GB1564486A - Hat water supplying apparatus - Google Patents
Hat water supplying apparatus Download PDFInfo
- Publication number
- GB1564486A GB1564486A GB49279/77A GB4927977A GB1564486A GB 1564486 A GB1564486 A GB 1564486A GB 49279/77 A GB49279/77 A GB 49279/77A GB 4927977 A GB4927977 A GB 4927977A GB 1564486 A GB1564486 A GB 1564486A
- Authority
- GB
- United Kingdom
- Prior art keywords
- water
- tank
- temperature
- heating
- circuit
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 title claims description 127
- 238000010438 heat treatment Methods 0.000 claims description 66
- 238000005406 washing Methods 0.000 claims description 14
- 239000008236 heating water Substances 0.000 claims description 10
- 230000001105 regulatory effect Effects 0.000 claims description 10
- 230000000694 effects Effects 0.000 claims description 9
- 238000004804 winding Methods 0.000 claims description 9
- 230000001276 controlling effect Effects 0.000 claims description 8
- 239000011435 rock Substances 0.000 claims description 6
- 238000013459 approach Methods 0.000 claims description 4
- 238000003303 reheating Methods 0.000 claims description 2
- 238000011144 upstream manufacturing Methods 0.000 description 4
- 238000006073 displacement reaction Methods 0.000 description 2
- 230000000903 blocking effect Effects 0.000 description 1
- 230000009977 dual effect Effects 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 230000002045 lasting effect Effects 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 230000000750 progressive effect Effects 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24D—DOMESTIC- OR SPACE-HEATING SYSTEMS, e.g. CENTRAL HEATING SYSTEMS; DOMESTIC HOT-WATER SUPPLY SYSTEMS; ELEMENTS OR COMPONENTS THEREFOR
- F24D19/00—Details
- F24D19/10—Arrangement or mounting of control or safety devices
- F24D19/1006—Arrangement or mounting of control or safety devices for water heating systems
- F24D19/1066—Arrangement or mounting of control or safety devices for water heating systems for the combination of central heating and domestic hot water
- F24D19/1069—Arrangement or mounting of control or safety devices for water heating systems for the combination of central heating and domestic hot water regulation in function of the temperature of the domestic hot water
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
- F23N—REGULATING OR CONTROLLING COMBUSTION
- F23N1/00—Regulating fuel supply
- F23N1/08—Regulating fuel supply conjointly with another medium, e.g. boiler water
- F23N1/10—Regulating fuel supply conjointly with another medium, e.g. boiler water and with air supply or draught
- F23N1/105—Regulating fuel supply conjointly with another medium, e.g. boiler water and with air supply or draught using electrical or electromechanical means
Description
(54) HOT WATER SUPPLYING APPARATUS
(71) We, SAUNIER DUAL. a French
Body Corporate of 250 route de l'Empereur, 92508 Rueil Malmaison, France, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: The present invention relates to hot water supplying apparatus.
In combination wall mounted gas heated boilers which use a heat exchanger through hot water passes to heat water in a storage tank, in general the storage tank is unable, during the course of a heating cycle, to absorb the entire power of the boiler throughout the duration of this cycle. The power that this heat-exchanger is able to absorb depends at all times upon the difference between the temperature of the heating liquid (space-heating water issuing from the heating element of the boiler) and that of the washing water contained in the storage tank.
Generally, in order to reduce costs, the heat-exchanger is so dimensioned that it is able to absorb all the power of the boiler only by accepting a considerable difference between the average temperature of the water in the heat-exchanger and the average temperature of the washing water in the storage tank, which means that the heat-exchanger will absorb the full power of the boiler only during a fraction of the time for re-heating the washing water tank, the period during which the full power of the boiler is utilized terminating at the moment when the temperature at which the space-heating water enters the heat-exchanger reaches the limiting value present for the functioning of the boiler and causes the burner to be extinguished or the supply of gas thereto to be reduced.
This means in practice that the actual time during which the washing water tank is re-heated will always be longer than the time that couuld be provided if it were possible to utilize the full power of the boiler until the final required temperature in the storage tank is reached.
As an example, taking a boiler having an effective power of 1000 Kcal/h, heating a 100 litre-tank to a temperature from 100C to 750C by means of an interior heatexchanger that will absorb the 1000 Kcal/h only when an average difference in temperature of 40"C occurs between the spaceheating water and the water in the tank, and if it is assumed that the thermostat or the temperature-limiting device of the boiler is set at 900C, then under these conditions full-power operation will cease as soon as the average temperature of the water in the tank reaches 9040, i.e. 50"C;; from this moment on the average power provided by the boiler will gradually diminish either by progressive reduction of the burner output or reduction of the duration of the heating peaks in the regulation cycles, and the duration of the second re-heating stage, i.e. 50 to 750C, will be proportionally much longer.
None of this would be too serious if, during all this time, the space-heating function of the radiators were not interrupted. However, although a cessation in space-heating lasting less than 15 minutes is generally hardly felt, beyond this period discomfort increases with the duration of the stoppage.
To avoid these drawbacks, solutions have been proposed wherein, when it is required to heat radiators and at the same time to reheat the hot washing water tank, the motorized multi-way valve, usually at two positions, moves to a third position in which the water issuing from the heating element of the boiler is directed in part to the heatexchanger of the tank, while another part of this water is directed to the radiator circuit, but the disadvantage of these solutions is that the temperature of the radiator heating water can no longer be adjusted to suit the requirements of the user since it has to be regulated in a fixed manner to give a high value of between 80 and 90"C. Consequently, such a boiler will be able to function only in such a way that it provides waves of heat which have to be controlled by an ambient temperature thermometer, and it is well-known that such a mode of operation does not provide great comfort and leads to a reduction in the performance of the installation.
Also known is a solution which consists in using a distributor, electrically driven by a motor. and enabling the tanks to be supplied with hot water to be given priority over the heating circuit, and an arrangement such that the circulating unit is started up as soon as the space-heating circuit has to be supplied with hot water. In this known arrangement, the circulating pump can be connected into the circuit simultaneously with the elements controlling the burner by way of two parallel control circuits, the first of which comprises in particular the contact of a thermostat in the space-heating circuit, while the second circuit comprises at least the contact of a thermostat for the tank as well as a relay for starting up the distributor motor. In this system the pump is started up only in dependence upon temperature requirements, even in the space-heating circuit.
Furthermore, in summer, part of the water from the tank circulating in a closed circuit, may pass into the radiators at the moment when the distributor is being reversed since the rate of circulation of the water does not drop to zero instantaneously.
According to the present invention there is provided apparatus for supplying hot water comprising a storage tank; an electrically controlled water heating element; a first, discharge-water circuit pipe passing through the water heating element and a second water circuit pipe passing through the water heating element and comprising a first branch for supplying water to space-heating radiators and a second branch for heating water in the storage tank; a reversing valve arrangement having first and second states in which it directs water from the heating element to the first branch and to the second branch of the second pipe, respectively; a thermostat responsive to the temperature of water in the storage tank for controlling which of its states the reversing valve arrangement is in; and first and second temperature sensors responsive to the temperature of water passing through the heating element by way of the first and second circuits, respectively; the arrangement being such that, in use, when water is discharged from the storage tank, it is replaced by water from the first water circuit pipe with the water heating element being energised during the replacement of the water if the temperature of the water in the storage tank falls below a predetermined value and with the water heating element not being energised during the replacement of the water if the temperature of the water does not fall to below said predetermined value.
The invention will be further described with reference to the accompanying drawings, in which: Figure 1 shows the general layout of one embodiment in the "summer" position during the heating of the tank; and
Figure 2 shows the layout of the embodiment in the "winter" position during the heating of the radiators.
Figure 1 illustrated diagrammatically a combination boiler comprising a heating element 4, a burner 2 controlled by an electric valve 3 regulating the flow of gas. and a casing of a reversing valve, which casing is designated generally by the reference numeral 1. Extending through the heating element 4 are a first circuit 5, which directly supplies storage tank 20 with pre-heated washing water, and a second circuit 7, called the space-heating circuit. The water issuing from the heating element by way of the space-heating circuit 7 flows in the direction of the arrow in the output pipe 8 and returns to the heating element through the return pipe 6, and passes either through the long circuit 9 supplying the radiators 10, or through a short circuit 11 supplying the re-heating means 12 for the storage tank 20.
The long and short circuits 9 and 11 run into the casing 1, out of which also runs a return pipe section 13 leading to a circulating pump 14 downstream of the casing 1 and upstream of the return pipe 6. The casing 1 of the reversing valve is formed by a lower compartment 15 and an upper compartment 16. The lower compartment 15 encloses the reversing valve member 17 proper, which is mounted on a pivoting arm 18 so as to close one or other of the openings to the circuits 9 and 11 terminating at the casing 1. The pivoting of arm 18 is controlled by a rod 19, biased by a spflng (not shown), this rod being connected to a differential diaphragm 21 which separates the upper compartment into two inner chambers 22 and 23. The chamber 23 is unrestrictedly subjected to the water-pressure, set up downstream of the pump 14, by means of a small pressure-pick-up pipe 24. The chamber 22 is connected either with the chamber 23 through a small pipe 25, or with the pipe 13 through a small pressure pick-up pipe 26 upstream of the pump 14.
This connection will depend upon the position of an oscillating vane 27 carrying a plug 28 which closes the pipe 25 while uncovering an opening 29, thus enabling the chambers 22 and 23 to communicate with each other by way of the small pipe 25; said plug may also close the opening 29 and at the same time uncover the end of the pipe 26.
A first electrical circuit Curl, connected to the main supply U for the apparatus, comprises in series the winding of the electric valve 30 which controls the oscillating vane 27, and a contact 31 controlled by a thermostat 32 which reacts to the temperature of the water within the storage tank 20. When energised, the moving-core electric valve 30 causes its core to rise and therefore brings about downward displacement of the plug 28.
A second circuit Cr2 connected across the terminals of the supply system U comprises in series the circulating pump 14, a resistor 33, a contact 34 also controlled by the thermostat 32, a contact 35 and a transformer 36. The contact 35 fitted at the end of the rod 19 is controlled by displacement of said rod in dependence upon the movement of the differential diaphragm 21. Furthermore, this contact 35 is also controlled by a "summer-winter" regulating handle shown diagrammatically at 37. When in the position H (Figure 2), the handle 37 locks the contact 35 in the closed position so as to switch the contact 34 for the purpose of continuously supplying the pump 14 through the lead 38 and the transformer 36.
The contacts 31 and 34 of the thermostat 32 are closed in the cold condition, and they open when the temperature of the water in the storage tank 20 approaches a predetermined temperature.
A rectifying bridge 39, the input of which is connected across the terminals of the transformer 36, supplies the winding 3 of the electric valve controlling the gas supply, by way of a reversing contact 40 which is in turn mounted at the end of the rod 19, acted upon by the movements of the differential diaphragm 21. The reversing contact 40 connects the electric valve 3 either through a circuit Cr2, comprising a thermistor 41 having a positive temperature coefficient and fitted close to the pipe 5 and controlling the temperature of the water in the discharge circuit. or by way of a circuit
Cr4, comprising a thermistor 42, likewise having a positive temperature coefficient, which thermistor is fitted close to the pipe 7 and controls the temperature of the water in the space-heating circuit.When the temperature of the water in the discharge circuit 5 or in the space-heating circuit 7 approaches a predetermined value, the resistance of the respective thermistor 41 or 42 increases, and the effect of this is to reduce the current in the electric valve 3 and therefore to limit the quantity of gas reaching the burner 2.
The above apparatus operates in the following manner:
First, the case of the "summer" position as illustrated in Figure 1 will be dealt with.
When starting up the apparatus, the user applies current to the apparatus by actuating a switch, not illustrated, and moves the "summer-winter" handle 37 into position
E, this causing the contact 35 to open. Since the water in the storage tank 20 is coin,.
the contacts 31 and 34 of the thermostat 32 are closed, and current passes through the circuit Cr,. this having the effect of energising the winding of the electric valve 30 and therefore of causing the vane 27 to pivot so that the plug 28 closes the opening 29 and, on the one hand, connects the chamber 23 with the pipe 6 downstream of the pump 14 by way of the small pipe 24, and on the other hand, connects the chamber 22 with the pipe 13 upstream of the pump 14 by way of the small pipes 25 and 26. At the same time, the current which passes through the lead 38 directly feeds the pump 14 which begins to turn.Consequently, the relatively high pressure set up downstream of the pump is established in the chamber 23 by way of the pipe 24, whereas the relatively low pressure upstream of the pump is established in the chamber 22 by way of the pipes 26 and 25. The pressure difference in the chambers 23 and 22 is converted into a movement of the differential diaphragm 21 and of the rod 19, and the effect of this is to cause the arm 18 to pivot; the blocking valve 17 then closes the return pipe 9 associated with the radiators, but opens the short circuit 11. All the water circulating in the output pipe 8 of the spaceheating circuit 7 then passes through the re-heating means 12 for the storage tank 20.
At the same time as the arm 18 pivots, the rod 19 closes the contact 35 so that the transformer 36 is fed, and the rod causes the reversing contact 40 to rock and this connects the electric valve 3, controlling the supply of gas, to the electric supply from the rectifying bridge 39, this connection passing through the thermistor 41. Gas is admitted to the burner 2 and the apparatus is operative.
As soon as the temperature of the water in the tank 20 has reached its predetermined value detected by the thermostat 32, the contact 31 opens again to interrupt passage of current in the circuit Curl. The electric valve 30 is no longer energised; the vane 27 rocks and then so does the arm 18 (as illustrated in Figure 2), and the contact 35 opens to cut off supply to the transformer 36 and therefore to the rectifying bridge 39.
Since the rectifying bridge 39 is no longer supplied with current, the electric valve 3 closes. At the same time the contact 34 is also re-opened to interrupt the current in the circuit Cr2, so that the pump stops. As soon as the temperature of the water in the storage tank has fallen again to a value at which the contacts 31 and 34 are closed again, the cycle for re-heating the tank recommences.
If the user draws water while the burner 2 is operating and the temperature of the tank 20 is rising, the drawn-off water is re placed by hot water from the discharge circuit 5 of the boiler, and the effect of this is to maintain or increase the temperature of the water within the tank and not to reduce this temperature.
When the user draws water while the tank 20 is hot, the burner 2 is not operated and the discharged water is replaced by cold water drawn from the discharge circuit 5.
However, when the tank-water temperature, detected by the sensor of the thermostat 20, drops below the envisaged value, the reversing valve moves into the position for heating the tank and therefore for starting up the apparatus and at the same time feeding the tank with hot washing water through the discharge circuit.
The case where the apparatus is in the '^winter" position will now be dealt the The "summer-winter" handle 37 will have been brought into the position H by the user so as to lock the contact 35 in the closed position.
If the hot-water tank 20 and the radiators are all cold, for example when the apparatus is being started up, the contacts 31 and 34 are closed, and the Figure 1 situation, in which the tank is heated through the short circuit 11, is reached.
As soon as the tank 20 is hot, the contacts 31 and 34 open, and the current in
the circuit Crl is interrupted, so that the vane 27 rocks, whereupon the arm 18 also rocks. The apparatus is in the position for heating the radiators as illustrated in Figure 2. Since the handle 37 is in the H position, the contact 35 is closed, the transformer 36 is under voltage, and the pump 14 is con- tinuously supplied through the lead 38. The reversing contact 40 establishes connection between the rectifying valve 39, the thermistor 42 and the winding 3 of the electric valve by way of the circuit Cr4. Gas is then admitted to the burner, and heating of the radiators continues.When the temperature of the space-heating water in the pipe 8 approaches a predetermined limiting temperature, the resistance of the thermistor 42 increases, and the current passing through the winding 3 of the electric valve diminishes, and this has the effect of progressively cutting off the supply of gas to the burner and consequently of regulating the supply of gas as a function of the temperature of the space-heating water. the pump continuing to turn however.
As soon as the temperature of the tank has dropped below a predetermined value (the threshold value for triggering the thermostat 32), the reversing valve moves into the position for heating the tank, that is to say, re-heating of the discharge water is given priority.
If the user draws water, the discharged water is replaced in the tank by hot water from the discharge circuit 5, and this enables the water in the tank to be maintained at the required temperature. However, if the quantity drawn off is considerable and the temperature of the tank still drops below the envisaged value, the reversing valve moves into the position for heating the tank and at the same time for energizing the winding 3 so that the burner 2 operates whereby the tank is supplied with hot washing water through the discharge circuit 5 of the apparatus, this having the effect of considerably reducing the time required for reheating the tank and therefore of interrupting circulation of water in the radiators for a shorter period.
The above apparatus therefore offers the advantage of permitting the storage of hot water and particularly a large volume of hot washing water, since the washing water is supplied from the discharge circuit of the combination boiler, while at the same time the storage tank is of small volume and therefore of reduced size.
WHAT WE CLAIM IS:- 1. Apparatus for supplying hot water comprising a storage tank; an electrically controlled water heating element; a first, discharge-water circuit pipe passing through the water heating element and a second water circuit pipe passing through the water heating element and comprising a first branch for supplying water to space-heating radiators and a second branch for heating water in the storage tank; a reversing valve arrangement having first and second states in which it directs water from the heating element to the first branch and to the second branch of the second pipe, respectively; a thermostat responsive to the temperature of water in the storage tank for controlling which of its states the reversing valve arrangement is in; and first and second temperature sensors responsive to the temperature of water passing through the heating element by way of the first and second circuits, respectively, the arrangement being such that, in use, when water is discharged from the storage tank, it is replaced by water from the first water circuit pipe with the water heating element being energised during the replacement of the water if the temperature of the water in the storage tank falls below a predetermined value and with the water heating element not being energised during the replacement of the water if the temperature of the water does not fall to below said predetermined value.
2. A regulating system according - to claim 1, wherein the heating element is a gas burner controlled by an electrically operated valve.
3. Apparatus according to claim 2 wherein the thermostat has a first switch
**WARNING** end of DESC field may overlap start of CLMS **.
Claims (10)
1. Apparatus for supplying hot water comprising a storage tank; an electrically controlled water heating element; a first, discharge-water circuit pipe passing through the water heating element and a second water circuit pipe passing through the water heating element and comprising a first branch for supplying water to space-heating radiators and a second branch for heating water in the storage tank; a reversing valve arrangement having first and second states in which it directs water from the heating element to the first branch and to the second branch of the second pipe, respectively; a thermostat responsive to the temperature of water in the storage tank for controlling which of its states the reversing valve arrangement is in; and first and second temperature sensors responsive to the temperature of water passing through the heating element by way of the first and second circuits, respectively, the arrangement being such that, in use, when water is discharged from the storage tank, it is replaced by water from the first water circuit pipe with the water heating element being energised during the replacement of the water if the temperature of the water in the storage tank falls below a predetermined value and with the water heating element not being energised during the replacement of the water if the temperature of the water does not fall to below said predetermined value.
2. A regulating system according - to claim 1, wherein the heating element is a gas burner controlled by an electrically operated valve.
3. Apparatus according to claim 2 wherein the thermostat has a first switch
forming part of a first electrical circuit controlling the heating element, and a second switch forming part of a second electrical circuit comprising in series a circulating pump and a third switch which it itself controlled by a user operable "summer-winter" regulating member and wherein the electric valve of the gas burner is fed from a rectifying bridge via a reversing contact either through a circuit comprising the first temperature sensor or through a circuit comprising the second temperature sensor the movement of said reversing contact being controlled by the movement of the reversing valve arrangement.
4. Apparatus according to claim 3, wherein an input of the rectifying bridge is connected across the terminals of a transformer arranged in series with the third switch.
5. Apparatus according to claims 3 and 4, wherein the third switch is controlled by the movement of the reversing valve when said regulating member is in the "summer" position to feed the transformer.
6. Apparatus according to claim 3 wherein the regulating member locks the third switch in the closed position when at the "winter" setting.
7. Apparatus according to claim 3, wherein the reversing contact is mounted on an actuating rod of the reversing valve arrangement operated by the movement of a control diaphragm of said valve.
8. Apparatus according to any one of the preceding claims wherein the first and second temperature sensors are thermistors.
9. Apparatus according to any one of the preceding claims arranged as a single unit for mounting on a wall.
10. Hot water supply apparatus constructed and arranged to operate substantially as hereinbefore described with reference to the accompanying drawings.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR7638062A FR2374601A1 (en) | 1976-12-17 | 1976-12-17 | REGULATION SYSTEM FOR MIXED WALL-MOUNTED GAS BOILERS WITH DOMESTIC HOT WATER PRODUCTION BY REHEATING AN ACCUMULATION TANK |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| GB1564486A true GB1564486A (en) | 1980-04-10 |
Family
ID=9181186
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB49279/77A Expired GB1564486A (en) | 1976-12-17 | 1977-11-25 | Hat water supplying apparatus |
Country Status (4)
| Country | Link |
|---|---|
| ES (1) | ES464899A1 (en) |
| FR (1) | FR2374601A1 (en) |
| GB (1) | GB1564486A (en) |
| IT (1) | IT1088497B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| LU83072A1 (en) * | 1981-01-21 | 1982-09-10 | Wanson Constr Mat Therm | COMBINED ELECTRIC BOILER |
| CN117073084B (en) * | 2023-08-21 | 2024-04-23 | 珠海格莱克科技有限公司 | Humidity control apparatus and method for stabilizing water temperature of humidity control apparatus |
-
1976
- 1976-12-17 FR FR7638062A patent/FR2374601A1/en active Granted
-
1977
- 1977-11-25 GB GB49279/77A patent/GB1564486A/en not_active Expired
- 1977-12-09 ES ES464899A patent/ES464899A1/en not_active Expired
- 1977-12-16 IT IT30805/77A patent/IT1088497B/en active
Also Published As
| Publication number | Publication date |
|---|---|
| ES464899A1 (en) | 1978-09-01 |
| IT1088497B (en) | 1985-06-10 |
| FR2374601A1 (en) | 1978-07-13 |
| FR2374601B1 (en) | 1979-04-13 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PS | Patent sealed [section 19, patents act 1949] | ||
| PCNP | Patent ceased through non-payment of renewal fee |