JP2015183864A - Hot water supply device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hot water supply device capable of accurately discharging hot water of target temperature even if hot water of high temperature shows a rapid variation in temperature.SOLUTION: This invention relates a hot water supply device in which cold water of low temperature got from a feeding pipe 12 and hot water of high temperature got from a primary heat exchanger 8 for supplying hot water are mixed to each other to generate mixed hot water to be supplied as hot water. There are provided temperature sensors 17 to 19 for detecting each of temperatures of low temperature water, high temperature water and these mixed hot water. A control part 6 controls a mixing ratio of high temperature water and low temperature water on the basis of temperature data of the temperature sensors so as to control temperature specifying a temperature of the mixed hot water to a target temperature, the control part 6 detects the temperature data of high temperature water under a specified period and monitors it and when its variation wave-form is kept at its normal state, the detected temperature data is applied as a temperature of high temperature hot water and in turn when its variation wave-form is in a low frequency range, increasing or decreasing of the temperature data is amplified and when it is in a high frequency range, increasing or decreasing of the temperature data is reduced to perform a correcting processing and executes the prescribed temperature control.

Description

  The present invention relates to a hot water supply apparatus, and more particularly, to a hot water supply apparatus that mixes low-temperature water and high-temperature water to generate hot water at a target temperature to supply hot water.

  Conventionally, in a hot water supply apparatus that supplies hot water to hot water taps such as currants and showers, normal temperature low temperature water supplied from a water source such as city water and hot water heated by a heat exchanger are mixed. Hot water having a target temperature (for example, hot water set temperature) is generated, and the generated mixed hot water is supplied to the hot water tap.

  In such a hot water supply apparatus, a temperature sensor for low temperature water (for example, a water temperature sensor) for detecting the temperature of low temperature water and a temperature sensor for high temperature water (for example, a can body temperature sensor) for detecting the temperature of high temperature water. And a temperature sensor for mixed hot water (for example, a tapping temperature sensor) that detects the temperature of the mixed hot water, and the controller of the hot water supply device is based on the temperature data detected by each of these temperature sensors, The mixing ratio of the low temperature water and the high temperature water is adjusted to generate hot water having a target temperature (see, for example, Patent Document 1).

JP 2006-177623 A

  However, such a conventional hot water supply apparatus has the following problems, and improvements have been desired.

  That is, in the conventional hot water supply apparatus, a thermistor is generally used as a temperature sensor for detecting each temperature of these low temperature water, high temperature water, and mixed hot water, but a can thermistor for detecting the temperature of high temperature water is a gas burner. Because it is provided on the outlet (outlet) side of the heat exchanger that is heated by heating means such as hot water (hot water) to be detected compared to the temperature sensor for detecting the temperature of low-temperature water or mixed hot water Temperature fluctuation is frequent and large.

  Therefore, the can body thermistor provided on the outlet side of the heat exchanger (for example, the primary heat exchanger in the latent heat recovery type hot water supply device) in which this tendency appears more conspicuously has a delay in response due to the heat capacity of the thermistor as The actual temperature of the hot water (actual temperature) could not be detected accurately, which could hinder the establishment of the temperature of the mixed hot water.

  FIG. 6 shows an example of the correlation between the temperature fluctuation of the high temperature water and the detected temperature of the thermistor. As shown in FIG. 6, when the temperature (actual temperature) of the high-temperature water rises rapidly, then falls sharply and then starts to rise again, the detected temperature of the thermistor rises behind the actual temperature. Without detecting the maximum actual temperature (80 ° C in the illustrated example), the temperature starts falling after the actual temperature, and rises after the actual temperature without detecting the minimum actual temperature (40 ° C in the illustrated example). . When the temperature fluctuates up and down in this way, a temperature sensor such as a thermistor that has a delay in temperature detection has a deviation from the actual temperature in the detected temperature value as well as the detection delay. .

  The present invention has been made in view of such conventional problems, and an object of the present invention is to provide a hot water supply apparatus that can accurately discharge hot water at a target temperature even when there is a rapid temperature fluctuation in high temperature water. It is to provide.

  In order to achieve the above object, a hot water supply apparatus according to the present invention is a hot water supply apparatus that mixes low-temperature water and high-temperature water to supply hot water, and detects each temperature of low-temperature water, high-temperature water, and mixed hot water thereof. Hot water supply provided with a temperature sensor and a control unit for controlling the mixing ratio of the hot water and the low temperature water to establish the temperature of the mixed hot water as a target temperature based on each temperature data detected by these temperature sensors In the apparatus, the control unit detects the temperature data of the high-temperature water at a predetermined cycle, monitors fluctuations in the detected temperature data, and when the fluctuation waveform is in a steady state, the detected temperature data is When the fluctuation waveform is in a predetermined low frequency region, the increase / decrease in temperature data is amplified, and when the fluctuation waveform is in a predetermined high frequency region, correction processing is performed to reduce the increase / decrease in temperature data. And executes the temperature control Te.

And as the suitable embodiment, the said correction process is performed using the following numerical formula, It is characterized by the above-mentioned.
Θ _hi (n) = {a ₀ · θ _Th (n) + a ₁ · θ _Th (n−1) +... + A _N−1 · θ _Th (n−N)} / (a ₀ + a ₁ +... A _N-1 )
Where θ _hi (n) is the temperature of the high-temperature water for temperature control, θ _Th (n) is the latest detected temperature of the temperature sensor for high-temperature water, and θ _Th (n−1) is the temperature sensor for high-temperature water. Previously detected temperature, θ _Th (n−N): detected temperature N times before the temperature sensor for high temperature water, a _{0 to} a _N-1 : coefficient

  That is, in the hot water supply apparatus according to the present invention, when the temperature control of the mixed hot water is performed, the control unit detects the temperature data of the high temperature water at a predetermined cycle, and when the detected temperature data is in a steady state without fluctuation. The temperature control is performed using the detected temperature data as it is as the temperature of the high-temperature water. On the other hand, when the detected temperature data is fluctuated and the fluctuation waveform is in a predetermined low frequency region, the increase or decrease in the temperature data is amplified, and when the fluctuation waveform is in the predetermined high frequency region, the temperature data is fluctuated. By performing the correction process for reducing the temperature, the temperature control for generating the mixed hot water is performed by bringing the temperature data of the hot water detected by the temperature sensor closer to the actual temperature of the hot water. Thereby, the hot water supply apparatus which can discharge hot water of the mixed temperature of target temperature correctly can be provided now.

  As a preferred embodiment of the present invention, the temperature sensor for detecting the temperature of the high-temperature water is provided on the tapping side of the sensible heat recovery type heat exchanger that generates the high-temperature water. And

  That is, in this embodiment, since the temperature sensor for detecting the temperature of the high temperature water is provided on the tapping side of the sensible heat recovery type heat exchanger that generates the high temperature water, the length of the water pipe arranged in the heat exchanger is provided. The temperature of the mixed hot water can be accurately controlled even in a hot water supply apparatus that is short and has a high temperature fluctuation.

  According to the present invention, when performing temperature control for mixing hot water and low temperature water to generate mixed hot water having a target temperature, the control unit detects the temperature data of the high temperature water at a predetermined cycle, and the detected temperature data When the fluctuation waveform is in a steady state, the detected temperature data is used as the temperature of the high-temperature water, and when the fluctuation waveform is in a predetermined low frequency region, the increase / decrease in the temperature data is amplified, while the fluctuation waveform is in the predetermined high frequency region. Since the correction process for reducing the increase / decrease in the temperature data is performed, the temperature of the mixed hot water can be established accurately and accurately.

It is a block diagram which shows an example of schematic structure of the hot water supply apparatus which concerns on this invention. It is explanatory drawing which shows the correlation of the actual temperature of high temperature water, and the detection temperature of a temperature sensor, Fig.2 (a) shows an example of the actual temperature with respect to the frequency of the temperature fluctuation waveform, and the detection temperature of a temperature sensor, FIG. FIG. 2B shows the characteristic of FIG. 2A as a change in the detected temperature with respect to the actual temperature. FIG. 3A is an explanatory diagram showing a model of a correction process for the detected temperature of the temperature sensor. FIG. 3A shows the characteristics of the pulse transfer function of the correction process, and correction rate = actual temperature / detected temperature (FIG. 2) in the frequency range to be restored. FIG. 3B is a characteristic of the combined transfer function, and shows detected temperature × correction rate = detected temperature × (actual temperature / detected temperature) = actual temperature. An example of the coefficient used for the correction process of the temperature detected by the temperature sensor is shown. It is explanatory drawing which shows the relationship between the temperature detected by a temperature sensor, and the temperature data after correction | amendment. It is a correlation diagram which shows an example of the correlation of the temperature fluctuation of high temperature water, and the detection temperature of a thermistor.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows an example of a hot water supply apparatus according to the present invention. The hot water supply apparatus 1 shown in FIG. 1 is a so-called latent heat recovery type gas hot water supply apparatus, and is used for a hot water supply function for supplying hot water to hot water taps such as currants and showers, and a hot water heating apparatus such as a floor heating panel and a fan convector. A hot water heating function for supplying hot water as a heat medium and a bath function for performing hot water filling and bathing in a bathtub are provided.

  Specifically, the hot water supply device 1 includes a combustion can body 2, a hot water supply pipe (hot water supply circuit) 3, a heating pipe (heating circuit) 4, and a bath reheating pipe (bath circuit) 5. And the control part 6 which controls each part of the hot water supply apparatus 1 is provided as a main part.

  The combustion can body 2 is a metal container that accommodates the burner 7. The combustion can body 2 includes the burner 7, a primary heat exchanger 8 for hot water supply, and a secondary heat exchanger for hot water supply. 9, a primary heat exchanger 10 for heating, and a secondary heat exchanger 11 for heating are accommodated. In addition, 2a is an exhaust port for discharging the combustion exhaust gas of the burner 7.

  The burner 7 is a heating means that heats the heat exchangers 8 to 11 for hot water supply and heating, and is composed of a gas burner that uses city gas or propane gas as fuel. Although the detailed structure of the burner 7 is not shown in FIG. 1, the burner 7 includes a plurality of combustion tubes, and the control unit 6 controls the combustion state of the combustion tubes ( By controlling the number of combustion and the fuel supply amount), the hot water supply side and heating side burners can be burned independently.

  The primary heat exchangers 8 and 10 for hot water supply and heating are heat exchangers (for example, fin-tube type heat exchangers) that perform gas-liquid heat exchange with the combustion gas of the burner 7, and are in the immediate vicinity of the burner 7. It is arranged above. These primary heat exchangers 8 and 10 for hot water supply and heating are constituted by sensible heat recovery type heat exchangers that perform heat exchange without lowering the temperature of the combustion gas of the burner 7 to below the boiling point of water. In the present embodiment, in the primary heat exchanger 8 for hot water supply, only one stage of water pipes through which the low-temperature water preheated by the secondary heat exchanger 9 passes is arranged in the vertical direction. That is, in a typical primary heat exchanger for hot water supply, the water pipes are arranged in two or more stages in the vertical direction so that the heat of the combustion gas can be efficiently recovered (arranged so that the length of the water pipe becomes long). However, in the hot water supply apparatus 1 of this embodiment, in order to reduce the manufacturing cost of the heat exchanger, the water pipes of the primary heat exchanger 8 for hot water supply are arranged in only one stage in the vertical direction (arranged so that the length of the water pipe is shortened). ) Therefore, in the hot water supply apparatus 1 shown in the present embodiment, the hot water discharged from the primary heat exchanger 8 for hot water supply is accompanied by a rapid temperature change.

  Each of the secondary heat exchangers 9 and 11 for hot water supply and heating uses heat exchange that performs gas-liquid heat exchange with the combustion exhaust gas after heat exchange is performed in the primary heat exchangers 8 and 10 for hot water supply and heating. It is a heat exchanger (for example, a spiral tube type heat exchanger), and is disposed above the primary heat exchangers 8 and 10 for hot water supply and heating. These hot water supply and heating secondary heat exchangers 9 and 11 are both latent heat recovery types that perform heat exchange by lowering the temperature of the combustion exhaust gas after heat exchange in the primary heat exchangers 8 and 10 below the boiling point of water. It consists of a heat exchanger. For this reason, the secondary heat exchangers 9 and 11 are provided with drain drain means (not shown) for discharging condensed water (drain) generated along with heat exchange.

  The hot water supply circuit 3 is a water flow path for supplying hot water to a hot water tap (not shown), one end of which is connected to a water source (not shown) such as a water supply, and the other end is input to the secondary heat exchanger 9 for hot water supply. The main part is composed of a water inlet pipe 12 connected to the side, and a hot water outlet pipe 13 having one end connected to the hot water outlet side of the primary heat exchanger 8 for hot water supply and the other end connected to a hot water tap. The hot water outlet side of the secondary heat exchanger 9 is connected to the incoming water side of the primary heat exchanger 8 for hot water supply. That is, the hot water supply circuit 3 can supply normal temperature water (low temperature water) supplied from the water inlet pipe 12 to the hot water outlet pipe 13 from the secondary heat exchanger 9 for hot water supply through the primary heat exchanger 8 for hot water supply. It is configured.

  A bypass pipe 15 is provided between the water inlet pipe 12 and the hot water outlet pipe 13 for connecting the water inlet pipe 12 and the hot water outlet pipe 13 via a distribution valve 14 provided in the water inlet pipe 12. The distribution valve 14 is a water amount adjustment valve for adjusting the amount of low-temperature water flowing into the hot water discharge pipe 13 via the bypass pipe 15, and the control unit 6 controls the operation of the distribution valve 14 to increase the temperature. The mixing ratio of water and low-temperature water can be adjusted (controlled).

  Further, the hot water supply circuit 3 supplies an incoming water amount sensor 16 for detecting the amount of low-temperature water (incoming water amount) supplied to the secondary heat exchanger 9 for hot water supply and a secondary heat exchanger 9 for hot water supply. Water temperature sensor 17 for detecting the temperature of the low-temperature water (water temperature), can body temperature sensor 18 for detecting the temperature of the hot water discharged from the primary heat exchanger 8 for hot water supply (can body temperature) , A hot water temperature sensor 19 for detecting the temperature (hot water temperature) of the mixed hot water discharged from the hot water pipe 13 (hot water mixed with the low-temperature water supplied via the bypass pipe 15), and mixed hot water discharged from the hot water pipe 13 The control unit 6 controls the water amount data (data of the incoming water amount) detected by the various sensors 16, 17, 18, and 19 and the temperature. Data (incoming water temperature, hot water temperature of can body and The amount of low-temperature water (mixing ratio) to be supplied to the hot water discharge pipe 13 via the distribution valve 14 is adjusted so that the hot water temperature becomes the hot water supply set temperature (target temperature) based on the hot water temperature data). It is configured.

  The heating circuit 4 is a water flow path for supplying hot water, which is a heating medium, to a low-temperature heating terminal such as a floor heating panel and a high-temperature heating terminal such as a fan convector, and one end is a high-temperature terminal (not shown). The heating high-temperature forward pipe 21 is connected to the hot water input side, and the other end is connected to the hot water outlet side of the primary heat exchanger 10 for heating, and one end is connected to the hot water input side of a low-temperature heating terminal (not shown). The other end is connected to the inlet side of the heating primary heat exchanger 22 and the other end is connected to the hot water output side of the high temperature heating terminal and the low temperature heating terminal (the hot water outlet after heat exchange). A heating return pipe 23 whose other end is connected to the water inlet side of the secondary heat exchanger 11 for heating, one end is connected to the hot water outlet side of the secondary heat exchanger 11 for heating, and the other end is an expansion tank. 25 and a heating circulation pump 26 are connected to the heating low temperature outlet pipe 22. Was the heating circulation pipe 24 is equipped as the main part.

  Here, in the expansion tank 25, the heating circulation pipe 24 a connected to the hot water outlet side of the secondary heat exchanger 11 for heating is connected to the lower end portion of the expansion tank 25, and heating connected to the heating low temperature forward pipe 22. The circulation pipe 24 b is connected to the lower layer portion of the expansion tank 25 so that low temperature hot water can be taken out from the lower layer region of the expansion tank 25. In addition, the upper end portion of the expansion tank 25 is connected to a water replenishing pipe 27 having one end connected to the water inlet pipe 12, and by opening the water replenishing on-off valve 28 provided in the water replenishing pipe 27, The expansion tank 25 is configured to be refilled. The expansion tank 25 is provided with a water level detection means (not shown). When the water level detected by the water level detection means falls below a predetermined water level, the controller 6 opens the on-off valve 28 to the expansion tank 25. It is designed to replenish water.

  And in this heating circuit 4, the high temperature hot water discharged from the primary heat exchanger 10 for heating is supplied to the high temperature heating terminal via the heating high temperature outgoing pipe 21, and after the heat exchange (heat radiation) at the heating high temperature terminal Hot water is supplied to the secondary heat exchanger 11 for heating via the heating return pipe 23. Further, the heat-dissipated hot water supplied to the heating secondary heat exchanger 11 is heated by the latent heat recovery in the heating secondary heat exchanger 11, and then heated through the heating circulation pipe 24a to the expansion tank 25. Supplied to the lower layer region. And the low temperature warm water stored in the lower layer area of the expansion tank 25 is joined to the heating low temperature forward pipe 22 via the heating circulation pipe 24b, and here, to the low temperature heating terminal and the primary heat exchanger 10 for heating. Supplied. That is, a part of the low-temperature hot water taken out from the expansion tank 25 is supplied to the low-temperature heating terminal, and after being radiated at the low-temperature heating terminal, supplied to the secondary heat exchanger 11 for heating via the heating return pipe 23, The other part is supplied to the primary heat exchanger 10 for heating, and the primary heat exchanger 10 for heating becomes high-temperature hot water and is supplied to the high-temperature heating terminal. The hot water is circulated in the heating circuit 4 by the control unit 6 operating the circulation pump 26.

  And in this heating circuit 4, the heating high temperature sensor 29 which detects the temperature of the hot water supplied to the high temperature heating terminal on the tapping side of the primary heat exchanger 10 for heating, and the low temperature terminal at the lower end of the expansion tank 25 A heating low temperature sensor 30 that detects the temperature of the hot water to be supplied is provided, and the control unit 6 performs primary and secondary heat exchange for heating based on temperature data detected by the temperature sensors 29 and 30. Combustion control of the burner 7 for heating the vessels 10 and 11 is performed.

  The bath circuit 5 is a water passage mainly provided for reheating the bath, and serves as a heat medium on the primary side of the liquid-liquid heat exchanger (bath heat exchanger) 31 for reheating the bath. A reheating hot water pipe 32 for supplying hot water, one end is connected to the secondary water inlet side of the bath heat exchanger 31, and the other end is a bathtub (not shown). The return pipe 33 connected to the hot water inlet (not shown) of the adapter fitting that discharges hot water to the water, and one end connected to the secondary hot water side of the bath heat exchanger 31 and the other end The main part is provided with a bathtub 34 (specifically, a warm pipe discharge port (not shown) of the adapter fitting) connected to a bathtub.

  The bath return pipe 33 of the bath circuit 5 has a bath circulation pump 35 for circulating the hot water sucked from the bathtub to the bath tube 34 and the temperature of the hot water supplied to the bath heat exchanger 31 ( A bath return temperature sensor 36 for detecting the bath return temperature) and a bath temperature sensor 37 for detecting the temperature of the warm water supplied from the bath heat exchanger 31 to the bath pipe 34 (bath temperature) are provided. Based on the temperature data detected by these temperature sensors 36 and 37, the control unit 6 is for heating so that the temperature of the hot water in the bathtub (that is, the bath return temperature) becomes the bath set temperature (the bath target temperature). Combustion control of the burner 7 that heats the primary heat exchanger 10 and the secondary heat exchanger 11 is performed.

  In addition, the bath circuit 5 has a pouring pipe 38 having one end connected to the hot water pipe 13 and the other end connected to the return pipe 33 as a water passage for pouring water into the bathtub (dropping warm water). The pouring pipe 38 is provided with an on-off valve 39 for pouring. That is, when the control unit 6 opens the pouring open / close valve 39, hot water discharged from the hot water discharge pipe 13 is dropped into the bathtub through the return pipe 33.

  The control unit 6 is a control device for controlling each part of the hot water supply device 1 and includes a microcomputer (not shown). Based on a control program provided in the microcomputer, the hot water supply function, the hot water heating function, and the bath Functions are realized. The control unit 6 is provided with a remote control device (remote controller) (not shown), and the remote controller can set and change the hot water supply set temperature and bath set temperature.

  Next, temperature establishment (temperature control) of hot water for hot water supply (mixed hot water) in the hot water supply apparatus 1 configured as described above will be described with reference to FIGS.

  As described above, in the hot water supply apparatus 1 shown in the present embodiment, since the heat exchanger having a short water pipe length is used as the primary heat exchanger 8 for hot water supply, the hot water is discharged from the primary heat exchanger 8 for hot water supply. The hot water that is produced may be accompanied by a rapid temperature change. Therefore, if a thermistor having a response delay due to heat capacity is used as the can temperature sensor 18 that detects the temperature of the high-temperature water, the controller 6 may not be able to accurately detect the temperature of the high-temperature water.

  Therefore, in the hot water supply apparatus 1 shown in the present embodiment, the control unit 6 detects the temperature data of the can body temperature sensor 18 at a predetermined cycle (for example, a cycle of 100 mS) set in advance, and detects the fluctuation of the detected temperature data. When the fluctuation waveform is monitored and the fluctuation waveform is in a steady state (that is, there is no fluctuation in the temperature data), the temperature of the mixed hot water is controlled using the temperature data detected by the can body temperature sensor 18 as the temperature of the high temperature water. When the fluctuation waveform of the temperature data detected by the temperature sensor 18 has a fluctuation, if the fluctuation waveform is in a predetermined low frequency region, a correction process for amplifying the increase / decrease in the temperature data detected by the can temperature sensor 18 On the other hand, when the fluctuation waveform is in a predetermined high-frequency region, a correction process is performed to reduce the increase or decrease in the temperature data detected by the can body temperature sensor 18, and the mixed hot water It is configured to control the temperature.

  That is, when there is no change in the fluctuation waveform of the temperature data of the can body temperature sensor 18 detected at a predetermined cycle and the value of the temperature data is substantially constant (when in a steady state), there is no response delay of the can body temperature sensor 18. Therefore, the temperature control of the mixed hot water can be performed using the detected temperature data as it is as the temperature of the high temperature water. On the other hand, when the temperature data of the can body temperature sensor 18 detected at a predetermined cycle varies, the response delay of the can body temperature sensor 18 becomes a problem.

  FIG. 2 shows the actual temperature of high-temperature water with respect to the frequency of the temperature fluctuation waveform (or the temperature data of a temperature sensor that can detect a temperature close to the actual temperature such as a thermocouple) and the can body temperature sensor 18. The correlation of the detected temperature (temperature data) of the thermistor is shown. Specifically, FIG. 2 shows these two data in the same period with intensity for each frequency by discrete Fourier transform or the like, and when the frequency of the temperature fluctuation waveform becomes higher as shown in FIG. Thermistor response delay increases. FIG. 2B shows the characteristics shown in FIG. 2A as changes in the detected temperature with respect to the actual temperature.

  Thus, the response delay of the thermistor detection temperature increases as the frequency of the temperature fluctuation waveform increases, because the response of the thermistor has a characteristic shown in the following Equation 1 as a primary delay including a dead time. .

  A function representing the ratio of detected temperature / actual temperature shown in FIG.

Therefore, in the present embodiment, the control unit 6 performs processing on the detected temperature θ _Th (n) of the thermistor, and gives the pulse transfer function H (z) of the processing to the characteristic as shown in the following Expression 3. The composite transfer function G _Th (s) H (z) is given a characteristic as shown in Equation 4.

  That is, as shown in FIG. 3A, the detected temperature of the thermistor before processing is to be processed as noise when the frequency of the temperature fluctuation waveform becomes higher than a predetermined threshold value, and is due to response delay. The frequency range in which the deviation of the detected temperature is to be restored is a fixed frequency range (the range indicated by “frequency range to be restored” in FIG. 3A). For this reason, in the present embodiment, the data of the frequency region to be restored is restored as shown in FIG. 3B by the correction process of the control unit 6.

  Specifically, in the present embodiment, the control unit 6 performs a correction process on the temperature data detected by the can body temperature sensor 18 using Equation 5 below.

However, in the above formula 5, θ _hi (n) is the temperature of the high temperature water for temperature control, θ _Th (n) is the detected temperature nearest to the temperature sensor for high temperature water, and θ _Th (n−1) is the high temperature water. The previous detected temperature of the temperature sensor for water, θ _Th (n−N) represents the detected temperature N times before the temperature sensor for high temperature water, and a _{0 to} a _N−1 represent coefficients.

  The coefficient a is set based on experience values obtained by experiments for each model of the hot water supply device 1. FIG. 4 shows an example of the coefficient a, and the coefficient a has a general relationship as shown in FIG.

  Therefore, a correction example of temperature data using Formula 5 is shown. Here, when the control unit 6 corrects the detected temperature of the can body thermistor 18 using the current data and the past nine data (N = 10), for example, the control unit 6 may Calculation is performed to correct the temperature data detected by the can body thermistor 18. In this example, the current data and the past nine data are used, but the value of N in Equation 5 can be changed as appropriate.

  FIG. 5 shows the relationship between the temperature detected by the can body temperature sensor 18 and the temperature data corrected by the control unit 6. As shown in FIG. 5, the corrected temperature data is a value closer to the actual temperature because the temperature deviation due to the response delay of the can body temperature sensor 18 is reduced.

  Thus, in the hot water supply apparatus 1 shown in this embodiment, the control unit 6 corrects the temperature data detected by the temperature sensor (can temperature sensor 18) that detects the temperature of the high-temperature water, and establishes the temperature of the mixed hot water. Therefore, the mixed hot water having the target temperature can be accurately discharged as the mixed hot water for hot water supply.

  The above-described embodiment shows a preferred embodiment of the present invention, and the present invention is not limited to this, and various design changes can be made within the scope of the invention.

  For example, in the above-described embodiment, the case where the temperature data of the hot water discharged from the primary heat exchanger 8 is corrected in the latent heat recovery type gas hot water supply apparatus of the present invention has been described. The present invention can be applied not only to the hot water supply apparatus but also to other forms of hot water supply apparatus. That is, the present invention can be applied to any hot water supply device in which the temperature fluctuation of high temperature water is severe.

  Moreover, although the case where the thermistor was used as the can body temperature sensor 18 was shown in embodiment mentioned above, if it is a temperature sensor with a response delay with respect to actual temperature, this invention is applied also to temperature sensors other than a thermistor. Is possible.

  Moreover, although the case where this invention was applied to the hot water supply apparatus provided with the hot water heating function and the bath function in addition to the hot water supply function was shown in embodiment mentioned above, this hot water supply apparatus which does not have a hot water heating function and a bath function is also this. The invention is applicable.

DESCRIPTION OF SYMBOLS 1 Hot water supply apparatus 2 Combustion can 3 Hot water supply circuit 4 Heating circuit 5 Bath circuit 6 Control part 7 Burner 8 Primary heat exchanger 9 for hot water supply Secondary heat exchanger 10 for hot water supply Primary heat exchanger 11 for heating Secondary heat exchanger 12 Inlet pipe 13 Outlet pipe 14 Distribution valve 15 Bypass pipe 16 Incoming water amount sensor 17 Incoming water temperature sensor (temperature sensor for low temperature water)
18 Can body temperature sensor (temperature sensor for high temperature water)
19 Hot water temperature sensor (mixed hot water temperature sensor)
20 Hot water outlet adjustment valve 21 Heating high temperature outgoing pipe 22 Heating low temperature outgoing pipe 23 Heating return pipe 25 Expansion tank 26 Heating circulation pump 31 Bath heat exchanger 32 Reheating hot water pipe 33 Bath return pipe 34 Bath outgoing pipe 35 Bath use Circulation pump

Claims (3)

A hot water supply device that mixes low temperature water and high temperature water to supply hot water,
The temperature sensor for detecting the temperature of the low temperature water, the high temperature water and the mixed hot water, and the temperature of the mixed hot water by controlling the mixing ratio of the high temperature water and the low temperature water based on the temperature data detected by these temperature sensors. In a hot water supply apparatus equipped with a control unit that performs temperature control to establish a target temperature as
The control unit detects the temperature data of the high temperature water at a predetermined cycle, monitors the fluctuation of the detected temperature data, and when the fluctuation waveform is in a steady state, the detected temperature data is set as the temperature of the high temperature water. When the fluctuation waveform is in a predetermined low frequency region, the temperature data is increased or decreased. On the other hand, when the fluctuation waveform is in a predetermined high frequency region, the temperature control is performed by performing a correction process to reduce the increase or decrease in temperature data. A hot water supply apparatus characterized by the above. The hot water supply apparatus according to claim 1, wherein the correction process is performed using the following mathematical formula.
Θ _hi (n) = {a ₀ · θ _Th (n) + a ₁ · θ _Th (n−1) +... + A _N−1 · θ _Th (n−N)} / (a ₀ + a ₁ +... A _N-1 )
Where θ _hi (n) is the temperature of the high-temperature water for temperature control, θ _Th (n) is the latest detected temperature of the temperature sensor for high-temperature water, and θ _Th (n−1) is the temperature sensor for high-temperature water. Previously detected temperature, θ _Th (n−N): detected temperature N times before the temperature sensor for high temperature water, a _{0 to} a _N-1 : coefficient   3. The hot water supply apparatus according to claim 1, wherein a temperature sensor that detects a temperature of the high temperature water is provided on a tapping side of a sensible heat recovery type heat exchanger that generates the high temperature water.

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