JP2990861B2 - 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 one-can-two-channel water heater mainly used in homes, which uses oil or gas as a heat source.

[0002]

2. Description of the Related Art As shown in FIG. 2, a conventional one-can, two-channel water heater has a heating burner 1 capable of varying the amount of combustion, a flow rate detecting device 3, an incoming water temperature detecting device 4, and a combustion heat of the heating burner. A hot water supply circuit composed of a hot water supply heat transfer tube 5 and a hot water temperature detector 6 for transferring heat, a bath circulation circuit composed of a bath water temperature detection device 7, a circulation pump 8, and a bath heat transfer tube 9; The heat transfer tube 5 and the bath heat transfer tube 9 share a heat absorbing fin 12 to form a heat exchanger 13.

[0003] In the case of the hot water supply operation and the simultaneous operation of hot water supply and bath heating, the combustion amount control starts with the temperature set value and the combustion amount calculated by the flow rate detecting device 3 and the incoming water temperature detecting device 4. Then, the combustion amount is corrected and controlled so that the hot water temperature becomes the set value. At this time, even if the hot water temperature does not reach the set value even if the combustion amount is increased to the combustible upper limit, the hot water supply operation and the bath heating operation are performed simultaneously.

[0004]

However, in the conventional configuration described above, in the case of simultaneous operation of hot water supply and bath heating as shown in FIG. 4, since the amount of heat is naturally insufficient at the start of operation, the amount of combustion is corrected and controlled in the increasing direction. In the operation, an operation delay occurs because the result of the difference between the value detected by the tapping water temperature detector 6 and the temperature set value is subjected to correction control using the result as an information source. Also, if the correction is suddenly made, the correction value becomes too large, the hot water temperature rises above the set value, and so-called overshoot occurs, so that the correction is added little by little. Therefore, the change in the amount of combustion becomes slow, and the temperature of the hot water during that time drops temporarily. Conversely, when only the bath heating operation is stopped from the simultaneous operation state, there is a problem that the hot water temperature temporarily rises for the same reason as described above.

[0005] Further, if the hot water temperature does not reach the set value even if the temperature reaches the combustible upper limit, the hot water supply operation and the bath heating operation are performed at the same time. Was.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a hot water supply apparatus which prevents a change in hot water temperature even when a hot water supply operation and a bath heating operation are performed at the same time and has a high usability. is there.

[0007]

SUMMARY OF THE INVENTION In order to achieve the above objects, the present invention provides a heating burner capable of varying the amount of combustion, a flow rate detecting device, an incoming water temperature detecting device, and a hot water supply transfer device for transferring the combustion heat of the heating burner. A hot water supply circuit composed of a heat pipe and a tap water temperature detection device, a bath circulation circuit composed of a bath water temperature detection device, a flow switch, a circulation pump, and a heat transfer tube for a bath, and a heat transfer tube for the hot water supply and a heat transfer tube for a bath. A heat exchanger configured to share heat-absorbing fins, and a control device for controlling the burner combustion rate
The control device starts combustion at a value calculated by the flow rate detection device and the incoming water temperature detection device during the hot water supply alone operation, and performs the hot water supply alone operation during the simultaneous hot water supply and bath heating operation.
Regardless of the combustion amount variable range
Set the value to the maximum and set the value for bath heating
A value obtained by adding a required constant value, and at least the hot water supply alone
Start combustion at a value larger than the operation , and
Changed from simultaneous operation to simultaneous operation to independent operation
The change of combustion amount at the time should be done instantaneously
In addition, when the combustion amount of the burner exceeds the combustible upper limit value, the bath heating operation is stopped .

[0008]

According to the present invention, there is provided a hot water supply apparatus having a high usability, which prevents fluctuations in hot water supply temperature even when a hot water supply operation and a bath heating operation are performed simultaneously.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG. The same components as those in the related art are denoted by the same reference numerals.

In FIG. 1, reference numeral 1 denotes a heating burner, and the amount of combustion is controlled by a controller 2. Reference numeral 5 denotes a heat transfer pipe for hot water supply, which is provided with a flow rate detecting device 3, an incoming water temperature detecting device 4 on an upstream side thereof and an outgoing hot water temperature detecting device 6 on a downstream side thereof, and these constitute a hot water supply circuit. 14 is a hot water tap. Reference numeral 9 denotes a bath heat transfer tube, which is connected to a bath water temperature detecting device 7, a flow switch 15, a circulation pump 8, and a bathtub 11 via a circulation tube 10 to form a bath circulation circuit.
The heat transfer tube 5 for hot water supply and the heat transfer tube 9 for bath are connected by heat absorbing fins 12 and are integrated into a one-can-two-water heat exchanger 13.
Is composed.

The operation of the above configuration will be described.
This water heater has two functions of a hot water supply operation for supplying hot water from a hot water tap 14 and a bath heating operation for circulating and heating water in the bathtub 11.

First, the hot water supply operation will be described. When the hot water tap 14 is opened, water flows in the hot water supply circuit due to tap water pressure.
The flow rate F1 is detected by the flow rate detection device 3 and the incoming water temperature Twi is detected by the incoming water temperature detection device 4, and the required combustion amount FF1 is calculated by the controller 2 based on these values and the hot water supply temperature set value Ts by the following formula. calculate.

FF1 = K (Ts−Twi) F1 K: Coefficient The heating burner 1 starts combustion at the value of the required combustion amount FF1 obtained by the above equation. As a result, hot water having substantially the same hot water temperature as the hot water temperature set value can be supplied from the hot water tap 14, but a normal error occurs. Correct the temperature deviation. When the hot water tap 14 is closed, the heating burner stops burning.

Next, the bath heating operation will be described. By operating the circulation pump 8, the water in the bathtub 11 flows through the bath circulation circuit. The flow switch 15 detects that there is running water,
When the bath temperature detecting device 7 detects that the temperature is lower than the bath temperature set value, the controller 2 controls the heating burner to start the combustion at the preset combustion amount FF2, and the bathtub 1
Heat the water in 1. When the bath temperature set value is reached, the heating burner stops burning.

When the hot water supply operation and the bath heating operation are simultaneously performed, the above operations are performed in a combined manner, and the combustion amount FF
3 is calculated by the following equation.

FF3 = FF1 + FF2 That is, at the moment when the simultaneous operation is started, the combustion amount of the heating burner is changed to a value FF3 obtained by adding the combustion amount of the value FF2 set in advance in the bath heating operation to the value FF1 required for the hot water supply operation. For example, when the hot water supply operation is performed with a combustion amount of 15,000 kca
When the bath heating operation is turned on while the operation is performed at 1 / h, the combustion amount changes to 25,000 kcal / h at that moment, and thereafter, the combustion amount is corrected to match the hot water supply temperature set value. When the bath heating operation is turned off, the combustion amount is 1500
After returning to 0 kcal / h, the combustion amount is corrected so as to match the hot water supply temperature set value. Further, if the calculated amount of combustion at the time of simultaneous operation of hot water supply and bath heating is 25000 kcal / h or more, the bath heating operation is not started.

According to the structure of this embodiment, as shown in FIG. 3, in the case of simultaneous operation of hot water supply and bath heating, bath heating is indispensable.
Combustion starts at the value FF3 that is the sum of the required amount of combustion FF2
To be temporarily reduced in hot water hot water temperature at the start of operation
In the case where only the bath heating operation is stopped from the simultaneous operation, the amount of combustion of the value FF2 necessary for bath heating is reduced instantaneously.
Since the combustion is started at the calculated value FF1, it is possible to provide a hot water supply apparatus which has a small variation in the hot water temperature and prevents a temporary rise in the hot water temperature and has a high usability. Further, when the temperature exceeds the combustible upper limit, the bath heating operation is not started, and it is possible to prevent water from being supplied only with hot water whose hot water temperature is lower than the set temperature.

[0018]

As described above, the water heater of the present invention has a heating burner whose combustion amount can be varied, a flow rate detection device, an input water temperature detection device, a heat transfer tube for transferring the heat of combustion of the heating burner, and a hot water outlet. A hot water supply circuit including a temperature detection device, a bath circulation circuit including a bath water temperature detection device, a flow switch, a circulation pump, and a heat transfer pipe for bath for transferring combustion heat of the heating burner; The heat tube and the heat transfer tube for the bath share a heat absorbing fin to constitute a heat exchanger.

The amount of combustion of the heating burner is a value obtained by adding a constant value to the value calculated by the flow rate detecting device and the incoming water temperature detecting device during the simultaneous operation of hot water supply and bath heating ;
In addition, since the amount of combustion is switched instantaneously, the temperature of the hot water supply temporarily decreases at the start of operation, and conversely, the temperature of the hot water supply increases temporarily when only the bath heating operation is stopped from the simultaneous operation state. Such fluctuations in hot water temperature can be prevented. In addition, a control device is provided to stop the bath heating operation when the value of the combustion amount plus a certain value exceeds the combustible upper limit, so that the hot water supply operation and the bath heating operation can be performed with the hot water temperature lower than the set temperature. Simultaneous operation can be prevented. Thus, a water heater with a high feeling of use can be provided.

[Brief description of the drawings]

FIG. 1 is a system diagram of a water heater according to an embodiment of the present invention.

FIG. 2 is a system diagram of a conventional water heater.

FIG. 3 is a hot water supply characteristic diagram in one embodiment of the present invention.

FIG. 4 is a diagram showing a hot water supply characteristic of a conventional water heater.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Heating burner 2 Controller 3 Flow rate detecting device 4 Incoming water temperature detecting device 5 Heat transfer tube for hot water supply 6 Outgoing water temperature detecting device 7 Bath temperature detecting device 8 Circulation pump 9 Heat transfer tube for bath 12 Heat absorbing fin 13 Heat exchanger

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁶ , DB name) F24H 1/00 604

Claims (1)

(57) [Claims] 1. A hot water supply circuit comprising a heating burner capable of varying the amount of combustion, a flow rate detection device, an input water temperature detection device, a hot water supply heat transfer tube for transmitting the combustion heat of the heating burner, and an output temperature detection device. A bath circulation circuit composed of a bath water temperature detector, a flow switch, a circulation pump, and a heat transfer tube for a bath, and a heat exchanger configured to share the heat transfer fin with the heat transfer tube for the hot water supply and the heat transfer tube for the bath , Control device to control burner combustion
The controller starts the combustion at a value calculated by the flow rate detection device and the incoming water temperature detection device during the hot water supply alone operation, and performs the hot water supply alone operation during the simultaneous operation of the hot water supply and the bath heating.
Regardless of the combustion amount variable range at the time
The bath heating operation is set to the value of the hot water supply alone operation with the limit value as the maximum
To a value obtained by adding a required constant value to at least the hot water supply unit.
Start combustion at a value greater than that of German operation
To simultaneous operation, or change from simultaneous operation to isolated operation.
Change the amount of combustion when it is done
A water heater in which the bath heating operation is stopped when the combustion amount of the burner exceeds a combustible upper limit value.