JP3489182B2 - 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 water heater having improved hot water outlet temperature characteristics when it is restarted after being stopped.

[0002]

2. Description of the Related Art In recent years, there has been a demand from the market for a water heater with improved temperature characteristics of hot water supplied when it is restarted after being stopped.

A conventional water heater will be described below. Conventionally, this type of water heater has a structure as shown in FIG. That is, the water passes from the water inlet through the water inlet temperature detecting device 1 and the hot water supply water amount detecting device 2, absorbs heat in the hot water supply heat exchanger 4 heated by the hot water supply burner 3, becomes hot water, and is discharged from the faucet 6. Next, when the faucet 6 is closed and the water amount signal from the hot water supply water amount detecting device 2 disappears, the combustion of the hot water supply burner 3 is stopped. When the combustion of this hot water supply is stopped, the hot water supply heat exchanger 4
The temperature of the hot water remaining in the passage of (1) rises due to the residual heat of the hot water supply heat exchanger 4 (so-called post-boiling), and a relatively short time
For example, in order to prevent the hot water from coming out when the machine is restarted after 1 minute, the hot water blower 9 is used even after the operation of the conventional hot water supply is stopped.
Was operated at a constant rotation speed for a predetermined time (usually 5 minutes) to cool the hot water remaining in the passage of the hot water supply heat exchanger 4.

[0004]

However, in the above-mentioned conventional configuration, whether the bath burner 15 forming the bath circuit provided inside the equipment of the water heater is in the burning state or the non-burning state, the hot water burner 3 is After the operation was stopped, the hot water supply fan 9 was operating at a constant rotation speed. That is, in a hot water supply device installed in an apartment such as a condominium in recent years, in which the hot water supply exhaust pipe portion 16a and the bath exhaust pipe portion 4a communicate with each other to form one exhaust passage, the bath burner 15 is in a burning state. If the temperature of the hot water supply exhaust pipe portion 16a and the hot water supply heat exchanger 4 rises due to the radiant heat from the exhaust gas passing through the bath exhaust pipe portion 4a, the hot water supply blower 9
Runs at a constant rotation speed and blows air to the hot water supply heat exchanger 4, so that the hot water remaining in the passage of the hot water supply heat exchanger 4 is difficult to cool. Therefore, when the hot water supply burner 3 is restarted for a relatively short time after the operation is stopped, for example, 1 minute later, the post-boiling W becomes large as shown by 1 in FIG.

In order to prevent boiling after this, the hot-water supply blower 9 is used even though the bath burner 15 is in a non-combustion state.
On the contrary, when the number of rotations of the hot water is increased, the hot water remaining in the passage of the hot water heat exchanger 4 is cooled too much, and when restarted after a relatively long time, for example, 5 minutes, as shown in 3 of FIG. In addition, there is a problem that the so-called precooling D becomes large and cold water comes out.

The present invention solves the above-mentioned problems of the prior art by reducing post-boiling without increasing precooling during restart of hot water supply, thereby providing excellent hot water temperature characteristics during intermittent use of hot water supply. The purpose is to provide a user-friendly water heater.

[0007]

In order to achieve the above object, the first means of the water heater of the present invention is a bath exhaust which communicates with the hot water supply exhaust cylinder and radiates radiant heat to the hot water supply exhaust cylinder. To the cylinder part, the hot water supply operation detector and the bath operation detector that detect the heating operation state by the burner of the hot water supply heat exchanger and the bath heat exchanger, respectively, and the combustion air to the burner and the both heat exchangers. When the hot-water blower and bath blower that supply cooling air for the cooling speed control and the hot-water supply operation detector detect heating stop, the rotation speed of the hot-water blower is controlled according to the detection signal of the bath operation detector, It is provided with a control means for rotating for a required time.

The second means of the water heater of the present invention is a timer for measuring a predetermined combustion time B from when the bath operation detector detects the heating operation of the burner, and this timer measures the predetermined combustion time B. It is provided with a control means for controlling the number of revolutions of the hot water blower according to a signal indicating whether or not it is.

Further, the third means of the water heater of the present invention measures the predetermined combustion time B from the start of the heating operation of the burner by the signal from the bath operation detector, and the heating operation of the burner is stopped after an arbitrary time has elapsed. A timer for measuring a predetermined stop time C from this stop and a control means for controlling the number of rotations of the hot water supply fan according to the presence or absence of a measurement signal of the predetermined stop time C from the timer are provided.

[0010]

According to the first aspect of the present invention, when the hot water supply burner is in a combustion state and the temperature of the hot water supply exchanger is high due to exhaust heat of the hot air burner when combustion of the hot water supply burner is stopped, the present invention operates for a required time. Since the number of rotations of the hot water supply fan is increased, the hot water remaining in the passages of the hot water heat exchanger can be quickly cooled, and the post-boiling can be reduced without increasing the pre-cooling when the hot water supply is restarted. .

Further, by the above-mentioned second means, the bath burner is in a combustion state when the combustion of the hot water supply burner is stopped, and this combustion state continues for a predetermined combustion time B or longer, so that the temperature of the hot water supply heat exchanger becomes sufficiently high. When the temperature is high, the number of revolutions of the hot-water supply fan that operates only for the required time is further increased, so that the hot water remaining in the passages of the hot-water supply heat exchanger can be quickly cooled, and the pre-cooling when the hot-water supply is restarted should be increased. In addition, after-boiling can be reduced.

Further, although the bath burner is in the non-combustion state by the above-mentioned third means, after the combustion state of the bath burner before the non-combustion state continues for a predetermined combustion time B or more, the bath burner is not burned. When the temperature of the heat exchanger for hot water supply has not dropped yet because the combustion state has not passed for the predetermined stop time C or more, the rotational speed of the hot water blower that operates for the required time is slightly increased, so the passage of the heat exchanger for hot water supply is increased. The hot water remaining inside can be cooled quickly, and the post-boiling can be reduced without increasing the pre-cooling when the hot water supply is restarted.

[0013]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a structure common to the first, second and third embodiments, and is different from FIG. 6 only in that a rotation speed switching control means 21 and a timer 24 of the hot water blower 9 are provided. . First, the hot water supply circuit will be described. From the water inlet, water enters the water temperature detecting device 1 and the hot water supply water amount detecting device 2.
Through the hot water supply burner 3 to absorb the heat into hot water, which passes through the hot water supply outlet temperature detecting device 5 and is discharged from the faucet 6. From the gas inlet, the gas passes through the hot water supply solenoid valve 7 and the hot water supply gas proportional valve 8, and is burned by the hot water supply blower 9 in the hot water supply burner 3. The exhaust gas generated at this time is discharged to the outside of the appliance through the hot water supply heat exchanger 4 and the hot water supply exhaust tube portion 4a. Reference numeral 9a is a hot water supply operation detector that detects this combustion state. The operation start of the water heater is input by the operation switch 11 of the external input device 10, and the set temperature is input by the hot water temperature switches 11a and 11b of the external input device 10. When a water amount signal is input from the hot water supply water amount detection device 2, the water heater starts combustion, and signals from the incoming water temperature detection device 1, the hot water supply water amount detection device 2, the hot water supply hot water discharge temperature detection device 5, and the external input device 10 are used. ,
The source solenoid valve 7 for supplying hot gas, the proportional gas valve 8 for hot water supply, and the blower 9 for hot water supply combustion are controlled and operated by the controller 23 so that the set hot water temperature is reached.

Explaining the bath circuit, the water in the bath (not shown) is sucked by the pump 13, passes through the circulation temperature detector 14, and is absorbed by the bath heat exchanger 16 heated by the bath burner 15. It becomes hot water, and this hot water is discharged into the bathtub. From the gas inlet, the gas passes through the bath solenoid valve 17, the bath gas proportional valve 18, and the bath blower 19.
Is burned in the bath burner 15. The exhaust gas generated at this time is generated by the heat exchanger 15 for the bath and the exhaust pipe portion 1 for the bath.
After passing through 5a, it merges with the hot water supply exhaust tube 4a and is discharged to the outside of the appliance. A bath operation detector 22 detects this combustion state. The external input device 10 starts the operation of the bath.
The bath combustion continues until the temperature of the hot water in the bathtub reaches the set temperature or the operation switch 20 is pressed again to stop the operation, and is burned independently of the hot water supply circuit.

In the water heater as described above, FIG. 2 shows the control sequence of the first embodiment of the present invention. S1
The operation switch 11 of the external input device 10 is turned on, and the set temperature is input by the hot water supply temperature switches 11a and 11b. When the faucet 6 is opened in S2 and water flows into the water passage and the water amount detected by the hot water supply water amount detection device 2 becomes equal to or larger than the ignition water amount, the ignition sequence is started in S3. In S4, the combustion amount of the hot water supply burner 3 is determined by the input signals of the external input device 10, the incoming water temperature detection device 1, and the hot water supply water amount detection device 2, and S5, S
At 6, the combustion amount of the hot water supply burner 3 is adjusted so that the input signal of the hot water supply hot water temperature detection device 5 and the input signal of the external input device 10 become the same.

When the faucet 6 is closed in S7 and the amount of water detected by the hot water supply water amount detecting device 2 becomes equal to or less than the amount of water for extinguishing water, the combustion of the hot water supply burner 3 is stopped in S8. In S9, the combustion state of the bath burner 15 at this time is detected by the bath operation detector 22,
When the bath burner 15 is not burning, the hot water supply blower 9 operates at the rotation speed N1 within the required time A in S10. Also,
When the bath burner 15 is burning in S9, the hot water supply blower 9 operates in the required time A at the rotation speed N2 in S11. Here, the rotation speed N1 <the rotation speed N2.

Next, when the water amount detected by the hot water supply water amount detecting device 2 becomes equal to or larger than the ignition water amount within the required time A after the combustion stop of the hot water supply burner 3 in S12, the process returns to S3. When the required time A has elapsed since the combustion of the hot water supply burner 3 was stopped in S13, S14
Then, the hot water supply blower 9 is stopped and the process returns to S2.

FIG. 3 shows the control sequence of the second embodiment of the present invention. Steps S1 to S10 in FIG. 3 are the same as those in FIG. When the combustion state of the bath burner 15 has not continued for the predetermined combustion time B or more in S11, the hot water supply fan 9 operates in the required time A at the rotation speed N3 in S12. Also, S
When the combustion state of the bath burner 15 continues for a predetermined combustion time B or more at 11, the hot water supply blower 9 rotates at the rotation speed N at S13.
4 will operate within the required time A. Here, the rotation speed N3 <the rotation speed N4.

Next, when the amount of water detected by the hot water supply water amount detecting device 2 becomes equal to or greater than the ignition water amount within the required time A after the combustion of the hot water supply burner 3 is stopped in S14, the process returns to S3. When the required time A has elapsed since the combustion of the hot water supply burner 3 was stopped in S15, S16
Then, the hot water supply blower 9 is stopped and the process returns to S2.

FIG. 4 shows the control sequence of the third embodiment of the present invention. The steps S1 to S9 in FIG. 4 are the same as those in FIG. When the bath burner 15 is burning in S9, the hot water supply blower 9 operates in the required time A at the rotation speed N2 in S11. Further, the bath burner 15 is in the non-combustion state in S9, and the bath burner 1 before it is in the non-combustion state in S10.
After the combustion state of No. 5 continues for a predetermined combustion time B or more, S12
When the non-combustion state of the bath burner 15 has passed the predetermined stop time C or more, the hot water supply blower 9 rotates the rotation speed N5 in S13.
It operates within the required time A. Also, in S12, the bath burner 1
When the non-combustion state of No. 5 has not elapsed for the predetermined stop time C or more, the hot water supply blower 9 is at the rotation speed N6 at the required time A at S14.
It works within. Here, the rotation speed N5 <the rotation speed N6.

Next, when the water amount detected by the hot water supply water amount detecting device 2 becomes equal to or larger than the ignition water amount within the required time A after the combustion stop of the hot water supply burner 3 in S15, the process returns to S3. When the required time A has elapsed since the combustion of the hot water supply burner 3 was stopped in S16, S17
Then, the hot water supply blower 9 is stopped and the process returns to S2.

As described above, when the hot water supply is stopped, the number of revolutions of the hot water supply blower 9 within the required time A is switched according to the combustion state and the non-combustion state of the bath burner 15. Therefore, when the hot water supply is restarted, as shown in FIG. After-boiling W shown in 1 and 3 in FIG.
The pre-cooling D shown in Fig. 5 is small, and there is little after-boiling and pre-cooling at the time of re-operation as shown in 2 and 4 in Fig. 5, and a convenient water heater with excellent hot-water supply characteristics during intermittent use such as a shower. Become.

[0024]

As is clear from the above description, the water heater of the present invention has the following effects. In claim 1, when the hot water supply burner stops heating, the radiant heat of the exhaust gas of the bath burner to the hot water supply heat exchanger is generated when the bath heat exchanger is in a heating operation state by the bath burner according to a signal from the bath operation detector. When there is a large amount of heat, the radiant heat is added to the heat storage of the hot water supply heat exchanger itself, and the amount of post-boil of the stored water in the hot water supply heat exchanger increases, so that the number of rotations of the hot water supply fan increases to supply hot water by exhausting the bath burner. The effect on post-boiling of the heat exchanger can be adjusted.

According to claim 2 of the water heater of the present invention, the timer measures the predetermined combustion time B from the time when the hot water supply burner stops heating and the time when the bath operation detector detects the heating operation of the bath burner. When there is a large amount of radiant heat from the exhaust gas of the bath burner to the heat exchanger for hot water supply when the heat exchanger is in the heating operation state with the bath burner, the heat received by the radiant heat is added to the heat stored in the heat exchanger for hot water supply to heat the hot water supply. By increasing the number of revolutions of the hot water supply blower by the amount of the post-boiling of the water stored in the exchanger, it is possible to adjust the influence of the exhaust gas of the bath burner on the post-boiling of the hot water supply heat exchanger.

Further, in claim 3 of the water heater of the present invention, when the heating of the hot water supply burner is stopped, a predetermined combustion time B from the start of the heating operation of the bath burner is given by a signal from the bath operation detector.
After the timer measures, the heating operation of the bath burner is stopped, the predetermined stop time C from this stop does not elapse, and the bath heat exchanger is in a heating state by the bath burner When there is a large amount of radiant heat from the burner exhaust, the number of revolutions of the hot-water supply fan should be increased by the amount that the post-boiling of the stored water in the hot-water supply heat exchanger increases due to the addition of the received radiant heat to the heat storage of the hot-water supply heat exchanger itself. This makes it possible to adjust the influence of the exhaust gas from the bath burner on the post boiling of the heat exchanger for hot water supply.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a water heater according to first, second and third embodiments of the present invention.

FIG. 2 is a flowchart of a water heater control sequence according to the first embodiment of the present invention.

FIG. 3 is a flowchart of a water heater control sequence in the second embodiment of the present invention.

FIG. 4 is a flowchart of a water heater control sequence according to a third embodiment of the present invention.

[Figure 5] Hot water supply characteristic diagram

FIG. 6 is a configuration diagram of a conventional water heater.

[Explanation of symbols]

3 hot water supply burner 4 Hot water heat exchanger 4a Exhaust pipe for hot water supply 9 Hot water blower 9a Hot water supply operation detector 15 bath burner 16 Bath heat exchanger 16a Exhaust tube for bath 19 bath blower 21 Rotation speed switching control means 22 Bath operation detector 24 timer

─────────────────────────────────────────────────── ─── Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) F23N 3/08 F24H 1/00

Claims (3)

(57) [Claims] 1. A bath exhaust tube portion communicating with the hot water supply exhaust tube portion and radiating heat to the hot water supply exhaust tube portion, and a heating operation state by a burner of the hot water supply heat exchanger and the bath heat exchanger, respectively. Hot water supply operation detector and bath operation detector to detect, hot water supply blower and bath air blower for supplying combustion air to the burner and cooling air to both heat exchangers, respectively, and the hot water supply operation detector stops heating When detecting, the water heater having a control means for controlling the number of rotations of the hot water blower according to the detection signal of the bath operation detector and rotating the hot water blower for a required time. 2. A timer for measuring a predetermined combustion time B from the time when the bath operation detector detects the heating operation of the burner, and a timer for the hot-water supply fan according to a signal indicating whether or not the timer has measured the predetermined combustion time B. The water heater according to claim 1, further comprising control means for controlling the number of revolutions. 3. A predetermined combustion time B is measured from the start of the heating operation of the burner by a signal from a bath operation detector, the heating operation of the burner is stopped after an arbitrary time has elapsed, and a predetermined stop time C from this stop is measured. The water heater according to claim 1, further comprising: a timer for controlling the number of revolutions of the hot water heater and a control means for controlling the number of rotations of the hot water blower according to the presence or absence of a measurement signal of the predetermined stop time C from the timer.