JPH11241864A - Method and device for supplying hot water - Google Patents

Abstract

PROBLEM TO BE SOLVED: To supply hot water having temperature approximately equal to a set temperature, when re-supply of hot water is effected after the lapse of a comparatively short time commencing from a stop of supply of hot water. SOLUTION: A hot water supply device comprises a heat-exchange part 10, a combustion part 20, and a piping 50 for supply of hot water flowing through the heat-exchange part 10. When a hot water supply faucet 55 arranged downstream of the piping 50 is opened, a water flow is detected by a flow sensor FL (a detecting means). A control unit 60 executes combustion by a combustion part in response to detection of the water flow and performs supply of hot water. When a state not to detect a water flow occurs, supply of hot water is not immediately stopped but combustion is continued in a short time (embers combustion). When a quantity of combustion heat per unit time during supply of hot water is high and sufficient heat rise after shut off is expected, embers combustion may not be performed. The more a quantity of combustion heat per unit time during supply of hot water is lower, namely, the less heat rise after shut off is expected, the more a total quantity of combustion heat generated by the embers combustion is increased.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hot water supply apparatus capable of improving re-hot water supply characteristics.

[0002]

2. Description of the Related Art A general hot water supply apparatus includes a heat exchange section, a combustion section, and a hot water supply pipe passing through the heat exchange section. The pipe is provided with detection means for detecting the flow of water. When the hot water tap provided at the downstream end of the pipe is opened, this detecting means detects the flow of water in the pipe. In response to the detection signal, the control means performs combustion in the combustion section,
Heat the heat exchange section. The water in the pipe is heated in the process of passing through the heat exchanging section to become hot water, and is discharged from the hot water tap. The control means controls the amount of heat of combustion in the combustion section so that the hot water temperature becomes the set temperature. And the water tap is closed,
When the detection means no longer detects the flow of water in the pipe,
Stop the combustion in the combustion section. In this way, hot water supply is stopped.

[0003] In the above hot water supply apparatus, a phenomenon in which the temperature of the hot water remaining in the heat exchange section temporarily stops after the hot water supply is stopped, a so-called post-boiling phenomenon occurs. This is because the amount of heat stored in the heat exchange unit is transmitted to the hot water remaining in the heat exchange unit immediately after the stop of hot water supply. Recently, the hot water supply device takes about one second from the start of re-water supply to the start of heat transfer to the heat exchange section. During this time, only the water enters the hot water supply device and is not heated. In recent years, when this amount of heat is supplemented by the amount of heat generated by post-boiling, and the post-boiling phenomenon is actively used to open the hot water tap within a predetermined period of time, for example, 5 minutes after hot water supply is stopped, and to re-heat water. A hot water supply device capable of discharging hot water having a temperature close to a set temperature even immediately after the start of re-hot water supply has been developed.

[0004]

However, in order to stabilize the hot water immediately after re-heating within 5 minutes by utilizing the after-boiling phenomenon, it is necessary to use the heat exchange unit stored at the time of stopping the hot water supply. It is necessary to make the relative relationship between the amount of heat and the amount of hot water or water stored in the heat exchange unit an appropriate range. If the heat storage amount is too large with respect to the amount of retained hot water, post-boiling will be remarkable, and the temperature of the retained hot water will rise excessively.If the heat storage amount is too small with respect to the amount of retained hot water, sufficient after-boiling will be obtained. It is not possible. Therefore, it is necessary to appropriately design the heat capacity (mass) of the heat exchange unit and the amount of retained water (diameter and length of a pipe passing through the heat exchange unit), and the design has great restrictions. Further, when a hot water supply device having a large combustion capacity (number of combustions), for example, a hot water supply device of No. 32 is used in a general household, if the set temperature is about 40 degrees, even if the hot water tap is fully opened, combustion is performed at the maximum combustion capacity. It only generates 1/2 to 1/3 of the amount of combustion heat. In this case, although the heat exchange section has a large heat capacity, only a part of the heat exchange section is heated, so that the post-boil is small and the hot water immediately after re-hot water supply cannot be brought close to the set temperature.

[0005]

According to a first aspect of the present invention, the heat from a heat generating section is supplied to a heat exchange section through which a hot water supply pipe passes, thereby heating water flowing in the pipe and supplying hot water. The method is characterized in that heat is continuously supplied to the heat exchange unit for a limited time even after water stops flowing in the pipe. According to a second aspect of the present invention, there is provided a heat exchange section, a combustion section for supplying combustion heat to the heat exchange section, a hot water supply pipe passing through the heat exchange section, and a detecting means for detecting a flow of water in the pipe. And a control unit for supplying hot water by performing the combustion in the combustion unit in response to the detection of the water flow by the detection unit. The combustion is continued for a limited time from the point in time when the state is switched to the detection state, that is, from the point in time when hot water supply is stopped.

According to a third aspect of the present invention, in the hot water supply apparatus according to the second aspect, the pipe comprises a heat receiving pipe passing through a heat exchange section;
A water supply pipe and a hot water supply pipe respectively connected to the inlet and the outlet of the heat receiving pipe, and a bypass pipe connected to the water supply pipe and the hot water supply pipe in parallel with the heat receiving pipe, and a bypass valve is provided in the bypass pipe. The control means controls the bypass valve in accordance with the temperature of the hot water coming out of the heat exchange section or the elapsed time since the last stop of hot water supply when the water flow is detected by the detection means. And According to a fourth aspect of the present invention, in the hot water supply apparatus according to the second or third aspect, the control means determines a total amount of combustion heat to be provided by continuous combustion at the time of hot water supply stop according to information on a combustion state at the time of hot water supply. It is characterized in that determination is made and continuous combustion is performed for a time during which the total combustion heat is obtained. According to a fifth aspect of the present invention, in the hot water supply apparatus according to the second or third aspect, the control means calculates a continuous combustion time according to information on a combustion state at the time of hot water supply when the hot water supply is stopped. It is characterized in that continuous combustion is performed for a predetermined time with a predetermined amount of combustion heat per unit time.

According to a sixth aspect of the present invention, in the hot water supply apparatus according to the fourth or fifth aspect, the information on the combustion state at the time of hot water supply includes one or both of a heat quantity of combustion per unit time and a set time. It is characterized by. According to a seventh aspect of the present invention, in the hot water supply apparatus according to the fourth or fifth aspect, the combustion section has a plurality of combustion areas in which combustion can be independently controlled. And information on the number of combustion areas in the combustion state at the time of hot water supply, wherein the control means calculates the total amount of combustion heat or the continuous combustion time corresponding to the number of the combustion areas at the time of hot water supply stop. . According to an eighth aspect of the present invention, in the hot water supply apparatus according to any one of the fourth to seventh aspects, the control means determines the total combustion heat amount or the continuous combustion time during the continuous combustion in accordance with the outside air temperature. It is characterized by the following. According to a ninth aspect of the present invention, in the hot water supply apparatus according to any one of the fourth to eighth aspects, the pipe is a heat receiving pipe passing through a heat exchange unit, and a water supply pipe and a hot water supply connected to an inlet and an outlet of the heat receiving pipe, respectively. Tubes and
A water supply pipe and a bypass pipe connected to the hot water supply pipe in parallel with the heat receiving pipe, wherein the control means is adapted to cope with an incoming water temperature entering the hot water supply pipe from the water supply pipe via the bypass pipe, and Is characterized in that the total combustion heat amount or the continuous combustion time is determined.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the hot water supply device
A heat exchange section 10 having a large combustion capacity (for example, No. 32) and having a large heat capacity having a large number of fins 11; and a combustion section 20 (heat generation section) for supplying a heat of combustion to the heat exchange section 10. have. The combustion section 20 has three combustion areas 21, 22, 23. The gas supply pipe 30 includes a main pipe section 35 and 3 branches from the main pipe section 35.
It has two branch pipe sections 31, 32, 33. Main pipe 3
5 is provided with a main opening / closing valve 45 and a proportional valve 46, and branch pipe portions 31, 32, 33 are provided with sub opening / closing valves 41, 42,
43 are provided.

A pipe 50 for supplying hot water includes a heat receiving pipe 51 passing through the heat exchange section 10, a water supplying pipe 52 connected to an inlet end of the heat receiving pipe 51, and a hot water supplying pipe connected to an outlet end of the heat receiving pipe 51. 53. The hot water supply pipe 53 has a water amount control valve 5.
4 and a hot water tap 55 is provided at a downstream end thereof. Further, the pipe 50 has two bypass pipes 56 and 57 in parallel with the heat receiving pipe 51. The connection points of the bypass pipe 56 closer to the heat exchange section 10, the water supply pipe 52, and the hot water pipe 53 are indicated by P1 and P2. The connection points of the bypass pipe 57 farther from the heat exchanger 10 and the water supply pipe 52 and the hot water supply pipe 53 are indicated by P3 and P4. This bypass pipe 5
7 is provided with a bypass valve 58 composed of an electromagnetic switching valve.

The water supply pipe 52 is provided with an incoming water temperature sensor TH _IN for detecting the incoming water temperature T _IN . Also,
The hot water supply pipe 53 is provided with an outlet temperature sensor TH _OUT for detecting the temperature T _OUT of hot water from the outlet of the heat exchange unit 10 between the heat exchange unit 10 and the connection point P2. Further, the hot water supply pipe 53 has a hot water temperature sensor TH for detecting the hot water temperature T _MIX downstream of the connection point P4.
_{A MIX} and a flow sensor FL (detection means for detecting a water flow) for detecting the amount of water flowing through the pipe 50, that is, the amount of hot water, are provided.

The hot water supply apparatus further includes a control unit 60 (control means) including a microcomputer, and a remote controller 65 for sending information of the user set temperature T _S to the control unit 60. Control unit 60
Is the set temperature T _S and the detected temperature T _IN ,
Based on T _OUT , T _MIX , the detected flow rate from the flow sensor FL, etc., the ignition mechanism and the valves 41, 42, 4 for gas supply
3, 45, 46, the water amount control valve 54, and the bypass valve 58 are controlled.

The hot water supply apparatus includes a pipe for reheating the bath that passes through the heat exchange section 10 and a hot-water pipe that is connected from the hot water supply pipe 53 to the pipe for reheating the bath. The illustration is omitted because it is not the gist.

In the hot water supply apparatus having the above configuration, the control unit 60 executes a control routine shown in FIG. More specifically, it is determined whether or not the flow rate detected by the flow sensor FL has exceeded a very low set threshold value, in other words, whether or not the user has opened the hot water tap 55 and water is flowing through the pipe 10. (Step 101). Here, it waits until an affirmative judgment is made. When an affirmative determination is made, the combustion lamp is turned on to execute hot water supply control (step 102). In this hot water supply control, first, the main on-off valve 45 and at least one sub-on / off valve 41 to 43 are opened and an ignition operation is performed, so that combustion in the combustion unit 20 is started. Then, it calculates the feedforward control component based and flow rate detected by the flow sensor FL, the user set temperature T _S set by the incoming water temperature T _IN and a remote controller 65 detected by the temperature sensor TH _IN, the temperature sensor A feedback control component is calculated based on tapping temperature T _MIX detected at TH _MIX and set temperature T _S. Then, based on the control value obtained by adding the feedback control component to the feedforward control component, the supply gas amount, that is, the amount of combustion heat per unit time is controlled so that the tapping temperature T _MIX becomes the set temperature T _S.

More specifically, when the required amount of combustion heat per unit time is small, the sub-opening / closing valve 41 corresponding to one combustion region 21 in the combustion section 20 is opened, and the other sub-opening / closing valves 42 and 43 are closed. Leave this combustion area 21
Perform combustion only at one side (one-sided combustion). In this state, by controlling the proportional valve 46, the supply gas amount, and thus the combustion heat amount per unit time, is steplessly controlled up to the first upper limit. If the required amount of combustion heat per unit time exceeds the first upper limit, the two sub-opening / closing valves 41 and 42 are opened to perform combustion in the combustion regions 21 and 22 (two-sided combustion). Then, by controlling the proportional valve 46, the supply gas amount is controlled steplessly within the range up to the second upper limit value. When the required amount of combustion heat per unit time exceeds the second upper limit, all the sub-opening / closing valves 41 to 43 are opened and the proportional valve 46 is controlled to execute combustion in the combustion regions 21 to 23. Then (three-sided combustion), the supply gas amount is steplessly controlled within the third upper limit value, that is, the range up to the maximum combustion capacity.

If the required amount of combustion heat per unit time exceeds the maximum combustion capacity, the water flow control valve 54 is throttled to restrict the amount of hot water to an amount commensurate with the maximum combustion capacity. The bypass valve 58 is open in normal hot water supply control, but is closed when the set temperature is extremely high, for example, at 60 ° C. or higher. The opening timing of the bypass valve 58 in the initial stage of hot water supply control will be described later.

The hot water supply control is performed in the next step 103,
The process is continued until the flow rate detected by the flow sensor FL is determined to be lower than the threshold value, that is, until the user closes the hot water tap 55 to change to the water flow non-detection state and determine that the hot water supply is stopped. When it is determined in step 103 that the water flow is not detected, the process proceeds to step 104. Here, it is determined whether or not three-side combustion was performed during the hot water supply control. If a positive determination is made here, the main on-off valve 45 and the auxiliary on-off valve 41
Close to 43 to immediately stop the combustion state (zero residual combustion time). In the case of three-sided combustion, a sufficient amount of combustion heat is given to the heat exchange unit 10 and a large amount of heat is stored. Therefore, even if the heat capacity (mass) of the heat exchange unit 10 is large, sufficient after-boiling can be expected. After one minute, the temperature is higher than a predetermined temperature (for example, 60
° C or more).

If a negative determination is made in step 104,
That is, when it is determined that the apparatus is in the one-sided combustion state or the two-sided combustion state, first, the combustion lamp is turned off to give the user a sense of security that the appliance is operating normally, and then the eruption state is entered. The combustion time t ₀ (continuous combustion time) is calculated (step 105). The residual combustion time t ₀ is set in accordance with the number of combustion zones. If it is determined that one surface combustion state, than when it is determined that the dihedral combustion state, remaining fire burn time t ₀ becomes longer. For example, in the case of a one-sided combustion state, it is set to 0.
8 seconds, and 0.5 seconds in the case of two-sided combustion.

The residual combustion time t ₀ may be varied based on T _OUT (or T _S ). In other words, because we want to temperature range of the temperature after the lapse of 1 minute, if T _OUT is low t ₀
Is larger and T _OUT is higher, it is preferable to reduce t ₀ . If T _OUT is high, we want to reduce t ₀ ,
Conversely units of time (1/100 sec) is reduced, since control is difficult, if T _OUT is high Step 103
It is preferable to count t ₀ after setting the proportional valve to the minimum opening after the result becomes NO in the above.

Next, the combustion state is continued for the above-mentioned residual combustion time t ₀ (step 106). In the present embodiment, when the two-sided combustion is performed during the hot water supply combustion control, the two-sided combustion state is set to the second upper limit value or a predetermined supply gas amount (a predetermined amount of combustion heat per unit time). Prolong the combustion. If one-sided combustion is performed during the hot water supply control, the sub-opening / closing valve 32 is opened to set a two-sided combustion state, and the combustion is continued to be extended with the predetermined supply gas amount. As is apparent from this description, in the case of one-sided combustion or two-sided combustion at the time of hot water supply control, the amount of combustion heat applied to the heat exchange unit 10 per unit time is small and the amount of heat stored is small, so that after-boiling is small. However, by performing this residual combustion and adding the amount of heat of combustion to the hot water retained in the heat exchange unit 10, the temperature of the retained hot water can be raised to a predetermined temperature or higher (60 ° C. or higher). is there. In the case where the dihedral combustion one surface combustion when the hot water supply control, there is a difference in the amount of stored heat of the heat exchange portion 10, it was different for remaining fire burn time t ₀ corresponding, granted in turn for remaining fire combustion Since the total amount of heat of combustion is varied, the temperature of the retained hot water in the heat exchange unit 10 can be equalized at the end of the residual combustion or at the elapse of a predetermined time, for example, one minute.

In the case of two-sided combustion at the time of hot water supply, the residual combustion may be performed by the two-sided combustion in the same manner as described above. .
However, in the case of one-sided combustion at the time of hot water supply, it is needless to say that the combustion time is made longer than that of the above-described example, and that the total amount of combustion heat due to residual combustion is larger than that of the two-sided combustion at the time of hot water supply.

The above-mentioned residual combustion control is terminated when it is determined that the set time t _{0 has} elapsed (step 107), the combustion is stopped (step 108), and the process returns to the standby state of step 101. When the user opens the hot water tap 55 again, a positive determination is made in step 101 and the hot water supply control (step 10).
Start 2). Although the temperature of the staying water in the heat exchange unit 10 described above gradually decreases due to heat radiation, if the restart of hot water supply is within a predetermined time, for example, within 5 minutes, the temperature is sufficiently warm. Hot water with hot water 5
5 can be discharged. Therefore, the user can enjoy warm water only after putting up low-temperature water or water for a very short period of time at the beginning of hot water supply, that is, time until the staying hot water reaches hot water tap 55.

Next, the control of the initial stage of hot water supply, in particular, the control of the bypass valve 58 will be described in detail. This bypass valve 58
Before describing the control, the mixing of the hot water from the heat exchange unit 10 and the water from the bypass pipes 56 and 57 will be described in advance. When the bypass valve 58 is closed, the mixing ratio of hot water from the heat exchange unit 10 and water from the bypass pipe 56 is X: (1−X). Therefore, tapping temperature T _MIX can be expressed by the following equation. T _MIX = T _OUT × X + T _IN (1−X) (1) When the bypass valve 58 is open, hot water from the heat exchange unit 10 and water from the two bypass pipes 56 and 57 are provided. Is Y: (1-Y). Therefore, tapping temperature T _MIX can be expressed by the following equation. T _MIX = T _OUT · Y + T _IN (1−Y) (2) Of course, Y <X, and in this embodiment, Y = 0.45, X
= 0.7.

As a result of the after-boiling and residual combustion, the temperature of the stagnant hot water reaches a peak, for example, one minute after the stop of hot water supply.
Thereafter, the temperature gradually decreases due to heat radiation. In this embodiment,
Even when about 5 minutes have elapsed since the hot water supply was stopped, the staying hot water in the heat exchange unit 10 is at a temperature close to the set temperature. At the start of hot water supply, the hot water staying in the heat exchange unit 10 is detected by the outlet temperature sensor T _OUT .
It is determined whether or not to open the bypass valve 58 early based on the outlet temperature T _OUT (retained hot water temperature), the set temperature T _S, and the incoming water temperature T _IN . That is, the tapping temperature T _MIX is predicted based on the above equations (1) and (2). Then, the expected tapping temperature T _MIX closer to the set temperature T _S is selected. In other words, whether to open or close the bypass valve 58 is selected. When the bypass valve 58 is opened, the bypass valve 58 is opened early (that is, before the time when the accumulated hot water first reaches the connection point P4). Thus, the actual leaving water temperature immediately after the start hot water can be brought close to the set temperature T _S.

For example, the temperature T _OUT of the stagnant hot water at the start of hot water supply is 55 ° C. and the incoming water temperature T _IN is 2 ° C.
0 ° C. and the set temperature T _S is 40 ° C.
The expected tapping temperature T _MIX based on equation (1) is 44.5 ° C., and the expected tapping temperature T _MIX based on equation (2) is 39.25 °.
C. The temperature close to the set temperature T _S is the predicted tapping temperature T _MIX based on the equation (2), and in this case, the bypass valve 58 is opened at the above timing. When the set temperature T _S is 43 ° C. under the same conditions, the _{reason for} being close to the set temperature T _S is as follows.
Since the expected tapping temperature T _MIX based on equation (1), in this case, the bypass valve 58 is not opened at the timing described above, and all the retained hot water is discharged from the hot water tap 55, and the bypass is set after the tapping temperature is stabilized. Open valve 58. In this case, the supply gas amount is increased in advance before the opening operation of the bypass valve 58.

The present invention is not limited to the above-described embodiment, but can adopt various forms. For example, when hot water supply is stopped, how much the total heat of combustion due to residual combustion is
The determination may be performed steplessly in accordance with more accurate information on the combustion state, for example, the actual amount of combustion heat (supplied gas amount) per unit time immediately before stopping hot water supply. That is, the smaller the actual hot water supply combustion heat amount per unit time, the larger the total combustion heat amount by residual combustion. The amount of combustion heat per unit time is calculated based on the open / close information of the sub-open / close valves 41 to 43 and the proportional valve 4
6, or may be calculated from the set temperature, the incoming water temperature, and the amount of hot water. With this configuration, the temperature of the staying hot water at a predetermined time, for example, one minute after the stop of the hot water supply can be made more accurately.
When the total calorific value is determined, the residual combustion is performed by the time integration of the calorific value per unit time until the determined total calorific value is reached (in other words, for a limited time). The amount of heat of combustion per unit time can be determined arbitrarily,
It may be always constant or may be the amount of combustion heat per unit time when hot water supply is stopped. If the amount of combustion heat per unit time due to the residual combustion is always constant, the residual combustion time is determined directly instead of the total combustion heat, and the residual combustion is performed for the determined residual combustion time. I do. Similarly,
Whether or not to perform residual combustion may be determined based on the actual amount of hot water supply combustion heat per unit time. For example, when the hot water supply heat quantity is higher than the threshold value, the residual combustion is not performed (the residual combustion time is zero). When the heat quantity is lower than the threshold value, the residual combustion is performed in accordance with the hot water supply heat quantity as described above. .

The total amount of combustion heat or residual combustion time due to residual fire may be determined in accordance with other combustion conditions, for example, a user-set temperature. It may be determined according to the amount of heat.
That is, the higher the user-set temperature, the greater the total amount of combustion heat and the longer the residual combustion time.

The total amount of combustion heat due to residual fire or the residual combustion time may be determined in accordance with one or both of the hot water supply heat amount and the user set temperature and the outside air temperature. That is, the lower the outside air temperature is, the more the total amount of combustion heat by the residual combustion is increased, or the longer the residual combustion time is, to compensate for the heat release.

Further, the hot water supply pipe 50 has a bypass pipe 56.
Is provided, in addition to any one or two or all of the hot water supply heat energy, the user set temperature, and the outside air temperature, and the input water temperature T _IN detected by the input water temperature sensor TH _IN. Correspondingly, it may be possible to determine how much the total amount of combustion heat due to residual fire or the residual combustion time is. That is, the lower the incoming water temperature T _IN , the greater the total amount of combustion heat due to residual combustion, or the longer the residual combustion time,
It compensates for the drop in tapping temperature due to hot and cold mixing.

Selection of opening and closing of the bypass valve 58 at the initial stage of hot water supply control is performed when the predicted hot water supply temperature based on the equation (1) exceeds a predetermined temperature, for example, 3 ° C. higher than the upper limit temperature. The opening operation of the bypass valve 58 in the initial stage may be determined without performing the above operation, and safety may be ensured.
If the predicted tapping temperature based on the equation (2) is lower than the set temperature by a predetermined temperature, for example, a lower limit temperature lower by 3 ° C., the closing of the bypass valve 58 in the initial stage is determined without performing the above comparison, and the convenience is improved. May be pursued.

When selecting the opening / closing of the bypass valve 58 at the beginning of the hot water supply, not the detection information of the outlet temperature sensor TH _OUT but the combustion heat amount (supply gas amount) at the time of hot water supply stop, the outside air temperature, and the hot water supply restart from the hot water supply stop. And the elapsed time
The temperature of the stagnant water may be expected. The selection of the opening and closing of the bypass valve 58 may be made based on only the elapsed time from the stop of hot water supply to the re-hot water supply. For example, if a predetermined time, for example, three minutes, has elapsed, the bypass valve 58 is opened in the initial stage of hot water supply, and if three minutes have elapsed, the bypass valve 58 is closed in the initial stage of hot water supply. The bypass valve 58 may be closed in principle at the time of hot water supply, and may be opened as needed only in the initial stage.

Instead of the open / close type bypass valve, a water amount control type bypass valve, for example, a bypass valve whose opening can be continuously adjusted by driving a gear motor may be used. In this case, the outlet temperature T _OUT and the incoming water temperature T _{IN in the} initial stage of hot water supply.
By adjusting the opening degree of the bypass valve according to the temperature, the tapping temperature can be made closer to the set temperature.

In FIG. 1, the bypass pipe 57 and the bypass valve 58 are omitted, and the water from the bypass pipe 56 and the heat exchange section 1 are removed.
Hot water from 0 may be mixed. In this case, the mixing ratio of hot and cold water is constant. In addition, the bypass pipe 56,
57 may be omitted. In particular, in the case of a hot water supply device having a large combustion capacity, the residual combustion may be performed unconditionally, or the residual combustion may be performed so as to have a constant total combustion heat regardless of the combustion state at the time of hot water supply. Good. When a combustion lamp is provided in the remote controller 65 and hot water combustion and residual combustion are performed, the combustion lamp may be turned on, or combustion lamps corresponding to hot water combustion and residual combustion may be provided.
The lighting may indicate the corresponding combustion.

[0033]

As described above, according to the first and second aspects of the present invention, the hot water supply section is heated for a limited period of time after the hot water supply is stopped, so that the hot water supply characteristic at the restart of the hot water supply is improved. Can be improved. According to the third aspect of the present invention, by controlling the bypass valve at the time of restarting hot water supply, the effect of the continuous combustion can be more effectively utilized to make the tapping characteristics preferred by the user. According to the invention of claims 4 to 7, by performing continuous combustion according to the combustion state at the time of hot water supply, it is possible to stabilize hot water supply characteristics at the time of restarting hot water supply. Claim 8
According to the invention, by performing the continuous combustion in consideration of the heat radiation from the stop of the hot water supply, the tapping characteristics at the restart of the hot water supply can be further stabilized. According to the ninth aspect of the present invention,
By performing continuous combustion in consideration of the mixing of water from the bypass pipe, it is possible to further stabilize the tapping characteristics when restarting hot water supply.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a hot water supply apparatus according to an embodiment of the present invention.

FIG. 2 is a flowchart showing a control routine executed by the water heater.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Heat exchange part 20 Combustion part 21-23 Combustion area 50 Hot water supply pipe 51 Heat receiving pipe 52 Water supply pipe 53 Hot water supply pipe 56, 57 Bypass pipe 58 Bypass valve 60 Control unit (Control means) FL flow sensor (Detection means)

Claims (9)

[Claims] In a method of supplying water by heating water flowing in a pipe by supplying heat from a heat generating section to a heat exchange section through which a pipe for hot water supply passes, water does not flow in the pipe. A hot water supply method characterized in that heat is continuously supplied to the heat exchange section for a limited time after the hot water supply. 2. A heat exchange section, a combustion section for supplying combustion heat to the heat exchange section, a hot water supply pipe passing through the heat exchange section, a detecting means for detecting a flow of water in the pipe, A hot water supply apparatus comprising: a control unit that performs hot water supply by performing combustion in the combustion unit in response to the water flow detection by the detection unit; wherein the control unit changes a water flow detection state from the water flow detection state by the detection unit to a water flow non-detection state. A hot water supply apparatus characterized in that the combustion is continued for a limited time from the time when the hot water supply is switched to, that is, the time when the hot water supply is stopped. 3. The pipe according to claim 1, wherein the pipe is a heat receiving pipe passing through a heat exchange section,
A water supply pipe and a hot water supply pipe respectively connected to the inlet and the outlet of the heat receiving pipe, and a bypass pipe connected to the water supply pipe and the hot water supply pipe in parallel with the heat receiving pipe, and a bypass valve is provided in the bypass pipe. The control means, when the detection means detects the water flow,
The hot water supply apparatus according to claim 2, wherein the bypass valve is controlled in accordance with a temperature of hot water coming out of the heat exchange section or an elapsed time from a previous stop of hot water supply. 4. The control means determines a total amount of combustion heat to be provided by continuous combustion according to information on a combustion state at the time of hot water supply at the time of stopping hot water supply, and continues combustion for a time during which the total amount of combustion heat is obtained. The hot water supply apparatus according to claim 2 or 3, wherein 5. The control means calculates a continuous burning time at a time of stopping hot water supply in accordance with information on a combustion state at the time of hot water supply, and continuously burns the continuous burning time with a predetermined amount of combustion heat per unit time. 3. The method according to claim 2, wherein
Or the hot water supply apparatus of 3. 6. The hot water supply apparatus according to claim 4, wherein the information on the combustion state at the time of hot water supply includes one or both of a heat quantity of combustion per unit time and a set time. 7. The combustion section has a plurality of combustion areas that can be independently controlled in combustion, and the information on the combustion state at the time of hot water supply is information on the number of combustion areas in the combustion state at the time of hot water supply. The hot water supply apparatus according to claim 4 or 5, wherein the control means calculates the total amount of combustion heat or the continuous combustion time corresponding to the number of the combustion regions at the time of stopping the hot water supply. 8. The hot water supply according to claim 4, wherein the control means determines the total combustion heat amount or the continuous combustion time during the continuous combustion according to the outside air temperature. apparatus. 9. The heat exchanger according to claim 9, wherein the pipe is a heat receiving pipe passing through a heat exchanging section.
A water supply pipe and a hot water supply pipe respectively connected to the inlet and the outlet of the heat receiving pipe, and a bypass pipe connected to the water supply pipe and the hot water supply pipe in parallel with the heat receiving pipe; The hot water supply apparatus according to any one of claims 4 to 8, wherein the total combustion calorie or the continuous combustion time during the continuous combustion is determined in accordance with the temperature of incoming water entering the hot water supply pipe via the hot water supply pipe.