different modular blocks 2. Also preferably, the modular blocks 2 are removably attached to each other. It is thus possible to easily adapt the maximum power of the boiler 1 by modifying the number of modular blocks 2. The illustrated stacking direction is vertical but this case is not limiting. The first water circuit 16 of the boiler 1 can be supplied with water flowing in a central heating circuit, this heating circuit having at least one radiator. The second water circuit 16a of the boiler 1 is fed with cold water with a heated water outlet in the boiler connected to a hot water tank 7.

Starting respectively from a respective input 18, 18a of water inlet to the boiler 1, the first and second internal circuits 16, 16a of water penetrate into the first lower modular block 2, that is to say the lowest modular block of the stack of modular blocks 2. For this first lower block 2, the first water circuit 16 advantageously penetrates by a lateral side 2a of the lower block while the second circuit 16a advantageously penetrates by the lower longitudinal side 2c of the block 2, this by a portion of this face 2c adjacent to the same lateral side 2a. The first and second internal circuits 16, 16a pass through the lower modular block 2 from one lateral side 2a to the other lateral side 2b, advantageously this without this path being direct in the block 2. This is done respectively by a first channel For the first internal circuit 16 and by a second channel 5a for the second internal circuit 16a, the first and second channels 5, 5a advantageously snaking into the block 2. For the first lower modular block 2, the first and second internal circuits 16 , 16a leave the block 2 by the other lateral side 2b to enter the second block which is directly superimposed on it, this by the same lateral side 2b.

In the embodiment illustrated in FIG. 1, for the second modular block 2 and for the modular blocks associated with an even number, that is to say the fourth block, the sixth block, etc., of such blocks 2 2b, through which the first and second water internal circuits 16, 16a of the boiler 1 enter. On the other side, in this embodiment of the invention, on the other lateral side 2a, a single circuit internal 16 goes out to enter the third block by the same lateral side 2a. The other internal circuit 16a exits through the upper longitudinal face of the second block to enter the third block by its lower longitudinal face which rests on this upper longitudinal face of the second block.

For this third block, on the lateral side 2b, the outputs of the internal circuits 16, 16a are similar to those of the first lower modular block 2. This is valid for all successive odd modular blocks, ie the fifth and seventh blocks, and so on. This is only one embodiment of the path of the first and second internal circuits 16, 16a in the boiler 1. Alternatively, these internal circuits 16, 16a can enter a block 2 by a lateral side 2a or 2b of said block and come out on the same side, this can be seen in the embodiment of Figures 2 to 4. Between two modular blocks 2, one of which is directly superimposed on the other, there is provided a first elbow 23 and a second elbow 23a respectively for the first and second internal circuits 16, 16a, so that the water leaving a lower block is brought into the block which is directly higher. In the embodiment shown in FIG. 1, on a first lateral side 2b of all the blocks 2, thus forming a lateral side of the boiler 1, the two elbows 23, 23a are outside the blocks 2. On the other side 2a of all the blocks, a bend 23 is outside the blocks 2 while a second bend 23a is inside two superimposed blocks. As will be subsequently more precisely detailed, the outer bends 23 may be those of the first internal circuit 16, advantageously associated with a central heating installation, while the inner bends 23a may be those of the second internal circuit 16a, advantageously associated with a This is not necessarily the case, however. For the first internal water circuit 16, the electric boiler 1 comprises, in known manner, a water inlet 18 located on a lateral side 2a of the lower modular block 2 and a water outlet 21 located on a lateral side 2b of the upper modular block 2, these lateral sides 2a, 2b can be opposite as shown in Figure 1, which is not limiting. The water inlet 18 connected to the first internal circuit 16 can introduce into the boiler 1 the return water of the heating circuit of a central heating installation. The water outlet 21 of the first circuit 16 of the boiler 1 may lead to a first pipe 6 bringing the water from the boiler 1 to a buffer tank 8. The buffer tank 8 serves as an additional means of storage of water leaving the boiler 1 with possibility of heat exchange for the water contained in its interior. Advantageously, the buffer tank 8 contains an additional means of heating the water in its interior, the main or pre-heating source being constituted by the boiler 1. This additional means of heat exchange is advantageously constituted by a heat exchanger 14 heat exchanger disposed inside the buffer tank 8 in which exchanger 14 circulates a coolant. The heat transfer fluid comes from a fluid circuit 13 outside the buffer tank 8, which circuit will be detailed later. The buffer tank 8 advantageously has at least one temperature sensor 20 which is connected to the regulation box 4 for controlling the temperature in the heating circuit. Advantageously, a second temperature sensor 20 is connected to a thermostat 17 provided for regulating the temperature in the boiler 1, this temperature being between 30 and 80 ° C.

Advantageously, the buffer tank 8 rests on the longitudinal upper face, preferably covered with a refractory material, of the highest modular block 2 of the boiler 1. The buffer tank 8 can thus receive a heat transfer achieving a further heating of refill by the upper block 2 of the boiler 1, this additional heating being also achieved by stacking the modular blocks 2 of the boiler 1 electric. At the outlet of the buffer tank 8, the water it contains is fed via an outlet pipe 9 into the heating circuit, this circuit advantageously being that of a central heating installation. This circuit is not fully represented but symbolized by the outgoing arrow of the outlet pipe 9 and the arrow pointing to the heating water inlet 18 on the other side of the electric boiler 1 as that supplying the buffer tank 8. A circulator 15 is advantageously provided in the heating circuit for initiating a circulation of heated heating water leaving the electric boiler 1 through the central heating installation. At the outlet of the electric boiler 1, this heating circuit passes through the buffer tank 8 and returns to the water supply 18 of the electric boiler 1 after the water has lost calories in at least one heating means of the type radiator present on the heating circuit. In the circuit of the central heating installation, shown in Figure 1 on the water inlet pipe 18 to the boiler 1, there can be provided a purge valve 22 connected to an expansion tank 11, this purge valve 22 may be provided at a place other than to the inlet of the boiler 1. It can also be provided in this central heating circuit a three-way valve, not shown in Figure 1, with a branch of the circuit heating in parallel with said at least one radiator circuit. For its second internal water circuit 16a, the electric boiler 1 comprises a water inlet 18a also located on the lateral side 2a of the lower modular block 2 or on the lower face 2c of this lower block, this latter embodiment being shown in FIG. 1. The electric boiler 1 comprises a water outlet 21a located on a lateral side 2b of the upper modular block 2, in FIG. 1 the other lateral side 2b as the lateral side 2a of the water inlet , which is not limiting.

The water inlet 18a connected to the second internal circuit 16a of the boiler 1 introduces into the boiler 1 cold water (for example from a hydraulic network of a tap water dispenser) to heat it, this then heated water leaving the boiler 1 by the water outlet 21a of this second internal circuit 16a and being fed by a second pipe 6a feeding a hot water tank 7.

The water tank 7 and the boiler 1 are therefore part of a heating and water storage installation, the boiler 1 supplying another heating installation, previously described, with advantageously a buffer tank 8, this other installation being able to be a central heating installation. However, it is to be considered that the heating and water storage installation can also be used in combination with another installation than that of central heating. Thus, thanks to the first and second internal circuits 16, 16a passing through the blocks 2 of the electric boiler 1, the resistive heating by the resistors 3 of the boiler 1 is used for two purposes, which increases the energy balance of the boiler 1. The hot water tank 7 comprises an additional means for heating the water it contains by having received it from the boiler 1, a source (which may be main or prior) of heating being constituted by the boiler 1. This additional heating means is advantageously constituted by a heat exchanger 14a disposed inside the hot water tank 7, in which exchanger 14a circulates a heat transfer fluid. The heat transfer fluid comes from a fluid circuit 13 outside the hot water tank 7, this fluid circuit 13 being also advantageously that of the buffer tank 8. Advantageously, the heat exchangers 14, 14a of the buffer tank 8 and the balloon 7 hot water are copper. For purposes of order, the contents of the hot water tank 7 and the buffer tank 8 can be respectively 100 and 32 liters.

In a preferred embodiment of the present invention, the coolant fluid circuit 13, which fluid may be water, connects the buffer tank 8 and the hot water tank 7 to an auxiliary heating source 10 which heats the tank. heat transfer fluid and therefore the water contained respectively in the buffer tank 8 and the hot water tank 7.

This auxiliary heating source 10 is advantageously a heating source by solar collector, that is to say a solar thermal collector. Thus, this auxiliary source 10 is used in auxiliary heating as a second heating source other than the first heating source constituted by the electric boiler 1, which provides energy savings by being environmentally friendly. A circulator 15a is provided in the coolant fluid circuit 13 in order to initiate a circulation of fluid in this circuit 13 and thus a heat exchange between the auxiliary heating source 10 and the buffer tank 8 and / or the water tank 7. Advantageously, the hot water tank 7 and the buffer tank 8 are connected in series in the coolant circuit 13. It may be possible to reverse the circulation in the coolant circuit 13 to heat one of the balloons 7 or 8 before the other balloon 8 or 7, when there are not enough calories in the source heating auxiliary 10 for effectively heating the hot water tank 7 and the buffer tank 8. This can be done by reversing the pump direction of the pump 15a provided in the fluid circuit 13. It is also possible to disconnect individually the hot water tank 7 or the buffer tank 8 of this coolant fluid circuit 13. Thus, in the coolant circuit 13, there may be provided a bypass 13a, in a position of the three-way valve 12 positioned on the circuit 13, at least not to pass heat transfer fluid inside the balloon buffer 8, the heat transfer fluid then flowing between the auxiliary heating source 10 and the hot water tank 7. In an alternative, it is also possible to heat only the buffer tank 8 by the auxiliary energy source 10, the hot water tank 7 being disconnected from the heat transfer fluid circuit 13. In this case, the circulator 15a is to be positioned differently than as shown in FIG.

The hot water tank 7 comprises an outlet pipe 9a of hot water for the so-called sanitary hot water which may be at a temperature of around 50 ° C or less. As seen in Figure 2, the modular blocks 2 are advantageously removably attached to each other, the modular blocks being shown spaced apart in this figure. This makes it possible to modify the number of blocks to adapt the maximum power of the boiler as needed. The modular blocks 2 are preferably aluminum or aluminum alloy given the excellent thermal conductivity of these. In FIGS. 2 and 3, the part of the first internal circuit circulating in the boiler which is inside each block 2 is visible. As previously indicated, this first internal circuit consists of a series of first internal channels 5. , a first internal channel 5 being present in each modular block 2, a bend 23 connecting the first internal channels 5 between them input and output, the input and output can be made by the same bend. There is also provided a second internal channel 5a in each block 2, this second internal channel 5a being advantageously disposed on the periphery of the first internal channel 5. In the embodiment shown in FIGS. 2 and 3, the first internal circuit enters a block 2 by a lateral side 2a and spring by the same lateral side 2a. As previously mentioned, each internal channel 5 of each modular block 2 can meander in its interior. In FIGS. 2 and 3, the first internal channels 5 form turns in their associated block 2, these turns extending essentially in a plane parallel to the plane of the longitudinal faces of the blocks 2. As a result, the only visible parts of a internal channel 5 are the series of sections of each of its turns, these sections being shown in dotted lines in FIGS. 2 and 3. FIG. 3 shows that each first internal channel 5 of a modular block 2 is connected to the first internal channel 5 of the adjacent adjacent block 2 by a bend 23 extending outside the blocks 2 along their lateral face 2a, the bends 23 being interconnected and forming a common water circulation circuit. There is provided a water inlet bend 23 and a water outlet bend and thus a water inlet circuit and a water outlet circuit. The input and output circuits can be separate or common.

When the input and output circuits are separated, the output bend is not visible in Figures 2 and 3 because lying behind the bend 23 associated and therefore hidden by it. As will be better seen in Figure 4 and as mentioned above, the second inner channel 5a of each block 2 may be disposed outside the first inner channel 5, which is not limiting. The second internal channels 5a of the modular blocks 2 are interconnected by input and output bends that can be separated or common. Each of these elbows is behind the elbow 23 of the first internal channel for each block and is therefore not visible in Figures 2 and 3. While considering that only are visible in Figures 2 and 3 the elbows 23 input of the first 5a channels, at least one series of inlet or outlet bends which externally connect, on the one hand, the first internal channels 5 between each other and, secondly, the second inner channels 5a therebetween comprise connectors allowing to easily connect and disconnect these internal channels 5, 5a with respect to the inputs and / or outputs of the associated water circuits.

FIG. 4 illustrates an embodiment of the path of the first internal channel 5 and the second internal channel 5a inside a modular block 2. This embodiment is not limiting and other modes of routing of the first and second internal channels 5, 5a in the block 2 are also possible.

In FIG. 4, the first and second internal channels 5, 5a advantageously consist of a respective tubing of folded metal embedded in the metal or alloy of the modular block 2. The tubing is preferably made of stainless steel. Advantageously, the tubing of one of the internal channels 5, 5a surrounds the tubing of the other of the internal channels 5a, 5.

It is advantageously the tubing of the second internal channel 5a forming part of the second internal circuit of the boiler connected to the hot water tank which surrounds the first internal channel 5 forming part of the first internal circuit of the boiler, but this can also be reversed. Advantageously, at least the tubing of one of the internal channels 5, 5a has rectangular or circular turns. In the embodiment shown in FIG. 4, a first tube associated with one of the internal channels 5, 5a, in this figure, without limitation the first internal channel 5, forms from an outermost turn 25a of the turns 25 narrowing towards the middle of the modular block 2 then turns 25 widening towards the outermost turn 25bis. The length of the turns 25, 25a thus increases from the center towards the periphery of the block 2, the outermost turn 25bis of the tubing having the greatest length. The second tube for the second internal channel 5a can at least partially surround the outermost turn 25bis, in Figure 4 that of the first tube associated with the first internal channel 5. To do this, the second tube has four sections in pairs perpendicular, these sections substantially along the inner periphery of the block 2 which is preferably square in Figure 4. The second pipe for the second inner channel 5a then forms a single rectangular coil 25a. Such a mode of arrangement of an internal channel 5 framed by the other internal channel 5a in a modular block 2, in FIG. 4 the first internal channel 5 inside the second internal channel 5a, accentuates the heating of the internal channel 5 box. This provides, in the case illustrated in FIG. 4, a stronger heating of the water for the heating installation passing through the first internal channel 5 of the blocks 2 of the boiler than for the water of the heating installation and storing water in a hot water tank, this water passing through the second internal channel 5a blocks 2 of the boiler.

Another possible mode of tubing for the first and second internal channels 5, 5a is to provide for each channel a tubulure having slots, the slots of a first tubing being inside the slots of the second tubing. Other modes of tubing are of course also possible, for example spiral tubing with the spirals of a tubular surrounding the spirals of the other tubing. Such embodiments provide substantially equivalent heating for both tubings. The first and second channels 5, 5a respectively have an inlet and a water outlet, all these inlets and outlets being, in the embodiment shown in FIG. 4, arranged on the same lateral side 2a of the modular block 2. This is therefore another embodiment of the inlets and outlets of the internal channels 5, 5a as shown in Figure 1 for which the inputs of the blocks were on a lateral side opposite to the lateral side carrying the outlets. With particular reference to FIG. 5 and also to FIGS. 2 and 3, the electric heating resistor 3 can be formed with a plate 26 of electrically insulating refractory material in which the electrical resistance itself is embedded. The plate 26 is advantageously incorporated towards the lower face 2c of each modular block 2 above said face 2c. The turns 25, 25a, 25a of the first and second internal channels 5, 5a extend above the plate 26 incorporating the heating resistor 3. This arrangement is favorable to the heat exchange between the resistor 3 and the internal channels 5, 5a of each block 2. The electric boiler that has just been described has the following main advantages. It provides an excellent thermal efficiency due to the optimal thermal contact between the modular blocks and the plate forming the heating resistor, by the optimal arrangement of the latter with respect to the first and second internal channels of water and the great length of the channels winding in their respective modular block. This thermal efficiency is improved because the electric boiler simultaneously heats two internal water circuits. The maximum power of the boiler can be adapted easily to the needs, by stacking on each other a more or less large number of modular blocks, for example five modular blocks. This can be done according to the needs of hot water or according to the season, the winter not guaranteeing an auxiliary heating for the buffer tank or the hot water tank as strong as during the summer and thus the power of the boiler in front to be increased during this season.

The heating control can be programmed in a cascade, for example by using three modules, ie 3 kW, which makes it possible to connect the boiler to a simple 220 V power outlet with 2.5 mm2 wires. This possibility makes the installation of the boiler according to the invention particularly simple and economical. 5 REFERENCES 1. Electric boiler 2. Modular block 2a, 2b. Side side 2c. Longitudinal face 3. Electrical resistance 4. Control box 5, 5a. First and second channels 6, 6a. First and second outlet pipes 7. Hot water tank 8. Buffer tank 9, 9a. Exhaust duct 10. Auxiliary heating source 11. Expansion vessel 12. Three-way valve 13. Fluid circuit 13a. Derivation 14, 14a. Exchanger 15, 15a. Circulator 16, 16a. First and second internal circuits 17. Thermostat 18. Water inlet 18a. Cold water inlet 20. Temperature probe 21, 21a. First and second outlets 22. Purge 23, 23a. Elbow 25, 25a. Spiers of the first and second channels 25a. Spire the outermost 26. Plate

Claims (16)

REVENDICATIONS1. Electric water circulating boiler (1) comprising a plurality of modular blocks (2) stacked on top of one another, each block (2) being traversed by a first internal water circulation channel (5), the first channel (5) ) of a block (2) being connected to the first channel (5) passing through an adjacent block (2) to form a first internal circuit (16) of water in the boiler (1), at least two modular blocks (2) each comprising an electric heating resistor (3) for heating the water of the first channel (5) passing therethrough, the electrical resistors (3) being individually connected to a regulation box (4) for switching on the circuit. a variable number of resistors (3) for adjusting the heating power, characterized in that each block (2) comprises a second internal water circulation channel (5a), the second channels (5a) being connected in series so forming a second internal circuit (16a) of water to the boiler (1), the second circuit (16a) being independent of the first circuit (16). 2. Boiler (1) electrical according to the preceding claim, wherein the first channel (5) of each block (2) comprises a first spiral pipe embedded in the material of said block (2) and the second channel (5a) of each block (2) comprises a second spiral tube embedded in the material of said block (2), one of the tubes surrounding the other tubing. 3. Boiler (1) electric according to the preceding claim, wherein a tubing of a first or second internal channel (5, 5a) forms, from an outermost turn (25a), turns (25) are narrowing towards the middle of the modular block (2) and then turns widening towards the outermost turn (25a), the tubing of the other second or first internal channel (5a, 5) at least partially surrounding the most outside (25bis). 4. An electric boiler according to any one of the preceding claims, wherein the first and second internal channels (5, 5a) of a block (2) are respectively connected to the first and second internal channels (5, 5a) of a block adjacent by an elbow (23, 23a), all of the first channels (5) of the blocks (2) and their associated elbows (23) forming the first internal circuit (16) while the set of second channels (5a ) blocks (2) and their associated bends (23a) forming the second internal circuit (16a), at least the elbows (23) associated with one of the internal circuits (16) having a connector for connecting and disconnecting each internal channel (5) the associated elbow (23). 5. Electric boiler (1) according to the preceding claim, wherein at least the elbows (23a) associated with one of the internal circuits (16a) are internal to two adjacent modular blocks (2). 6. Electric boiler (1) according to any one of the preceding claims, wherein each block (2) comprises a plate (26) of electrically insulating refractory material in which is embedded the electrical resistance (3), this plate (26). being incorporated in the lower face (2c) of said block (2), the first and second inner channels (5, 5a) of each block (2) extending above said plate (26) 7. Heating and water storage installation comprising a hot water tank (7) and at least one pre-heating source of the water contained in the tank (7), characterized in that the preheating source water is an electric boiler (1) according to any one of the preceding claims, the water inlet of the hot water tank (7) being connected to the second internal water circuit (16a) of the boiler (1) electric. 8. Installation according to the preceding claim, wherein the hot water tank (7) comprises inside a heat exchanger (14a) in which circulates a heat transfer fluid from a heating auxiliary source (10) external to the hot water tank (7), a coolant fluid circuit (13) connecting the auxiliary heating source (10) to the heat exchanger (14a), a circulator (15a) being provided in the fluid circuit (13). ) coolant. 9. Installation according to the preceding claim, wherein the auxiliary heating source (10) is a solar collector heating source. 10. Installation according to any one of the two preceding claims, wherein the coolant fluid circuit (13) passes through a buffer tank (8) filled with water, a heat exchanger (14) being provided in the buffer tank (8). ) for heating the water contained therein by the passage of the heat transfer fluid from the auxiliary heating source (10), the buffer tank (8) and the hot water tank (7) being arranged in series in the coolant fluid circuit (13). 11. Installation according to the preceding claim, wherein the heat transfer fluid circuit (13) comprises a bypass (13a), this bypass (13a) allowing the passage of the heat transfer fluid directly from the auxiliary heating source (10) to the balloon. hot water (7) without passing through the buffer tank (8), a three-way valve (12) being provided in the coolant fluid circuit (13). 12. Installation according to any one of the two preceding claims, wherein the buffer tank (8) rests on the upper face of a block (2) of the electric boiler (1), a heat transfer from the block (1) to the buffer tank (8). 13. Installation according to any one of the three preceding claims, wherein the water contained in the buffer tank (8) has been previously heated in the boiler (1) electric, the water inlet of the buffer tank (8) being connected to the first internal circuit (16) of water to the electric boiler (1). 14. Central heating installation having at least one radiator-type heating means in a central heating circuit for the circulation of heated water, characterized in that it comprises an installation according to one of claims 7 to 13. 15. central heating installation according to the preceding claim comprising an installation according to claim 13, the water outlet of the buffer tank (8) being connected to the central heating circuit. 16. central heating installation according to the preceding claim, wherein the buffer tank (8) comprises at least one temperature sensor (20), the temperature sensor (20) being connected to the control unit (4) of the boiler ( 1) and a second temperature sensor (20), the second temperature sensor (20) being connected to a thermostat (17) regulating the temperature in the central heating circuit.