EP4065901A1

EP4065901A1 - Device for producing hot liquid

Info

Publication number: EP4065901A1
Application number: EP20820512.0A
Authority: EP
Inventors: Nathalie BARENDRECHT; Aurélien SALLES
Original assignee: Commerciale Et D'engineering Ste
Current assignee: Commerciale Et D'engineering Ste
Priority date: 2019-11-29
Filing date: 2020-11-25
Publication date: 2022-10-05
Also published as: WO2021105611A1; CA3158097A1; US20230066658A1; US20220404065A1; EP4065907A1; CA3158093A1; WO2021105610A1

Abstract

Device (1) for producing hot liquid, comprising: - a tank (2) of liquid, - a system (6) for heating the contents of the tank (2), - a heat exchanger (7) comprising a primary circuit (8) equipped with a fluid inlet (8A) and a fluid outlet (8B), a secondary circuit (9) equipped with a fluid inlet (9A) and a fluid outlet (9B) and a region (10) for exchanging heat energy between the primary circuit (8) and the secondary circuit (9), - a circuit (11) for circulation in a loop between the tank (2) and the primary circuit (8) of the heat exchanger (7), and - a pump (12) arranged on the circuit (11) for circulation in a loop. The device (1) comprises a valve (31) arranged on the circuit (11) for circulation in a loop between the tank (2) and the primary circuit (8) of the heat exchanger (7), a member (32) for moving the valve (31) between an open position and a closed position, a control unit (17) for controlling at least the pump (12) and the member (32) for moving the valve (31).

Description

Title of the invention: Device for producing hot fluid

The present invention relates to a device for producing hot fluid, in particular domestic hot water.

[0002] It relates more particularly to a device for producing hot fluid comprising:

a liquid receiving tank equipped with at least one fluid inlet and one fluid outlet, at least the so-called inner part of the tank capable of being in contact with the filling liquid of the tank being made of synthetic material,

- a system for heating the contents of the tank,

- a heat exchanger comprising a primary circuit equipped with at least one fluid inlet and one fluid outlet, a secondary circuit fitted with at least one fluid inlet and one outlet and a heat exchange zone between the primary and secondary circuits located outside the tank,

- a loop circulation circuit between the tank and the primary circuit of the heat exchanger, and

- a pump arranged on the loop circulation circuit, the input of the secondary circuit of the heat exchanger being connectable to a source of fluid to be heated to allow the production of hot fluid at the outlet of the secondary circuit.

[0003] Such a device for producing hot fluid, in particular in the case of application to domestic hot water, is known. However, the design of current devices is not entirely satisfactory in terms of longevity, maintenance and efficiency of the device. In particular, the amount of hot water that can be produced is generally found to be low compared to the amount of water stored. Likewise, the control of the temperature of the fluid to be heated at the start of drawing is often imperfect.

An object of the invention is to provide a hot fluid production device whose design allows equal volume of the tank with a tank of a hot fluid production device of the state of the art. optimize the quantity of hot fluid produced in relation to the quantity of stored liquid in the tank without affecting the quality of the control of the temperature of the fluid to be heated at the start of drawing.

[0005] To this end, the invention relates to a device for producing hot fluid, in particular domestic hot water, comprising:

- a liquid receiving tank equipped with at least one fluid inlet and one fluid outlet, at least the so-called inner part of the tank capable of being in contact with the filling liquid of the tank being made of synthetic material

- a system for heating the contents of the tank,

- a pump arranged on the loop circulation circuit, the input of the secondary circuit of the heat exchanger being connectable at least to a source of fluid to be heated to allow the production of hot fluid at the output of the secondary circuit, characterized in that the device comprises a valve arranged on the loop circulation circuit between the tank and the primary circuit of the heat exchanger, a drive member in movement of the valve between an open position and a closed position, a unit control of at least the pump and the drive member in movement of the valve, the control unit being configured to control the actuation of the drive member in movement of the valve and therefore the passage of the valve from the open position to the closed position or vice versa depending on the on / off state of the pump.

The position of the heat exchange zone of the heat exchanger outside the tank frees up the useful space of the tank to store liquid therein and the realization of the part of the tank in contact with the liquid in terms of synthesis makes it possible to increase the heating temperature of said liquid, these two characteristics contributing to the optimization of the quantity of hot fluid produced relative to the quantity of liquid stored in the tank, without adversely affect the longevity of the device or its ease of maintenance. The design of the device can make it possible to dispense with a thermostatic mixing valve at the point of use of the hot fluid.

[0007] In addition, the presence of a controlled valve on the loop circulation circuit between the tank and the primary circuit of the heat exchanger makes it possible to perfectly control the thermosyphon phenomena.

According to one embodiment of the invention, the device comprises a clock and the control unit is configured to control the actuation of the drive member in displacement of the valve in the direction of an opening of the valve in parallel with the control of the start of the pump and configured to control the actuation of the drive member by moving the valve in the direction of a closing of the valve in the stopped state of the pump after stopping the pump for a predetermined period of time.

[0009] This particularly motorized controlled valve makes it possible to first authorize a thermosiphon and then to stop this phenomenon in order to keep the heat exchanger as cold as possible in order to make the temperature of the fluid to be heated more reliable at the start of the draw.

According to one embodiment of the invention, the pump is a variable flow pump and the device comprises means for regulating the flow rate of said pump, these means for regulating the flow rate of the pump comprising a flow meter arranged, from preferably, at the input of the secondary circuit, and at least two temperature probes, at least one of which is arranged on the circulation circuit in a loop between the tank and the primary circuit of the heat exchanger, and the control unit is configured to control the pump at least according to the data supplied by the temperature probes and the flowmeter.

The presence of an adjustable flow pump makes it possible to comply with the desired hot fluid temperature setpoint.

The regulation means make it possible to offer very good reactivity and instantaneous production of hot water at a temperature close to the desired set point temperature. Although the flowmeter can be in another location, the presence of the flowmeter at the inlet of the secondary circuit can be used to control the operation of the pump only when a flow is detected, which limits the wear of the pump and limits the energy consumption of the device.

According to one embodiment of the invention, the device comprises, at the input of the secondary circuit, in the connection zone of the input of the secondary circuit to at least one source of fluid to be heated, a duct arranged at least partially in the thickness of the tank, this so-called inlet duct which can be coupled at one end to the inlet of the secondary circuit of the heat exchanger dividing on the opposite end side of connection to at least one source of fluid to be heated in two branches one equipped with a shut-off member, the other with a flowmeter.

This arrangement makes it possible to supply the heat exchanger with cold fluid from the fluid network to be heated or with hot fluid from a hot fluid distribution network to allow immediate hot fluid output during withdrawal. .

According to one embodiment of the invention, the loop circulation circuit between the tank and the primary circuit of the heat exchanger comprises a forward branch arranged between the outlet of the tank and the inlet of the primary circuit and a return branch disposed between the outlet of the primary circuit and the inlet of the tank, the pump and the valve being preferably disposed on the outward branch of the loop circulation circuit.

[0016] According to one embodiment of the invention, the tank is equipped with an orifice for filling the tank with liquid, this filling orifice being connected by a fluidic connection which can be closed to the portion of the secondary circuit extending between the entry of the secondary circuit and the heat exchange zone between the primary and secondary circuits of the heat exchanger.

Preferably, the closable fluid connection is provided at the level of the filling orifice with a connection part to the tank, this connection part being provided with a vent, an overflow orifice and an additional orifice acting as an overflow or a vent depending on the filling level of the tank. This arrangement makes it possible to safely avoid a mixing of the "dead" water contained in the tank with the tank filling liquid from a network.

Preferably, the connection part to the tank fitted to the fluidic connection which can be closed at the level of the filling orifice is provided with a closure member movably mounted between a closed position and an open position and recalled under the effect of its own weight in closed position. Preferably, this closure member is a pivoting valve. The presence of such a closure member at this level makes it possible to prevent the formation of condensation at the level of the cover of the envelope.

According to one embodiment of the invention, the tank is equipped with a so-called lower level sensor and a so-called upper level sensor arranged at different heights in the tank, the closable fluid connection is provided with 'a shutter member equipped with an electric control circuit and the electric control circuit is configured to pass from the closed state corresponding to the open position of the shutter member to the open state corresponding to the position closed of the shutter member at least in the activated state of the higher level sensor. Thanks to this configuration, the risks of the tank overflowing are reduced.

According to one embodiment of the invention, the outlet of the tank connectable to the inlet of the primary circuit is arranged in the upper third of the interior volume of the tank and the inlet of the tank connectable to the outlet of the primary circuit is arranged in the lower third of the interior volume of the tank. Thanks to this arrangement of the inlet and outlet of the tank, the temperature stratification also called thermal stratification of the liquid inside the tank is maintained. This allows better control of the temperature of the liquid leaving the tank.

According to one embodiment of the invention, at least part of the heating system is housed in the tank and the inlet of the tank connectable to the outlet of the primary circuit of the heat exchanger opens into the tank at a level lower than the level occupied by the part of the heating system housed in the tank. Again, this arrangement makes it possible to maintain the temperature stratification of the liquid inside the tank. According to one embodiment of the invention, the tank comprises, in the lower half of the tank, on the outer surface of the tank, a reservation inside which the heat exchanger which is a heat exchanger countercurrent heat, preferably plate heat, is adapted to be accommodated to extend at least partially inside the overall jig of the vessel. This positioning of the heat exchanger in the lower part of the tank offers an advantage in terms of thermosyphon of the heat exchanger and in terms of maintaining the thermal stratification of the liquid contained in the tank.

In addition, this arrangement allows savings in terms of thermal insulation of the pipes of the various circuits.

According to one embodiment of the invention, the heat exchanger is, in the state connected to the tank, arranged at a level lower than the level occupied by the inlet of the tank which can be connected to the outlet of the circuit primary of said heat exchanger. This arrangement allows emptying by thermosiphon of the hot liquid that may be contained in the primary circuit of the heat exchanger, which makes it possible to better control the temperature of the fluid to be heated at the start of the draw. Indeed, it has been observed that if hot liquid stagnated in the primary circuit of the heat exchanger, it disturbed the control of the temperature of the fluid to be heated at the start of the draft. Finally, a portion of the hot liquid stagnant in the forward branch of the loop circuit between the tank and the heat exchanger can be reintroduced into the tank to be used during a next draw.

[0025] According to one embodiment of the invention, the tank comprises an enclosure, an enclosure at least partially surrounding the enclosure and an insulator disposed between the enclosure and the enclosure.

According to one embodiment of the invention, at least part of the heating system is housed in the tank and the thickness of the tank taken between the outer face of the casing and the inner face of the enclosure is in the part of the tank extending above the part of the heating system housed inside the tank at least locally greater than that of the thickness of the tank extending below the part of the heating system housed inside the tank. The reinforcement of the insulation in the upper part of the tank keeps the upper part of the tank as hot as possible. According to one embodiment of the invention, at least the heat exchanger, the pump, which has a variable flow rate, and the valve with its moving drive member, which is preferably a motor, form a set ready to assemble. This results in easier maintenance and manufacturing.

According to one embodiment of the invention, the heating system comprises at least one electrical resistance housed inside the tank, the tank comprises, at the level of the, or at least one of the electrical resistances, two facing openings, one in the enclosure, the other in the enclosure, these openings being connected by a casing body with a drilled bottom forming a connecting sleeve for said openings between them, this body housing extending at least partially inside the enclosure, and the electrical resistance is in the form of an elongated body provided with a seal threaded onto the electrical resistance, this seal in sealed bearing contact with the electric resistance sealingly closing the hole in the bottom of the housing body in the state through which said hole passes by the electric resistance.

Brief description of the drawings

The invention will be clearly understood on reading the following description of exemplary embodiments, with reference to the accompanying drawings in which:

[0030] [Fig. 1] is a schematic view of a device for producing domestic hot water in a configuration in which the pump is operating;

[0031] [Fig. 2] is a schematic view of a device for producing domestic hot water in a configuration in which the pump is not operating to illustrate the thermosiphon emptying of the heat exchanger;

[0032] [Fig. 3] shows a perspective view, in exploded position of the constituent elements, of a device for producing hot water;

[0033] [Fig. 4] shows an operating diagram of the hot water production device;

[0034] [Fig. 5] shows a partial perspective view of the lower part of the device in the removed state of the cover closing the compartment formed by a reservation made in the tank, this compartment serving to house the heat exchanger; [0035] [Fig. 6] shows a partial schematic view, partially in longitudinal section, of the device;

[0036] [Fig. 7] is a perspective view, in exploded position of the elements, of the connection means fitted to the cold part of the heat exchanger;

[0037] [Fig. 8] is a perspective view, in exploded position of the elements, of the connection means fitted to the hot part of the heat exchanger;

[0038] [Fig. 9] shows a sectional view of an electrical resistance in the state inserted in the tank; and

[0039] [Fig. 10] shows a perspective view, in exploded position of the elements, of an electrical resistance suitable for being inserted into the tank.

As mentioned above, the invention relates to a device 1 for producing fluid, in particular liquid, hot. In the example described below, the device 1 is a device for producing hot water, preferably sanitary, for instantaneous production of hot water, but such a device can be applied to the production of other types of water. hot liquids depending on the source of liquid to be heated retained without departing from the scope of the invention.

This hot liquid production device can be a domestic hot water production device suitable for installation in any type of construction.

The device 1 for producing hot water therefore comprises:

- a liquid receiving tank 2 equipped with at least one inlet 3 and one outlet 4 for fluid,

- a system 6 for heating the contents of the tank 2,

a heat exchanger 7 comprising a primary circuit 8 equipped with at least one inlet 8A and one fluid outlet 8B, a secondary circuit 9 equipped with at least one inlet 9A and one outlet 9B of fluid and a heat exchange zone 10 between primary 8 and secondary 9 circuits,

- a loop circulation circuit 11 between the tank 2 and the primary circuit 8 of the heat exchanger 7, and

- a pump 12 arranged on the loop circulation circuit 11, the inlet 9A of the secondary circuit 9 of the heat exchanger 7 being connectable to at least one source of domestic water to allow the production of domestic hot water at the outlet of the secondary circuit 9

- a valve 31 arranged on the circuit 11 for circulation in a loop between the tank 2 and the primary circuit 8 of the heat exchanger 7,

- a member 32, such as a motor, for driving the movement of the valve 31 between an open position and a closed position,

- And a control unit 17 at least of the pump 12 and of the drive member 32 in displacement of the valve 31. This control unit 17 is configured to control the actuation of the drive member 32 in displacement of the valve 31 in the direction of opening or closing of the valve 31 depending on the on / off state of the pump 12.

The liquid contained in the tank 2 is therefore heated to supply the primary circuit 8 of the heat exchanger before returning to the tank. The cold water from the building's sanitary water circuit, which is a pressurized water circuit, feeds the secondary circuit 9 of the heat exchanger 7.

This sanitary cold water is heated at the level of the heat exchanger 7 by exchanging calories with the primary circuit 8 of said exchanger before being distributed to any of the water points of the construction.

As a result of this operation, the liquid contained in the tank is said to be dead. Indeed, this liquid is not intended to be distributed but simply to heat the cold water of the sanitary water network.

In this device 1 for producing hot water, the liquid receiving tank 2, which may be water or an aqueous solution, or any other type of liquid is a tank with a vertical axis. In fact, this tank 2 has a face forming a bottom for supporting the ground and a top face, the longitudinal axis of the tank 2 passing through said faces. In the example shown, the tank is of generally parallelepipedal shape.

At least the so-called inner part of the tank 2 capable of being in contact with the filling liquid of the tank 2 is made of synthetic material, in particular of polyolefin such as polypropylene. This tank 2 stores the liquid under pressure atmospheric. At least one safety vent 36 which will be described in more detail below can be provided to prevent any overpressure inside the tank 2.

To avoid heat loss, the tank 2 comprises an enclosure 51, an envelope 52 at least partially surrounding the enclosure 51, and an insulator 53 disposed between the enclosure 51 and the envelope 52. The liquid is contained within inside the enclosure 51. The enclosure 51 is therefore equipped with the liquid inlet 3 and outlet 4 with the liquid outlet 4 disposed at a level higher than the level occupied by the liquid inlet 3 of tank. This enclosure 51 is made of synthetic material, preferably of polyolefin.

The envelope 52 is here formed of a body open on the top and a cover for closing the body. The enclosure 51 is thus inserted into the enclosure 52 which, in the closed state, completely surrounds the enclosure 51.

The insulation 53 is, for its part, formed by a foam, for example, injected into the casing in the inserted state of the enclosure in the casing 52 in the space left free between the outside of the enclosure 51 and the interior of the enclosure 52.

The tank 2 comprises, in the lower half of the tank 2, on the outer surface of the tank 2, a reservation 16 inside which the heat exchanger 7 is adapted to be housed to extend at least partially inside the overall jig of the tank 2. This reservation 16 is formed by a recess of said tank 2 formed in the side wall of the tank at the level of the zone of the side wall of the tank adjacent to the bottom of the tank. This reservation thus forms a housing for the heat exchanger outside the tank which can be closed by a cover. The heat exchanger 7 is thus placed outside the tank in the lower part of the tank 2, that is to say at the level of the lower half of the tank 2, near the bottom of the tank.

This heat exchanger 7 is, in the state connected to the tank 2, arranged at a level lower than the level occupied by the inlet 3 of the tank 2 which can be connected to the outlet 8B of the primary circuit 8 of said exchanger 7 of heat.

In the examples shown, the heat exchanger 7 is a countercurrent heat exchanger, in particular with plates, with the plates extending horizontally, that is to say substantially parallel to the face forming the bottom support on the floor of the tank. The inlets and outlets of the primary and secondary circuits of the heat exchanger are, in the example shown, provided on the same face of the block containing the plates of the exchanger 7.

To allow circulation in a loop between the tank 2 and the primary circuit 8 of the heat exchanger 7, the circuit 11 for loop circulation between the tank 2 and the primary circuit 8 of the heat exchanger 7 comprises an outward branch 11 A disposed between the outlet 4 of the tank 2 and the inlet 8A of the primary circuit 8 and a return branch 11 B disposed between the outlet 8B of the primary circuit 8 and the inlet 3 of the tank, the pump 12 and the valve 31 being here arranged on the outward branch 11 A of the loop circulation circuit 11, which constitutes a preferred solution although the pump 12 and the valve 31 can also be placed on the return branch.

The branch 11 A go is formed by a conduit, one end of which is permanently attached to the inlet 3 of the tank 2. This conduit has a length of conduit embedded in the insulation of the tank followed by a length of conduit which extends in the reservation 16 of the tank 2 to be connected to the inlet 8A of the primary circuit 8 of the heat exchanger 7.

The liquid circulates in the primary circuit 8 of the heat exchanger before leaving the heat exchanger at the outlet 8B of the heat exchanger. Again, a duct connects this outlet 8B of the heat exchanger to the inlet 3 of the enclosure of the tank and forms the return branch 11B of the circuit 11.

This connection between the inlet 3 of the tank and the outlet 8B of the primary circuit of the exchanger is of shorter length than the connection between the outlet 4 of the tank and the inlet 8A of the primary circuit 8 of the heat exchanger 7. Indeed, the outlet 4 of the tank connectable to the inlet 8A of the primary circuit 8 is arranged in the upper third of the internal volume of the tank 2 and the inlet of the tank 2 connectable to the outlet 8B of the primary circuit 8 is arranged in the lower third of the internal volume of the tank 2, it being understood that the upper third and the lower third are taken by reference to the total height of the internal volume of the vessel enclosure, this height being taken between the point on highest of internal volume and the lowest point of the internal volume in the position positioned on the ground of the tank resting by its face forming the bottom on a horizontal surface.

In practice, the enclosure of the vessel has a maximum filling level and the outlet of the vessel is generally disposed below this maximum filling level in the upper third of the vessel. Conversely, inlet 3 of tank 2 connectable to outlet 8B of primary circuit 8 of the heat exchanger opens into tank 2 at a level lower than the level occupied by part 6 of the heating system housed in the tank 2.

The aim is to extract liquid from the tank at the level of the hot zone of the tank and to reintroduce liquid into the tank at the level of the cold zone of the tank to avoid a disturbance of the thermal stratification which would cause turbulence generating a loss in volume of the volume of hot liquid that can be used.

The pump 12 which is used for this loop circulation of the liquid between the tank and the heat exchanger is a variable flow pump 12, such as a pump, with a "brushless" motor. The presence of the valve 31 and the adjustment of the flow rate of the pump make it possible to comply with the temperature setpoint of the domestic hot water to be distributed. This temperature setpoint is predefined.

In practice, the device 1 comprises a clock 171 whose data can be sent to the control unit 17. The control unit 17 is for its part configured to control the actuation of the drive member 32 in displacement of the valve 31, that is to say the drive motor in displacement of the valve 31, in the direction of opening of the valve 31 in parallel with the control of starting the pump 12. The control unit 17 is further configured to control the actuation of the drive member 32 in displacement of the valve. 31 in the direction of closing of the valve 31 as a function of the data supplied by the clock 171. In particular, the control unit 17 is still configured to control the actuation of the drive member 32 in displacement. of the valve 31 in the direction of closing the valve 31 in the stopped state of the pump 12 after stopping the pump 12 for a predetermined period of time. This predetermined period of time which may be fixed or variable is generally of the order of a few minutes.

To control the passage from the on state to the off state of the pump 12 or vice versa using the control unit 17, the device 1 comprises means 13 for regulating the flow rate of said pump 12 These means 13 for regulating the flow of the pump 12 comprise a flow meter 14 preferably arranged at the inlet of the secondary circuit 9, and at least two temperature probes 131 and 132, of which at least one, shown at 132 in the figures, is arranged. on the circulation circuit 11 in a loop between the tank 2 and the primary circuit 8 of the heat exchanger 7. The control unit 17 is configured to control the pump 12, and therefore, of course, the valve 31, at least according to the data supplied by the temperature probes 131 and 132. and the flowmeter 14. One of the temperature probes shown at 131 in the figures, is arranged at the input of the secondary circuit 9. Other temperature probes, such as a probe placed at the outlet of the secondary circuit 9, can also be provided.

The device 1 comprises, at the inlet of the secondary circuit 9 in the connection zone of the inlet 9A of the secondary circuit 9 to the domestic cold water network, a pipe 18 disposed at least partially in the thickness of the tank 2. In particular, this duct 18 is here partially embedded in the insulation 53 of the tank 2.

The end of the conduit 18 opposite to that connected to the inlet 9A of the secondary circuit 9 of the heat exchanger is divided into two branches, one connectable to the domestic cold water circuit and shown at 18B in the figures, the other, shown at 18A in the figures, connectable to a hot water circuit to allow immediate distribution of hot water at the outlet of the heat exchanger.

The branch 18B is equipped with the flowmeter 14 which forms one of the regulating means of the pump 12. The other branch 18A of the duct 18 is equipped with a closure member 20, such as a solenoid valve.

A temperature sensor 131 is arranged on the pipe 18, downstream of the connection zone of the branches 18A and 18B between them, between this zone of connection and input 9A of the secondary circuit of the heat exchanger.

This temperature sensor 131 forms the temperature sensor, placed at the input of the secondary circuit of the heat exchanger, and capable of helping to regulate the pump 12.

Likewise, the device 1 comprises at the outlet 9B of the secondary circuit 9, in the connection area of the outlet 9B of the secondary circuit to a hot water distribution network, a duct 19 disposed at least partially in the thickness of the tank 2. In particular, this duct 19 is here partially embedded in the insulation 53 of the tank 2.

A temperature probe can be placed on this duct 19.

The temperature probe 132 to aid in the regulation of the pump 12 arranged on the circuit 11 for circulation in a loop between the tank 2 and the primary circuit 8 of the heat exchanger 7 can be placed in the tank 2 as in the example shown or at the inlet of the primary circuit 8 on the duct forming the branch 11 A outward from the loop circuit between the tank 2 and the heat exchanger 7.

Finally, the device comprises, as mentioned above, a unit 17 for controlling at least the pump 12 and the valve 31, this control unit being configured to control the pump 12 and therefore the valve 31 to less as a function of the data supplied by the temperature probes 131, 132 and the flowmeter 14. The flow setpoint is given by the control unit for opening a water point of the construction.

This control unit 17 is in the form of an electronic and computer system which comprises, for example, a microprocessor and a working memory. According to a particular aspect, the control unit can have the form of a programmable logic controller. In other words, the functions and steps described can be implemented in the form of a computer program or via hardware components, for example programmable port networks, in particular, the functions and steps operated by the control unit or these modules can be produced by instruction and / or computer sets implemented in a process or controller or be produced by these dedicated electronic components or FPGA type components or ASIC. It is also possible to combine computer parts and electronic parts.

When it is specified that the unit or means or modules of said unit are configured to carry out a given operation, this means that the unit includes computer instructions and the corresponding execution means which make it possible to carry out said operation. operation and / or that the unit includes corresponding electronic components.

The regulation of the pump therefore uses at least the following input data:

- the domestic cold water inlet temperature in the heat exchanger,

- the water inlet temperature of the tank in the heat exchanger,

- the domestic hot water temperature setpoint, and

- the domestic water flow rate.

According to these data, the flow rate of the pump is chosen.

To allow the connection of the conduit 18 and the return branch 11 B of the circuit 11 in a loop to the heat exchanger, the heat exchanger comprises, at its cold part formed by the inlet 9A of the secondary circuit 9 and the outlet 8B of the primary circuit 8 arranged side by side on one face of the heat exchanger, a part 27 for connecting said inlet and outlet respectively to the duct 18 and to the return branch 11B.

This connecting piece 27, which comprises two sections of pipe for said connections, forms the support of a drain valve 25 capable of allowing emptying of the tank via the return branch 11B. This connecting part 27 further secures the fixing of the heat exchanger 7 on the tank 2 and the fixing of the temperature probes.

Similarly, the heat exchanger 7 comprises, at its hot part formed by the inlet 8A of the primary circuit and the outlet 9B of the secondary circuit arranged side by side on the same face of the heat exchanger, a part 26 for connecting said inlet and outlet respectively to the outgoing branch 11A of the loop circuit and to the duct 19. This connecting part 26, which comprises two sections of pipe for said connections, also forms a connection means for the pump 12. This connecting part also supports some of the temperature probes.

Thanks to this embodiment, at least the heat exchanger, the pump 12 which has a variable flow rate, the valve 31 and its displacement drive member 32 and the means 13 for regulating the flow of the pump 12 form a ready-to-assemble assembly.

To allow operation of the heat exchanger, it is necessary to heat the temperature of the tank to a temperature generally close to 70 ° C in the upper part of the tank, this temperature being able to be controlled using a temperature probe 28 positioned as close as possible to the heating system 6, for example in the housing body 23 presented below.

The heating system 6 can affect a large number of forms. In the example shown, the tank 2 comprises two electrical resistors, namely an upper electrical resistance and a lower electrical resistance, housed inside the tank, and a control unit for said electrical resistances.

The control unit is configured to selectively control said electrical resistors. This control unit is also configured to control the electric heaters at different temperature set points.

This control unit can be made common with the pump control unit 17 and is formed in the same way as that which has been described for the pump control unit of an electronic and computer system. which includes, for example, a microprocessor and a working memory.

The setpoint temperature of the lower electrical resistance is less than or equal to the setpoint temperature of the upper electrical resistance. The upper electrical resistance has priority. To allow simplified assembly of each electrical resistance, the tank

2 comprises, at the level of each of the electrical resistors, two opposite orifices 21, 22 formed one 21, in the enclosure 51, the other 22, in the casing 52, these orifices 21, 22 being connected by a housing body 23 with a drilled bottom 231 forming a connecting sleeve of said orifices 21, 22 between them. This housing body 23, made of synthetic material, is supported by its bottom on the enclosure 51, extending at least partially inside the enclosure 51. In particular, the hole in the bottom of the housing is bordered on the outside with a rim to form a tubular projection inserted into the orifice of the enclosure. The tubular protrusion of the housing body inserted into the orifice of the enclosure comprises two thermowells open towards the interior of the housing body, each thermowell being made integrally with the housing body. A temperature probe can be positioned inside one of the thermowells and a cut-off thermostat can be positioned inside the other of the thermowells. Each electrical resistance 61, 62 is in the form of an elongated body provided with a gasket 24 threaded onto the body of the resistance. This electrical resistance 61 or 62 is slidably introduced inside the housing body 23, passes through the bore 2311 in the bottom 231 of the housing body 23 to extend at least partially inside the tank 2. In particular , this electrical resistor 61 or 62 is positionable inside the housing body coaxially with the bore 2311 in the bottom of the housing body to project via said bore inside the enclosure, and is slidably movable to inside the housing body. In the positioned state of the electrical resistance 61 or 62 projecting at least partially inside the tank 2, and in the state through which the bore 2311 passes through the electrical resistance 61 or 62, the seal 24 in contact with sealed support with the resistance 61 or 62 sealingly closes the hole 2311 of the bottom 231 of the body 23 of the housing. A part 30 can also be slipped on the body of the resistance to come to cover the seal 24. This part 30 is fixed by screwing the body of the housing to prevent any untimely exit of the seal 24. This fastening part can therefore be slipped on the electrical resistance following the seal and is couplable by screwing to the housing body, this housing body comprising at least one screw hole made in one piece with said body.

The housing body 23 is closed by a cover 29 masking the resistance which can be removed from the tank by a simple pull exerted on the resistance electric. This cover is housed in a reinforcement of the casing provided at the orifice of the casing.

It is noted in the examples shown that the housing body comprises a bottom and a peripheral side wall and that the peripheral side wall of the housing body is provided with an outer peripheral flange disposed resting on the part of the internal surface of the casing surrounding the orifice of the casing.

[0089] As a variant, the tank can only comprise an electrical resistance.

Each resistor is a hairpin electrical resistor comprising a tubular body inside which is housed a resistive wire and at least one hot melt, the ends of the pin made in the form of two parallel branches each being provided with a electrical connector on which the gasket can be slipped.

In addition, the heating means can comprise a heat pump and a loop circulation circuit between the contents of the tank and the heat pump. The heating system may also comprise, in addition or as a variant, a solar collector 63 and means 64 for circulating the contents of the tank through said solar collector 63 as shown in FIG. 4. The heating system may also include a boiler, for example gas, connected to the tank.

Finally, to allow the tank to be filled in particular during the first use of the device for producing hot water, or in the event of evaporation of the liquid contained in the tank 2, the tank 2 is equipped, in its third upper, of an orifice 33 for filling the tank 2 with liquid. This filling orifice 33 is connected by a fluidic connection 35 which can be closed off to the portion of the secondary circuit 9 extending between the inlet 9A of the secondary circuit 9 and the heat exchange zone 10 between the primary 8 and secondary 9 circuits of the heat exchanger 2. This closable fluidic connection 35 is provided at the level of the filling orifice 33 with a part 34 for connection to the tank 2. This connection part 34 is provided with a vent 36, an orifice 37 for overflow. and an additional port 38 acting as an overflow or vent depending on the filling level of the tank 2. The additional port 38 is arranged at a higher level with respect to the overflow orifice 37. This additional orifice 38 is also placed at a lower level than that occupied by the vent 36. The configuration of this connection piece makes it possible to prevent any rising of “dead” water from the tank 2 into the distribution network. filling liquid during the tank filling operation.

This part 34 for connection to the tank 2 is also equipped with a closure member 43. This closure member 43 is, in the example shown, a pivoting valve mounted to pivot about a so-called horizontal axis extending perpendicularly to the longitudinal axis of the connection part 34 which is a tubular part. This closure member 43 is shaped and dimensioned to be returned to the closed position under the effect of its own weight. This normally closed closure member 43 is therefore able to switch from the closed position to the open position under the effect, for example, of a filling of the tank. The presence of such a closure member makes it possible to limit the appearance of condensation at the level of the cover 54 of the casing, in particular at the level of the part of the cover 54 shown at 44 in the figures which overlap at least partially. the connection piece 34.

To improve the safety of the installation and limit the risk of an untimely filling of the tank 2, the tank 2 is equipped with a so-called lower level sensor 39 and a so-called upper level sensor 40 arranged at different heights in the tank 2. In the examples shown, these sensors are floats axially offset along a rod inside the tank 2. The closable fluidic connection is provided with a member 41 of obturation, such as a solenoid valve. This closure member 41 is equipped with an electrical control circuit 42. The electrical control circuit 42 is configured to pass from the closed state corresponding to the open position of the shutter member 41 to the open state corresponding to the closed position of the shutter member 41 at least at the same time. 'activated state of the upper level sensor 40. Thus, when the filling level of the tank 2 reaches the upper level sensor 40, that is to say in the activated state of the upper level sensor 40, the latter ci acts as a switch of the electrical circuit 42 for controlling the shutter member 41 and switches the latter to open it. Thus, further filling of the vessel 2 from the fluidic connection is prevented. The device operates as follows:

When detecting a draw-off, this detection taking place using the flowmeter, temperature data measured by the various temperature probes placed at the inlet and / or outlet of the primary and secondary circuits as well as the measured flow rate values are sent to the control unit 17 which opens the valve 31 and regulates the flow rate of the pump 12 as a function of said data to allow heating of the domestic cold water to the predetermined set temperature.

At the end of the withdrawal, the pump 12 is stopped and the heat exchanger 7 is drained by thermosiphon to avoid any stagnation of hot water inside the heat exchanger. After a predetermined period of time, the valve 31 is closed to prevent any further flow of fluid. Indeed, outside of a domestic hot water draw, the pump is stopped. When the pump stops, the cold water contained in the bottom of the tank pushes the lukewarm water from the exchanger back into the tank via the outgoing branch of circuit 11 in a loop between the tank and the heat exchanger. heat until the level of separation between cold water and hot water at the level of cold water in the tank and in the water pipe of the outbound branch of the loop circuit is the same.

Thus, the lukewarm water from the exchanger is replaced by cold water from the bottom of the tank by a thermosiphon phenomenon.

This reverse circulation is shown in Figure 2. This reverse circulation is prevented once the valve 31 is closed, this closing of the valve 31 occurring a few minutes after stopping the pump 12, once the cooling of the. heat exchanger completed.

Claims

[Claim 1] Device (1) for producing hot fluid, in particular domestic hot water, comprising:

- a liquid receiving tank (2) equipped with at least one inlet (3) and one outlet (4) for fluid, at least the so-called inner part of the tank (2) capable of being in contact with the liquid for filling the tank (2) being in synthetic material,

- a system (6) for heating the contents of the tank (2),

- a heat exchanger (7) comprising a primary circuit (8) equipped with at least one inlet (8A) and one outlet (8B) for fluid, a secondary circuit (9) equipped with at least one inlet ( 9A) and a fluid outlet (9B) and a heat exchange zone (10) between the primary (8) and secondary (9) circuits arranged outside the tank (2),

- a loop circulation circuit (11) between the tank (2) and the primary circuit (8) of the heat exchanger (7), and

- a pump (12) arranged on the loop circulation circuit (11), the input (9A) of the secondary circuit (9) of the heat exchanger (7) being connectable at least to one source of fluid to be heated to allow the production of hot fluid at the outlet of the secondary circuit (9), characterized in that the device (1) comprises a valve (31) arranged on the circuit (11) for circulation in a loop between the tank (2) and the primary circuit (8) of the heat exchanger (7), a member (32) for driving the movement of the valve (31) between an open position and a closed position, a unit (17) for controlling at least the pump (12) and the drive member (32) in displacement of the valve (31), the control unit (17) being configured to control the actuation of the drive member (32) in displacement of the valve (31) and consequently the passage of the valve (31) from the open position to the closed position or vice versa depending on the on / off state of the pump (12).

[Claim 2] Device (1) according to claim 1, characterized in that the device (1) comprises a clock (171) and in that the control unit (17) is configured to control the actuation of the member (32) for driving the movement of the valve (31) in the direction of a opening of the valve (31) in parallel with the command to start the pump (12) and configured to control the actuation of the drive member (32) by moving the valve (31) in the direction of a closing of the valve (31) in the stopped state of the pump (12) after stopping the pump (12) for a predetermined period of time.

[Claim 3] Device (1) according to one of claims 1 or 2, characterized in that the pump (12) is a variable flow pump and in that the device (1) comprises means (13) for regulating of the flow rate of said pump (12), these means (13) for regulating the flow rate of the pump (12) comprising a flow meter (14) preferably arranged at the inlet of the secondary circuit (9), and at least two probes ( 131, 132) of which at least one is arranged on the circuit (11) for circulation in a loop between the tank (2) and the primary circuit (8) of the heat exchanger (7), and in that the The control unit (17) is configured to control the pump (12) at least according to the data provided by the temperature probes (131, 132) and the flow meter (14).

[Claim 4] Device (1) according to claim 3, characterized in that the device (1) comprises, at the input of the secondary circuit (9), in the connection zone of the input (9A) of the circuit (9) secondary to at least one source of fluid to be heated, a conduit (18) disposed at least partially in the thickness of the tank (2), this conduit (18) called the inlet which can be coupled at one end to the inlet (9A ) of the secondary circuit (9) of the heat exchanger (2) dividing on the opposite end side of connection to at least one source of fluid to be heated into two branches (18A, 18B) equipped one (18A), with one closure member (20), the other (18B), of the flowmeter (14).

[Claim 5] Device (1) according to one of claims 1 to 4, characterized in that the circuit (11) for circulating in a loop between the tank (2) and the circuit (8) primary of the exchanger (7 ) of heat comprises a branch (11 A) go disposed between the outlet (4) of the tank (2) and the inlet (8A) of the primary circuit (8) and a branch (11 B) return disposed between the outlet ( 8B) of the primary circuit (8) and the inlet (3) of the tank (2), the pump (12) and the valve (31) being preferably arranged on the branch (11 A) of the outgoing circuit ( 11) loop circulation.

[Claim 6] Device (1) according to one of claims 1 to 5, characterized in that the tank (2) is equipped with an orifice (33) for filling the tank (2) with liquid, this orifice ( 33) filling being connected by a fluidic connection (35) which can be closed to the portion of the secondary circuit (9) extending between the inlet (9A) of the secondary circuit (9) and the heat exchange zone (10) between the primary (8) and secondary (9) circuits of the heat exchanger (2).

[Claim 7] Device (1) according to claim 6, characterized in that the closable fluid connection (35) is provided at the level of the orifice (33) for filling a part (34) for connection to the tank ( 2), this connection piece (34) being provided with a vent (36), an orifice (37) for overflow and an orifice (38) acting as an overflow or a vent depending on the filling level of the tank (2).

[Claim 8] Device (1) according to one of claims 6 or 7, characterized in that the tank (2) is equipped with a said lower level sensor (39) and a said upper level sensor ( 40) arranged at different heights in the tank (2), in that the closable fluid connection (35) is provided with a closure member (41) equipped with an electrical control circuit (42) and in this that the electrical control circuit (42) is configured to pass from the closed state corresponding to the open position of the shutter member (41) to the open state corresponding to the closed position of the member (41) shutter at least in the activated state of the upper level sensor (40).

[Claim 9] Device (1) according to one of claims 1 to 8, characterized in that the outlet (4) of the tank (2) connectable to the inlet (8A) of the primary circuit (8) is arranged in the upper third of the internal volume of the tank (2) and the inlet of the tank (2) which can be connected to the outlet (8A) of the primary circuit (8) is placed in the lower third of the internal volume of the tank (2) , in that at least part of the heating system (6) is housed in the tank (2) and in that the inlet (3) of the tank (2) can be connected to the outlet (8B) of the circuit ( 8) the primary heat exchanger (2) opens into the tank (2) at a level lower than the level occupied by the part of the heating system (6) housed in the tank (2).

[Claim 10] Device (1) according to one of claims 1 to 9, characterized in that the tank (2) comprises, in the lower half of the tank (2), on the outer surface of the tank (2) a reservation (16) inside which the heat exchanger (7) which is a countercurrent exchanger (7), preferably with plates, is adapted to be housed to extend at least partially to the 'inside the overall jig of the tank (2).

[Claim 11] Device (1) according to one of claims 1 to 10, characterized in that the heat exchanger (7) is, in the state connected to the tank (2), arranged at a level below the level occupied by the inlet of the tank (2) which can be connected to the outlet (8B) of the primary circuit (8) of said heat exchanger (7).

[Claim 12] Device (1) according to one of claims 1 to 11, characterized in that the vessel (2) comprises an enclosure (51), an envelope (52) at least partially surrounding the enclosure (51) and an insulator (53) disposed between the enclosure (51) and the casing (52).

[Claim 13] Device (1) according to claim 12, characterized in that at least part of the heating system (6) is housed in the tank (2) and in that the thickness of the tank (2) engaged between the outer face of the casing (52) and the inner face of the enclosure (51) is in the part of the vessel (2) extending above the part of the heating system (6) housed inside the tank (2) at least locally greater than that of the thickness of the tank extending below the part of the heating system (6) housed inside the tank (2) .

[Claim 14] Device (1) according to one of claims 1 to 13, characterized in that at least the heat exchanger (7), the pump (12) which has a variable flow rate and the valve (31) with its displacement drive member (32) which is preferably a motor, form a ready-to-assemble assembly.

[Claim 15] Device (1) according to one of claims 1 to 14, taken in combination with one of claims 12 or 13, characterized in that the heating system (6) comprises at least one resistor (61, 62) electrical housed inside the tank (2), in that the tank (2) comprises, at the level of the, or at least one of the electric resistances (61, 62), two orifices ( 21, 22) opposite provided one (21), in the enclosure (51), the other (22), in the casing (52), these orifices (21, 22) being connected by a housing body (23) with a drilled bottom (231) forming a connecting sleeve for said orifices (21, 22) between them, this housing body (23) extending at least partially inside the enclosure (51), and in that the electrical resistor (61, 62) is in the form of an elongated body provided a seal (24) threaded onto the electrical resistance (61, 62), this seal (24) in sealed contact contact with the electrical resistance (61, 62) sealingly closing the bore (2311) in the base ( 231) of the housing body (23) in the state through which said bore (2311) passes by the electrical resistance (61, 62).