JP3171979B2 - Circulating warm water heater - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circulating heat retaining type hot water supply apparatus, and more particularly, to sharing a flow rate sensor for detecting a circulating flow rate during circulating heat retention and a flow rate sensor for detecting hot water.
The present invention relates to a hot water supply device capable of accurately detecting even a small amount of tap water and quickly supplying hot water at a desired temperature.

[0002]

2. Description of the Related Art A circulation path is formed by connecting an end side of a hot water supply pipe and an inlet side of a heat exchanger with a return pipe, and a circulation pump provided in the return pipe or the like is operated to operate the circulation pump. While circulating hot and cold water, the temperature of the hot water in the circulation path is detected by a temperature sensor provided at an appropriate position in the circulation path, and if the detected hot water temperature is lower than the set temperature, heating is performed by a heat exchanger. When the temperature of the hot water supply is reached, the circulating heat retention type hot water supply device that keeps the temperature of the hot water in the circulation path at an appropriate temperature by stopping the heating and quickly discharges the appropriate temperature hot water from the hot water tap connected to the hot water supply pipe is a special feature. Fairness 3-28
No. 664.

In such a circulating heat retaining type hot water supply apparatus, it is necessary to switch from the circulating heat retaining operation state to the hot water supply operation state by detecting that hot water is supplied from the hot water tap. In order to detect the use of hot water taps, it is conceivable to provide a flow sensor between the hot water supply pipe and the hot water tap, but a signal line must be laid from the hot water heater body to the hot water tap. Is bad. Further, when a plurality of hot water taps are provided, a plurality of flow sensors are required corresponding to each hot water tap, which is not preferable. Therefore, a system in which a flow sensor is provided on the upstream side of the water supply line from the connection between the water supply line and the return line and the hot water tap is detected based on the output of the flow amount sensor has been put into practical use. Have been.

[0004]

On the other hand, in order to efficiently control the circulation heating, a flow rate sensor and a water temperature sensor are provided in the water inlet side pipe of the heat exchanger in the circulation path, and the circulation flow rate detected by each sensor is determined. When the configuration is such that the amount of heat required for heat retention and heating is calculated based on the incoming water temperature and the set temperature set by the temperature setting device or the like and the intermittent combustion cycle of the burner in the heat exchanger is controlled, the incoming water line Flow rate sensors are provided on the upstream side and the downstream side of the connection between the air flow and the return pipe, respectively.

Considering the use of a hot water tap, that is, detection of hot water using a flow sensor provided in the circulation path, the flow rate for judging hot water is a value larger than the circulating flow rate during the circulation warming operation. If the circulating pump is stopped to reduce power consumption and operation noise while heat insulation is not being performed, the tap should be used if the amount of hot water from the tap is small. Can no longer be detected. Further, since the piping lengths of the tapping line and the return line differ for each installation location, the circulation flow rate differs for each installation location even if the capacity of the circulation pump is constant. For this reason, unless the flow rate for judging hot water is set higher than the circulation flow rate when the pipe length is short, erroneous detection will occur, and it will be difficult to detect hot water with a small flow rate.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and a single flow sensor detects the flow rate during circulating heat retention, and reliably detects the use of a hot water tap even when a small amount of hot water is supplied. It is an object of the present invention to provide a circulating heat retaining type hot water supply device capable of switching to a hot water supply state. It is a second object of the present invention to provide a circulating heat retaining type hot water supply apparatus capable of detecting the use of a hot water tap with a predetermined amount of hot water, even if the circulating flow rate during circulating heat retaining varies depending on the pipe length.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a circulating heat retaining type hot water supply apparatus according to the present invention connects a middle part of a hot water supply pipe and a water supply pipe by a return pipe, and connects the hot water supply pipe with heat exchange. In a non-hot water supply state where a hot water tap connected to the hot water supply line is not used, a circulation pump is interposed between the hot water supply line and the return line to operate the circulation pump. By appropriately performing a circulating heat retaining operation of heating with a heat exchanger while circulating hot and cold water in a conduit, in a circulating heat retaining type hot water supply device configured to maintain a hot water temperature in a circulating conduit within a predetermined temperature range,
Provided with a hot water use detection means for determining the hot water from the hot-water tap on the basis of the output of the flow rate sensor provided at any position of the circulation pipe in excluding return line, the hot water use detection means, a circulating pump operating conditions In the case of, the output of the flow sensor
Exceeded the first flow rate value corresponding to the operation of the circulation pump.
Sometimes it is judged that the hot water supply is being used and the circulation is
When the pump is stopped, the output of the flow sensor
Output when the second flow rate value corresponding to the pump stoppage is exceeded.
It is characterized by judging that the hot water supply is being used .

The hot water supply use detecting means may be configured to set a first flow rate value to be determined as the hot water supply use state in the circulating pump operation state , based on the circulation flow rate during the circulation warming operation.

[0009]

[Function] By providing a flow rate sensor at an arbitrary position in the circulation line except the return line, the circulation flow rate during the operation of the circulation pump can be improved.
Both the flow rate of hot water when the circulation pump is stopped and the total flow rate of the circulation flow and the flow rate of hot water when the hot water tap is used during operation of the circulation pump can be detected. The hot water supply use detection means is a circulation pump
In the operating state, the output of the flow sensor is
When the first flow rate value corresponding to operation is exceeded, hot water is not supplied.
It is determined that the hot water supply is being used, and the circulation pump is stopped.
In the case of, when the output of the flow sensor
Hot water is being discharged when the corresponding second flow rate value is exceeded.
When the circulation pump is operating, it is determined that hot water is being used when a flow rate greater than the circulation flow rate (output of the flow rate sensor) is detected, and when the circulation pump is stopped, the predetermined flow rate is detected. Sometimes it can be determined that hot water is used. That is, regardless of the operating state of the circulation pump, even a small amount of hot water can be detected without fail.

In addition, by setting the hot water use determining flow rate corresponding to the circulation pump operation based on the circulation flow rate during the circulation pump operation , the amount of hot water from the hot water tap becomes a predetermined amount regardless of the magnitude of the circulation flow rate. At that point, the use of the hot water tap can be detected.

[0011]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is an overall configuration diagram of a circulating heat retaining type hot water supply apparatus according to the present invention. In the hot water supply apparatus with the hot water tap 2 opened, the hot water supply apparatus 1 heats the water supplied from the water supply pipe 3 with the heat exchanger 4 and supplies hot water from the hot water tap 2 through the hot water supply pipe 5. In addition, in a non-hot water supply state in which the hot water tap 2 is closed, the heat exchanger 4 is operated by operating the circulation pump 7 interposed in the return pipe 6 connecting the terminal side of the hot water supply pipe 5 and the water supply pipe 3. , Hot water supply line 5, return line 6, water supply line 3
The hot water in the circulation pipe 8 is heated while circulating the water in the circulation pipe 8 composed of the water supply pipe 3a downstream from the connection of the return pipe 6 and the water in the circulation pipe 8 is maintained at a predetermined temperature. It is configured as follows.

The controller 9 includes a temperature sensor 10 provided in a water supply line 3a downstream of a connection portion between the water supply line 3 and the return line 6, and signals 10a, 10a, 11a, the temperature setting switch 13 and the set temperature of the temperature setting device 13 are input, and the gas on-off valve 15 and the gas proportional valve 16
The operation of the fan 18 for supplying combustion air to the burner 17 and the operation of the circulation pump 7 are controlled.

FIG. 2 is a functional block diagram of the controller. The controller 9 includes a circulation heat retention control unit 21,
It comprises a combustion control means 22 and a hot water supply use detecting means 23.

The circulating heat-retaining control means 21 periodically monitors the setting state of the heat-retaining operation switch 12, and when the heat-retaining operation is requested, the hot water temperature T detected by the temperature sensor 10.
C is compared with the set temperature TS set by the temperature setting device 13. When the hot / cold water temperature TC is lower than the set temperature TS by a predetermined temperature or more, the heat control heating request 21a is issued to the combustion control means 2.
2, the circulation pump operation command 21b is output to operate the circulation pump 7, and when the hot and cold water temperature TC reaches the set temperature TS, the output of the heat retention heating request 21a and the circulation pump operation command 21b is stopped. When the hot water supply heating request 23 a is supplied from the hot water supply use detecting means 23, the circulation heat retention control means 21
a and the output of the circulation pump operation command 21b are stopped.

The combustion control means 22 includes a heat-retaining and heating request 21a.
And the proportional combustion control based on the hot water supply heating request 23a. When the heat-retention heating request 21a is given, the combustion control means 22 sets the set temperature T
The temperature difference between S and the hot / cold water temperature TC is multiplied by the flow rate Q detected by the flow rate sensor 11 to calculate the required heat amount at the time of circulating heat retention, and the ON time and the OFF time of the intermittent combustion are determined by referring to a table registered in advance. Then, the burner 17 is intermittently burned by controlling the operation of the fan 18 and the opening and closing of the gas on-off valve 15 with the gas proportional valve 16 kept at, for example, the minimum opening.

When the hot water supply heating request 23a is given, the combustion control means 22 drives the fan 18 and the on-off valve 15 to the combustion state, and detects the temperature difference between the set temperature TS and the hot water temperature TC by the flow rate sensor 11. The required heat quantity at the time of hot water supply is calculated by multiplying the flow rate Q at the time of hot water supply, and the opening of the gas proportional valve 16 is adjusted so as to generate the calculated required heat quantity. When the calculated required heat amount is equal to or less than the minimum heat amount in the proportional combustion control, the combustion control means 22 temporarily stops combustion or performs intermittent combustion control to prevent the tapping temperature from becoming too high at the time of small flow rate tapping. It is configured to prevent it.

The hot water use detection means 23 includes a hot water use determination means 24 and a hot water supply determination flow rate storage means 25 when the pump is stopped.
And hot water supply determination flow rate storage means 26 during pump operation, determination flow rate update means 27, and provisional circulation flow rate storage means 28.

When the circulation pump operation command 21b is not output, that is, when the circulation pump 7 is not operated, the hot water supply use judging means 24 stops the pump supplied from the hot water supply judgment flow rate storage means 25 when the pump is stopped. Is compared with the flow rate Q detected by the flow rate sensor 11, and the detected flow rate Q is determined as the hot water use determination flow rate QP.
If it exceeds off, it is determined that hot water is being used from the hot water tap 2 and a hot water heating request 23a is output. Further, in a state where the circulation pump operation command 21b is output, that is, in a state where the circulation pump 7 is operated, the hot water supply use determination flow rate QPon during the pump operation supplied from the hot water supply determination flow rate storage means 26 during the pump operation is equal to The flow rate Q detected by the flow rate sensor 11 is compared with the flow rate Q. If the detected flow rate Q exceeds the hot water use determining flow rate QPon, it is determined that hot water is being supplied from the hot water tap 2 and the hot water supply heating request 23a is determined. Is output.

Hot water supply determination flow rate storage means 25 when pump is stopped
Is configured using, for example, a ROM or the like, and flow rate data of, for example, about 1 to 1.5 liters per minute is registered in advance as a hot water supply determination flow rate when the pump is stopped. It should be noted that the hot water supply determination flow rate storage means 25 when the pump is stopped may use a digital switch or the like which can set numerical data, and may set the set value appropriately.

The provisional circulation flow rate storage means 28 stores, for example, RO
M, etc., and the circulation flow rate when the arrangement length of the hot water supply pipe line 5 and the return pipe line 6 is the shortest is registered in advance as a provisional circulation flow rate. This provisional circulation flow value is set according to the capacity of the circulation pump 7. In this embodiment, 4 minutes per minute
The value is about 5 liters.

Hot water supply determination flow rate storage means 26 during pump operation
Is configured using a RAM or the like, and the determined flow rate can be rewritten by the determined flow rate updating means 27. The determination flow updating means 27 adds the hot water supply determination flow QPoff when the pump is stopped stored in the hot water supply determination flow storage when the pump is stopped to the temporary circulation flow value stored in the temporary circulation flow storage means 28. The value is first written into the hot water supply determination flow rate storage means 26 during the pump operation.

Then, the judgment flow updating means 27 informs the circulation pump operation command 21b that the circulation warming operation is being performed.
, The flow rate detected by the flow rate sensor 11 is monitored, and when the detected flow rate Q falls within a predetermined fluctuation range over a predetermined time, an average flow rate at that time is calculated, and the calculated average flow rate is calculated. Then, a value obtained by adding the hot water supply judgment flow rate when the pump is stopped is written to the hot water supply judgment flow rate storage means 26 during the pump operation. Instead of adding the hot water supply determination flow rate QPoff when the pump is stopped, a preset flow rate value may be added.

As described above, since the flow rate for judging the use of hot water is made different depending on the operation state of the circulation pump 7, the circulation flow rate is detected using a single flow rate sensor 11, and Even if the amount of hot water from hot water tap 2 is small, its use can be reliably detected and hot water heating control can be performed. In addition, since the circulation flow rate is detected during the circulation warming operation and the hot water supply flow rate during the circulation pump operation is set based on the detected circulation flow rate, the flow rate during the circulation pump operation differs depending on the installation conditions of the water heater. However, since a predetermined amount of hot water is supplied from hot water tap 2, the use of hot water can be reliably detected.

In this embodiment, the flow rate sensor 11 is provided on the water inlet side of the heat exchanger 4, but the flow rate sensor 11 may be provided on the tapping line 5 side. Further, the configuration has been described in which a value obtained by adding a predetermined flow rate to the circulating flow rate is stored in the hot water supply use determination flow rate storage means 26 during the pump operation, but the circulating flow rate is stored. A configuration may be adopted in which it is determined that hot water is to be used when only a large flow rate is detected.

[0025]

As described above, in the circulation warming type hot water supply apparatus according to the first aspect, the flow rate sensor is provided at an arbitrary position in the circulation line except the return line. The hot water supply flow rate when the circulation pump is stopped, the total flow rate of the circulation flow when the hot water tap is used during the operation of the circulation pump and the total flow rate of the hot water flow can be detected. Since the flow rate value for judging the use of hot water was made different, it was judged that hot water was used when a flow rate larger than the circulating flow rate by a predetermined amount was detected during the operation of the circulation pump, and when the predetermined flow rate was detected when the circulation pump was stopped. It can be determined to be used. That is, irrespective of the operation state of the circulation pump, even a small amount of hot water can be reliably detected and switched to the hot water supply operation state.

Further, since the hot water supply is determined during the operation of the circulation pump based on the circulation flow rate during the operation of the circulation pump, the circulation flow rate differs due to the difference in the length of the hot water supply line and the return line. Also, when the amount of hot water from the hot water tap reaches a predetermined amount, the use of the hot water tap can be accurately detected.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a circulation type hot water supply apparatus according to the present invention.

FIG. 2 is a functional block diagram of a circulation type hot water supply apparatus according to the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 hot water supply device 2 hot water tap 3 hot water supply line 4 heat exchanger 5 hot water supply line 6 return line 7 circulation pump 8 circulation line 9 controller 11 flow sensor 23 hot water use detection means 24 hot water use judgment means 25 hot water supply when pump is stopped Determination flow storage means 26 Hot water supply determination flow storage means during pump operation 27 Determination flow update means

────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Tetsuro Takada 43-1, Uozakihama-cho, Higashinada-ku, Kobe-shi, Hyogo Prefecture Inside Japan Yupro Corporation (72) Inventor Shinji Miura 43-1, Uozakihama-cho, Higashinada-ku, Kobe-shi, Hyogo Inside Nippon Yupro Co., Ltd. (72) Inventor Kiyotaka Nakano 43-1 Uozakihama-cho, Higashinada-ku, Kobe City, Hyogo Prefecture Within Nippon Yupro Co., Ltd. (72) Inventor Hikaru Hiragun 43-1 Uozakihama-cho, Higashinada-ku, Kobe City, Hyogo Prefecture (56) References JP-A-61-110838 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) F24H 1/10 302

Claims (2)

(57) [Claims] 1. An intermediate portion of a hot water supply line and a water supply line are connected by a return line, and an annular line is formed by the water supply line, the heat exchanger, the hot water supply line, and the return line. In a non-hot-water supply state in which the connected hot-water tap is not used, a circulation heat retention operation of heating with a heat exchanger while circulating hot and cold water in the circulation pipeline by operating a circulation pump provided in the return pipeline is appropriately performed. Thus, in the circulating heat retaining type hot water supply device in which the temperature of the hot water in the circulation pipeline is maintained within a predetermined temperature range, hot water is supplied based on the output of a flow rate sensor provided at an arbitrary position in the circulation pipeline except for the return pipeline. Hot water supply use detection means for judging hot water from the tap is provided, and the hot water supply use detection means is provided with the flow rate sensor in the case of the circulating pump operating state.
Is the first flow value corresponding to the operation of the circulation pump.
It is determined that hot water is being used when hot water is supplied
However, when the circulation pump is stopped, the flow rate
Is the second flow value corresponding to the time when the circulation pump is stopped.
It is determined that hot water is being used when hot water is supplied
A circulating warm water heater. 2. The hot-water supply use detecting means sets a circulation pump operation state based on a circulation flow rate during the circulation warming operation .
Kicking circulating heat insulating type hot water supply apparatus according to claim 1, characterized by being configured to set the first flow rate value to determine that the hot water use.