FR3103886A1 - Hot fluid production device - Google Patents

Abstract

Device (1) for producing hot fluid comprising: - a liquid tank (2), - a system (6) for heating the contents of the tank (2), - a heat exchanger (7) comprising a circuit (8) ) primary fitted with a fluid inlet (8A) and outlet (8B), a secondary circuit (9) fitted with a fluid inlet (9A) and outlet (9B) and a zone (10 ) heat exchange between the 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) heat, and - a pump (12) arranged on the loop circulation circuit (11). The device (1) comprises a valve (31) arranged on the loop circulation circuit (11) 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, at least one control unit (17) of the pump (12) and the drive member (32) in displacement of the valve (31) .Figure for the summary: Fig. 1

Description

Device for producing hot fluid

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

It relates more particularly to a hot fluid production device 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 liquid filling the tank being made of synthetic material,
- a heating system for the contents of the tank,
- a heat exchanger comprising a primary circuit equipped with at least one fluid inlet and one outlet, a secondary circuit equipped with at least one fluid inlet and one outlet and a calorie exchange zone between the primary and secondary circuits arranged outside the tank,
- a circulation circuit in a loop between the tank and the primary circuit of the heat exchanger, and
- A pump arranged on the circulation loop circuit, the inlet 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.

Such a device for producing hot fluid, in particular in the case of an application to domestic hot water, is known. However, the design of current devices does not give complete satisfaction in terms of longevity, maintenance and performance of the device. In particular, the quantity of hot water that can be produced is generally found to be low compared to the quantity of water stored. Similarly, the control of the temperature of the fluid to be heated at the start of the draw 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 to optimize the quantity of hot fluid produced in relation to the quantity of liquid stored in the tank without affecting the quality of control of the temperature of the fluid to be heated at the start of the draw.

To this end, the subject of the invention is 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 heating system for the contents of the tank,
- a heat exchanger comprising a primary circuit equipped with at least one fluid inlet and one outlet, a secondary circuit equipped with at least one fluid inlet and one outlet and a calorie exchange zone between the primary and secondary circuits arranged outside the tank,
- a circulation circuit in a loop between the tank and the primary circuit of the heat exchanger, and
- a pump arranged on the circulation circuit in a loop, the inlet of the secondary circuit of the heat exchanger being connectable to at least one source of fluid to be heated to allow the production of hot fluid at the outlet of the secondary circuit,
characterized in that the device comprises a valve arranged on the circulation circuit in a loop between the tank and the primary circuit of the heat exchanger, a drive member for moving the valve between an open position and a closed position, a unit for controlling at least the pump and the drive member in displacement of the valve, the control unit being configured to control the actuation of the drive member in displacement of the valve and consequently 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 calorie exchange zone of the heat exchanger outside the tank makes it possible to free up the useful space of the tank to store liquid therein and to make the part of the tank in contact with the synthetic material liquid 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 in relation to the quantity of liquid stored in the tank, without harming 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.

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 thermosiphon 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 command to start the pump and configured to command the actuation of the driving member in displacement of the valve in the direction of closing the valve in the stopped state of the pump after stopping the pump for a predetermined period of time.

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

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 preferably arranged in inlet of the secondary circuit, and at least two temperature sensors, at least one of which is arranged on the circulation circuit in a loop between the vessel and the primary circuit of the heat exchanger, and the control unit is configured to control the pump at least according to the data provided by the temperature sensors and the flowmeter.

The presence of an adjustable flow pump makes it possible to respect the desired hot fluid temperature set point.

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

According to one embodiment of the invention, the device comprises, at the inlet of the secondary circuit, in the connection zone of the inlet of the secondary circuit to at least one source of fluid to be heated, a conduit disposed at least partially in the thickness of the tank, this so-called inlet duct which is coupleable at one end to the inlet of the secondary circuit of the heat exchanger, dividing on the opposite end side for connection to at least one source of fluid to be heated into two branches equipped with the 'one, a shutter member, the other, a flow meter.

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 outlet during withdrawal.

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

According to one embodiment of the invention, the tank is equipped with a liquid filling orifice of the tank, this filling orifice being connected by a closable fluid connection to the secondary circuit portion extending between the inlet of the secondary circuit and the calorie 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 piece to the tank, this connection piece being provided with a vent, an overflow orifice and a additional orifice acting as overflow or vent depending on the level of filling of the tank. This arrangement makes it possible to reliably avoid a mixing of the "dead" water contained in the tank with the liquid filling the tank from a network.

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 fluidic connection is provided with a member shutter equipped with an electrical control circuit and the electrical 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 closed position of the shutter member at least in the activated state of the upper 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 placed in the lower third of the interior volume of the tank. Thanks to this arrangement of the inlets and outlets 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 against -current, preferably plates, is adapted to be housed to extend at least partially inside the overall template of the tank. This positioning of the heat exchanger in the lower part of the tank offers an advantage in terms of thermosiphoning 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 connectable to the outlet of the primary circuit of said exchanger heat. 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 was found 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 draw. Finally, part of the hot stagnant liquid in the outward leg of the loop circuit between vessel and heat exchanger can be reintroduced into the vessel to be used during a subsequent draw.

According to one embodiment of the invention, the tank comprises an enclosure, an envelope at least partially surrounding the enclosure and an insulator placed between the enclosure and the envelope.

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 external face of the casing and the internal 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 heating 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 an assembly ready to rise. This results in easier maintenance and manufacturing.

According to one embodiment of the invention, the heating system comprises at least one electric resistance housed inside the tank, the tank comprises, at the level of, or at least one of the electric resistances, two facing orifices, one formed in the enclosure, the other in the casing, these orifices being connected by a housing body with a pierced bottom forming a sheath for connecting said orifices to each other, this housing body s extending at least partially inside the enclosure, and the electrical resistor is in the form of an elongated body provided with a seal threaded over the electrical resistor, this seal in sealing bearing contact with the electrical resistor sealingly closing the hole in the bottom of the housing body in the state through which said hole is crossed by the electrical resistance.

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

shows a schematic view of a device for producing domestic hot water in a configuration in which the pump operates;

represents a schematic view of a device for producing domestic hot water in a configuration in which the pump is not operating to illustrate the emptying by thermosiphon of the heat exchanger;

shows a perspective view, in exploded position of the constituent elements, of a device for producing hot water;

shows an operating diagram of the hot water production device;

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;

shows a partial schematic view, partially in longitudinal section, of the device;

shows a perspective view, in exploded position of the elements, of the connection means equipping the cold part of the heat exchanger;

shows a perspective view, in exploded position of the elements, of the connection means equipping the hot part of the heat exchanger;

shows a sectional view of an electrical resistor in the state inserted into the tank; And

shows a perspective view, in exploded position of the elements, of an electrical resistor capable of being inserted into the tank.

As mentioned above, the subject of the invention is a device 1 for producing hot fluid, in particular liquid. In the example described below, 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 hot liquids depending on the source of liquid to be heated selected 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 tank 2 for receiving liquid 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 an outlet 8B of fluid, a secondary circuit 9 equipped with at least one inlet 9A and one outlet 9B of fluid and a heat exchange zone 10 between the primary 8 and secondary 9 circuits,
- a circulation circuit 11 in a loop 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 in secondary circuit output 9
- a valve 31 arranged on the circulation circuit 11 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 valve 31 in displacement between an open position and a closed position,
- and a unit 17 for controlling at least the pump 12 and the member 32 for driving the valve 31 in displacement. This control unit 17 being configured to control the actuation of the member 32 for driving in displacement of valve 31 in the direction of opening or closing of valve 31 depending on the on/off state of pump 12.

The liquid contained in 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 sanitary water circuit of the construction, which is a pressurized water circuit, supplies the secondary circuit 9 of the heat exchanger 7 .

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

Because 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 tank 2 for receiving liquid, which can be water or an aqueous solution, or any other type of liquid, is a tank with a vertical axis. Indeed, this tank 2 has a face forming the bottom to support the ground and a top face, the longitudinal axis of the tank 2 passing through said faces. In the example shown, the tank is generally parallelepipedic in shape.

At least the so-called inner part of the tank 2 capable of being in contact with the liquid filling the tank 2 is made of synthetic material, in particular of polyolefin such as polypropylene. This tank 2 stores the liquid at atmospheric pressure. 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 inside of the enclosure 51. The enclosure 51 is therefore equipped with the inlet 3 and the outlet 4 of liquid with the outlet 4 of liquid arranged at a level higher than the level occupied by the inlet 3 of the liquid of the tank. This speaker 51 is made of synthetic material, preferably polyolefin.

The casing 52 is here formed of a body open on the top and of a cover for closing the body. The enclosure 51 is thus inserted into the envelope 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 envelope in the inserted state of the enclosure in the envelope 52 in the space left free between the outside of the enclosure 51 and the inside of the envelope 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 template of the tank 2. This reservation 16 is formed by a recess of the said tank 2 formed in the side wall of the tank at the level of the zone of the side wall of the tank adjoining the bottom of the tank. This reservation thus forms a housing for the heat exchanger outside the vessel which can be closed by a cover. The heat exchanger 7 is thus arranged 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 connectable to the outlet 8B of the primary circuit 8 of said heat exchanger 7 .

In the examples shown, the heat exchanger 7 is a countercurrent exchanger, in particular a plate exchanger, with the plates extending horizontally, that is to say substantially parallel to the face forming the support bottom. on the floor of the tank.

The inputs and outputs 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 loop circulation circuit 11 between the tank 2 and the primary circuit 8 of the heat exchanger 7 comprises a branch 11A go arranged between the outlet 4 of the tank 2 and the inlet 8A of the primary circuit 8 and a return branch 11B arranged 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 outgoing branch 11A of the loop circulation circuit 11, which constitutes a preferred solution although the pump 12 and the valve 31 can also be arranged on the return branch.

The outgoing branch 11A 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 input 8A of the primary circuit 8 of the heat exchanger 7.

The liquid circulates in the primary circuit 8 of the heat exchanger before emerging from the heat exchanger at the level of the outlet 8B of the heat exchanger. Again, a conduit connects this output 8B of the heat exchanger to the input 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 exchanger 7 of heat. Indeed, the output 4 of the tank connectable to the input 8A of the primary circuit 8 is arranged in the upper third of the interior volume of the tank 2 and the input of the tank 2 connectable to the output 8B of the primary circuit 8 is disposed in the lower third of the interior volume of the vessel 2, it being understood that the upper third and the lower third are taken with reference to the total height of the interior volume of the enclosure of the vessel, this height being taken between the point highest of the interior volume and the lowest point of the interior volume in the state positioned on the ground of the tank resting by its face forming the bottom on a horizontal surface.

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

The pump 12 which is used for this loop circulation of the liquid between tank and heat exchanger is a pump 12 with variable flow, 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 respect the temperature set point for 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 itself 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 an opening of the valve 31 in parallel with the control of the start of the pump 12. The control unit 17 is further configured to control the actuation of the drive member 32 in movement of the valve 31 in the direction of a closing of the valve 31 according to 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 can be fixed or variable, is generally of the order of a few minutes.

To control the transition 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 input of the secondary circuit 9, and at least two temperature probes 131 and 132, at least one of which, shown at 132 in the figures, is arranged on the circuit 11 circulation 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 provided by the temperature sensors 131 and 132. and the flow meter 14. One of the temperature sensors shown at 131 in the figures, is arranged at the input of the secondary circuit 9. Other temperature sensors such as a sensor disposed at the output 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 sanitary cold water network, a conduit 18 arranged at least partially in the thickness of the tank 2. particular, this pipe 18 is here partially embedded in the insulation 53 of the tank 2.

The end of conduit 18 opposite that connected to inlet 9A of secondary circuit 9 of the heat exchanger is divided into two branches, one of which can be connected to the domestic cold water circuit and shown at 18B in the figures, the other, shown at 18A in the figures, can be connected 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 means for regulating the pump 12. The other branch 18A of the conduit 18 is equipped with a closure member 20, such as a solenoid valve.

A temperature sensor 131 is placed on the pipe 18, downstream of the connection zone of the branches 18A and 18B between them, between this connection zone and the inlet 9A of the secondary circuit of the heat exchanger. This temperature sensor 131 forms the temperature sensor, placed at the inlet of the secondary circuit of the heat exchanger, and capable of helping to regulate the pump 12.

In the same way, the device 1 comprises at the output 9B of the secondary circuit 9, in the connection zone of the output 9B of the secondary circuit to a hot water distribution network, a conduit 19 arranged at least partially in the thickness of the tank 2. In particular, this conduit 19 is here partially embedded in the insulation 53 of the tank 2.

A temperature sensor can be placed on this conduit 19.

The temperature sensor 132 for assisting in the regulation of the pump 12 placed on the circulation circuit 11 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 input of the primary circuit 8 on the conduit forming the branch 11A to go 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 consequently the valve 31 at least in function data provided by the temperature sensors 131, 132 and the flow meter 14. The flow setpoint is given by the opening control member of 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 take the form of a programmable automaton. In other words, the functions and steps described can be implemented in the form of a computer program or via hardware components, for example networks of programmable ports, 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 components of the FPGA or ASIC type. 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 comprises computer instructions and the corresponding means of execution which make it possible to carry out said operation and/ or that the unit includes corresponding electronic components.

The pump control 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 sanitary water flow.

Depending on these data, the flow rate of the pump is chosen.

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

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

In the same way, 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 heat, a part 26 for connecting said input and output respectively to the forward branch 11A of the loop circuit and to the conduit 19.

This connecting part 26, which comprises two pipe sections for said connections, also forms a connection means for the pump 12. This connecting part also supports some of the temperature sensors.

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

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 probe. 28 temperature positioned closer to the heating system 6, for example in the body 23 of the housing presented below.

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

The control unit is configured to selectively control said electrical resistors. This control unit is also configured to control the electrical resistors at different temperature setpoints.

This control unit can be made common with the pump control unit 17 and is formed in the same way as what has been described for the pump control unit of an electronic and computer system which comprises, 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 a simplified assembly of each electric resistance, the tank 2 comprises, at the level of each of the electric resistances, two facing 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 pierced bottom 231 forming a connecting sheath of said orifices 21, 22 between them. This casing 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 casing is bordered on the outside with a flange to form a tubular projection inserted into the opening of the enclosure. The tubular projection of the casing body inserted into the orifice of the enclosure comprises two thimbles open towards the inside of the casing body, each thimble being made in one piece with the casing body. A temperature probe can be positioned inside one of the thimbles and a cut-off thermostat can be positioned inside the other of the thimbles. Each electrical resistor 61, 62 is in the form of an elongated body provided with a joint 24 threaded onto the body of the resistor. This electrical resistance 61 or 62 is introduced by sliding inside the body 23 of the casing, passes through the bore 2311 of the bottom 231 of the body 23 of the casing to extend at least partially inside the tank 2. In particular , this electrical resistor 61 or 62 is positionable inside the case body coaxially with the hole 2311 of the bottom of the case body to protrude through said hole inside the enclosure, and is movable by sliding at inside the housing body. In the positioned state of the electrical resistor 61 or 62 projecting at least partially inside the tank 2, and in the state traversed by the bore 2311 by the electrical resistor 61 or 62, the seal 24 in contact with Sealed support with resistance 61 or 62 closes in a sealed manner the bore 2311 of the bottom 231 of the body 23 of the case. A piece 30 can also be slipped onto the body of the resistor to overlap the seal 24. This piece 30 is fixed by screwing the body of the housing to prevent any untimely exit of the seal 24. This fixing piece can therefore be slipped on the electrical resistance following the seal and is coupleable by screwing to the housing body, this housing body comprising at least one screw channel made in one piece with said body.

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

It is noted in the examples shown that the box body comprises a bottom and a peripheral side wall and that the peripheral side wall of the body of the box is provided with an external peripheral collar placed in abutment on the part of the internal surface of the shroud surrounding the shroud orifice.

As a variant, the tank can comprise only 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 hairpin made in the form of two parallel branches each being provided with an electrical connector on which the gasket is suitable for slipping on.

In addition, the heating means may comprise a heat pump and a loop circulation circuit between the contents of the tank and the heat pump. The heating system may further 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 further comprise a boiler, for example gas, connected to the tank.

Finally, to allow the filling of the tank, in particular during the first use of the hot water production device, or in the event of evaporation of the liquid contained in the tank 2, the tank 2 is equipped, in its upper third, with an orifice 33 for filling the tank with liquid .2. This filling orifice 33 is connected by a closable fluidic connection 35 to the secondary circuit portion 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 sealable fluidic connection 35 is provided at the level of the filling orifice 33 with a part 34 for connection to the tank 2. This part 34 for connection is provided with a vent 36, an orifice 37 for overflow and an additional orifice 38 acting as an overflow or a vent depending on the filling level of the tank 2. The additional orifice 38 is arranged at a higher level with respect to the orifice 37 of overflow . This additional orifice 38 is moreover arranged at a lower level than that occupied by the vent 36. The configuration of this connecting piece makes it possible to avoid any rise of the "dead" water from the tank 2 into the distribution network. filling liquid during the tank filling operation.

To improve the safety of the installation and limit the risk of 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 heights different in the tank 2. In the examples shown, these sensors are floats offset axially along a rod inside the tank 2. The sealable fluid connection 35 is provided with a closure member 41, such as than a solenoid valve. This shutter 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 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, it it acts as a switch of the electrical circuit 42 for controlling the shutter member 41 and switches the latter to open it. Thus, a continuation of the filling of the tank 2 from the fluid connection is prevented.

The device works as follows:

When a withdrawal is detected, this detection being carried out using the flow meter, the temperature data measured by the various temperature probes arranged at the input and/or output of the primary and secondary circuits as well as the flow value measured are sent to the control unit 17 which opens the valve 31 and regulates the flow rate of the pump 12 according to 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 circulation of fluid. In fact, apart from drawing domestic hot water, the pump is stopped. When the pump stops, the cold water contained in the bottom of the tank pushes the warm water from the exchanger back into the tank via the forward branch of circuit 11 in a loop between the tank and the heat exchanger. heat until the level of separation between cold and hot water at the level of the cold water in the tank and in the water pipe of the outward branch of the loop circuit is the same.

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

This reverse circulation is represented in FIG. 2. This reverse circulation is prevented once the valve 31 is closed, this closing of the valve 31 taking place a few minutes after the stoppage of the pump 12, once the cooling of the heat exchanger completed.

Claims (15)

Device (1) for producing hot fluid, in particular domestic hot water, comprising:
- a tank (2) for receiving liquid equipped with at least one fluid inlet (3) and one outlet (4), at least the so-called inner part of the tank (2) capable of being in contact with the liquid filling the tank (2) being made of 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 fluid inlet (8A) and an outlet (8B), a secondary circuit (9) equipped with at least one inlet ( 9A) and a fluid outlet (9B) and a calorie 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 inlet (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 circulation circuit (11) in a loop between the tank (2) and the primary circuit (8) of the heat exchanger (7), a member (32) for driving the valve (31) in displacement between an open position and a closed position, a unit (17) for controlling at least the pump (12) and the member (32) for driving movement of the valve (31), the control unit (17) being configured to control the actuation of the member (32) for driving the movement 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). 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) displacement drive of the valve (31) in the direction of an opening of the valve (31) in parallel with the command to start the pump (12) and configured to command the actuation of the member (32 ) driving 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 . 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 the flow 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 input of the secondary circuit (9), and at least two probes (131, 132) temperature, at least one of which is arranged on the circulation circuit (11) in a loop between the tank (2) and the primary circuit (8) of the heat exchanger (7), and in that the unit (17 ) control is configured to control the pump (12) at least according to the data provided by the temperature sensors (131, 132) and the flow meter (14). 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 secondary circuit (9) to at least a source of fluid to be heated, a pipe (18) arranged at least partially in the thickness of the tank (2), this pipe (18) said to be coupling inlet at one end to the inlet (9A) of the circuit ( 9) secondary of the heat exchanger (2) dividing on the opposite end side for connection to at least one source of fluid to be heated into two branches (18A, 18B) one equipped (18A), with a member (20 ) shutter, the other (18B), the flow meter (14). Device (1) according to one of Claims 1 to 4, characterized in that the circulation circuit (11) in a loop between the tank (2) and the primary circuit (8) of the heat exchanger (7) comprises a branch (11A) to go arranged between the outlet (4) of the tank (2) and the inlet (8A) of the primary circuit (8) and a branch (11B) return arranged between the outlet (8B) of the circuit (8 ) primary and the inlet (3) of the tank (2), the pump (12) and the valve (31) being arranged, preferably, on the branch (11A) go of the circuit (11) circulation loop. 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) for filling being connected by a closable fluid connection (35) to the portion of the secondary circuit (9) extending between the inlet (9A) of the secondary circuit (9) and the zone (10) for heat exchange between the primary circuits (8) and secondary (9) of the heat exchanger (2). Device (1) according to claim 6, characterized in that the sealable fluid connection (35) is provided at the level of the filling orifice (33) with a part (34) for connection to the tank (2), this connecting piece (34) provided with a vent (36), an overflow orifice (37) and an additional orifice (38) acting as an overflow or a vent depending on the level filling the tank (2). Device (1) according to one of Claims 6 or 7, characterized in that 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 that the closable fluid connection (35) is provided with a closure member (41) equipped with an electric control circuit (42) and in that the circuit ( 42) electrical control 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 the less in the activated state of the upper level sensor (40). 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 interior volume of the tank (2) and the inlet of the tank (2) connectable to the outlet (8A) of the primary circuit (8) is arranged in the lower third of the interior 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) connectable to the outlet (8B) of the primary circuit (8) of the 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). 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 recess (16 ) inside which the heat exchanger (7) which is a counter-current exchanger (7), preferably with plates, is adapted to be housed so as to extend at least partially inside the template overall of the tank (2). 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 lower than the level occupied by the inlet of the tank (2) connectable to the outlet (8B) of the primary circuit (8) of said heat exchanger (7). Device (1) according to one of Claims 1 to 11, characterized in that the tank (2) comprises an enclosure (51), an envelope (52) at least partially surrounding the enclosure (51) and an insulator (53 ) arranged between the enclosure (51) and the casing (52). 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) taken between the face exterior of the envelope (52) and the internal face of the enclosure (51) is in the part of the tank (2) extending above the part of the heating system (6) housed inside of 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). 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 component ( 32) displacement drive which is preferably a motor form a ready-to-mount assembly. 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 electrical resistor (61, 62) housed inside the tank (2), in that the tank (2) comprises, at the level of, or at least one of the electric resistors (61, 62), two orifices (21, 22) facing one (21) formed in the enclosure (51), the other (22) in the casing (52), these orifices (21, 22) being connected by a housing body (23) with a pierced bottom (231) forming a sheath connecting said orifices (21, 22) to each other, this casing 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 with a seal (24) threaded onto the electrical resistor (61, 62), this seal (24) in sealing bearing contact with the resistor (61, 62) sealingly sealing the hole (2311) of the bottom (231) of the body (23) of the box in the state through which said hole (2311) is traversed by the electrical resistor (61, 62).