JP2002013803A - Bath furnace equipped hot water supply appliance - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce any combustion sound upon additional burning for heat insulation and improve performance of keeping unchanged temperature of water in a bathtub. SOLUTION: A seed heater is provided as an auxiliary heat source on a circulation circuit that connects a bath and a hot water supply appliance, and upon additional burning for heat insulation heating is achieved with this auxiliary heat source. Heating with the seed heater is milder than that where gas and petroleum oil are employed as a fuel to shorten heat insulation time interval. Hereby, the degree of lowering of water temperature in the bath during the heat insulation time interval can be reduced to improve heat insulation performance.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water heater with a bath kettle, which has reduced combustion noise during a warming operation and has improved warming performance.

[0002]

2. Description of the Related Art In a conventional water heater with a bath, a warming operation for keeping a constant temperature even after the hot water is known. This is to periodically operate the circulation pump provided in the circulation circuit that connects the bath and the water heater, and if the water temperature of the bath at that time is lower than the bath set temperature, perform additional heating,
The one that always keeps the bath set temperature,
As shown in JP-A-111013, there is a type in which a combustor for additional heating is eliminated and the temperature is kept by an electric heater. Here, the prior art will be described with reference to FIGS.

FIG. 4 is a block diagram of a conventional gas water heater with a bath kettle. As shown in the drawing, hot water is supplied through a hot water supply body 1, a water supply pipe 3 for supplying water from the water supply source to the hot water supply body 1, and water heated in the hot water supply body 1 via a hot water supply heat exchanger 7. The hot water supply pipe 5 for supplying to the stopper 11 is constituted. Further, a bypass pipe 43 branched from the water supply pipe 3 in the water heater main body 1 and connected to the hot water supply pipe 5 without passing through the hot water supply heat exchanger 7, and a junction of the bypass pipe 43 and the hot water supply pipe 5 include: A mixing valve 41 is provided for mixing and controlling the hot water heated by the hot water supply heat exchanger 7 and the water sent from the bypass pipe 43 by a stepping motor M driven based on a command pulse. The water supply pipe 3 has a temperature T from the hot water supply source.
c, a water supply water sensor 27 for detecting the amount of water Q, and a heat for detecting the temperature Th at the outlet of the hot water supply heat exchanger 7 upstream of the mixing valve 41 of the hot water supply pipe 5. On the downstream side of the exchanger outlet temperature sensor 45 and the mixing valve 41, a mixed hot water temperature detection sensor 29 for detecting the mixed hot water temperature Tm after mixing is provided.

[0004] Further, a fan 9 for supplying air required for combustion is provided in the water heater main body 1. In addition, an igniter 1 necessary for igniting is provided above the burner 13.
5. A frame rod 17 for detecting the presence or absence of a flame is provided. A gas supply pipe 23 for supplying gas to the burner 13 is provided. The gas supply pipe 23 has a proportional valve 19 for varying the amount of gas to be supplied and an electromagnetic valve for starting / stopping gas supply. 21 are provided.

[0005] Further, the gas water heater is connected to the additional heating return pipe 2 from the hot water supply pipe 5 in the water heater main body 1 downstream of the mixing valve 41.
The filling pipe 4 is provided with a filling water quantity sensor 8 for detecting a flow rate flowing through the filling pipe 4 and a hot water solenoid valve 6 for starting / stopping the supply of hot water. Have been. On the other hand, the additional heating return pipe 2 and the additional heating forward pipe 53 constituting the bathtub water circulation circuit are attached at their ends to the bathtub 12, and a pump P for circulating hot water in the bathtub 12 and a circulation flow A bath temperature sensor 49 for detecting the temperature of hot water in the bathtub 12 by detecting the temperature of the bath and a bath water flow switch 50 for detecting the presence or absence of water in the bathtub 12 are provided.

The remote controller 33 has an operation switch 3
5. A temperature setting switch 39 for setting a set temperature Ts of the hot water supplied from the hot water tap 11 and a bath set temperature Tfs of the hot water when the hot water is filled in the bathtub 12 or during the reheating operation, and after the hot water is poured into the bathtub. Also, a hot water insulation switch 36 that is turned on when performing the heat retention operation for a predetermined time, and a supplementary heat insulation switch that is turned on when the heat retention operation is performed for a predetermined time after reheating the hot water in the bathtub 12 and after the reheating. 38, set temperature Ts, bath set temperature Tf
The display unit 37 for displaying s and the like is provided. The gas water heater further includes detection signals (Tc, Q, Th, T, Tc) from the sensors 25, 27, 45, 29 and the temperature setting switch 39.
m, Ts, Tfs), the proportional valve 19, the solenoid valve 2
1, a control unit 31 for controlling the fan 9, the mixing valve 41 and the like
Is also provided. The control unit 31 and each sensor and the proportional valve 1
9, the electromagnetic valve 21, the fan 9, the mixing valve 41, and the like can transmit and receive signals by wire or wireless (not shown).

Next, a description will be given of the operation of reheating the hot water in the bathtub 12 and performing the heat retaining operation for a predetermined time after the reheating.
When the reheating switch 38 is pressed while the operation switch 35 of the remote controller 33 is turned on, the pump P provided in the circulation circuit including the reheating return pipe 2 and the reheating pipe 53 starts operating, The hot water in the bathtub 12 is circulated. At this time, the presence or absence of water in the bathtub 12 is detected by the bath water flow switch 50, and the temperature T of the water in the bathtub 12 is detected by the bath temperature sensor 49.
Detect f. The bath setting temperature Tfs set in advance by the temperature setting switch 39 of the remote controller 33 is compared with the bath temperature Tf detected by the bath temperature sensor 49 during the circulation of the pump. (Tfs−2 ° C.)> When Tf, the heat retention and additional heating heat exchanger 14 is burned to start additional heating. After that, when Tfs ≦ Tf, the combustion is stopped and the operation is continuously shifted to the heat keeping operation.

FIG. 5 is a time chart showing the operation of the warming operation in the block diagram of FIG. After the predetermined heat retention interval time T _INT has elapsed, the pump P
And the bath temperature Tf at that time and the bath set temperature Tfs
If the relationship of (Tfs-2 ° C)> Tf is established, the process proceeds to reheating heating (A in the figure). If (Tfs-2 ° C) ≦ Tf, the process proceeds to the heat retention interval again without reheating. (A in the figure). Thereafter, the above operation can be repeated to keep the temperature of hot water in bathtub 12 constant.

[0009]

However, in the conventional heat-retaining operation, there is a problem that noise is generated during combustion because gas or oil is used as a heat-retaining heat source. However, the temperature difference between the bath set temperature Tfs and the bath temperature Tf, which is a criterion for determining whether or not to reheat during the circulation of the pump, must be set to a relatively large value (2 ° C. in the above example). Did not get.
This indicates that the fluctuation range of the bath temperature during the heat retention operation has a relatively large value. On the other hand, if the reheating is not performed for a long time, the temperature fluctuation such as an increase in the degree of decrease in the temperature of the bath water increases, causing a problem that the user feels uncomfortable especially in winter. Therefore, the current products generally provide a heat retention interval of about 8 minutes due to both trade-offs, but in densely populated houses in cities, etc., the frequency of noise gas combustion noise and bath temperature fluctuations are still sufficiently satisfactory. Not at the level to go. In addition, there is a limitation in the capacity of the heater for heating only with an electric heater without a combustor for reheating, and there is a problem in rapid heating capacity.

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 reduce the reburning combustion noise during the warming operation and not to be concerned about a decrease in bath water temperature during the warming interval. An object of the present invention is to provide a water heater with a bath kettle having improved heat retention performance.

[0011]

In order to achieve the above object, a first aspect of the present invention is to heat water passed through a heat exchanger for additional heating and a heat exchanger for supplying hot water by combustion heat of a combustor. In the one-can-two-channel water heater with a bath kettle, the auxiliary heat exchanger having an electric heating means between the circulation circuit connecting the bath and the water heater has the auxiliary heat exchanger during the bath heating and reheating operation. It is possible to eliminate the reheating combustion sound during the reheating and reheating operation by performing the heating and the heat retention operation.

In the second invention, a control circuit can be easily realized by using a sheathed heater as the electric heating means of the auxiliary heat exchanger.

A third aspect of the present invention has a bath water temperature detecting means for detecting a bath water temperature and a bath temperature setting means for setting a bath water temperature, and the bath water temperature and the bath set temperature during a bath warm-up reheating operation. When the difference is less than the predetermined temperature range, the auxiliary heat exchanger heats the bath water to reduce the reburning combustion noise during the warm-up operation and controls the electric heating means for more precise temperature control. Becomes possible.

According to a fourth aspect of the present invention, there is provided a bath water temperature detecting means for detecting a bath water temperature, and a bath temperature setting means for setting a bath water temperature. When the difference is equal to or more than a predetermined temperature range, the time required for reheating can be shortened by heating the bath water with the heat retention reheating exchanger and the auxiliary heat exchanger.

According to a fifth aspect of the present invention, there is provided a bath water bypass which directly connects an inlet and an outlet of the circulation circuit to the heat exchanger for additional heat retention, and an opening / closing means for opening and closing the bath water bypass. During the reheating operation, the bath water bypass path is connected and circulated, shortening the circulation circuit and eliminating the heat exchanger for heating and reheating that is heated by the combustor. Temperature drop can be prevented.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION In order to make the contents of the present invention easier to understand, the present invention will be described below with reference to examples.

[0017]

FIG. 1 is a block diagram of a water heater with a bath kettle showing an embodiment of the present invention. In the figure, components having the same reference numerals and numbers as those in FIG. 4 have the same structure or the same functions as those of the conventional example shown in FIG. Reheating pipe 2
An auxiliary heat exchanger 60 is newly provided in the middle of the circulation circuit including the additional heating pipe 53 and the auxiliary heating pipe 53. The auxiliary heat exchanger 60 uses a sheathed heater as a heat source. The heating by the sheathed heater does not care about the noise at the time of heating as compared with the heating by burning gas or oil, so that reheating can be frequently performed.

FIG. 2 is a time chart showing the operation of the warming operation in the block diagram of FIG. The temperature difference (Tfs) between the bath set temperature Tfs and the bath temperature Tf, which is to determine whether the heat retention interval time T _INT is as short as about half the conventional value and whether additional heating is performed during circulation of the pump.
−Tfs ′) is also halved from the conventional case. Since the combustion noise is eliminated by heating in the auxiliary heat exchanger, there is no problem of noise even if the number of times of reheating per unit time is larger than in the past. In addition, since the temperature control width during the warming operation can be reduced, the fluctuation width of the bath temperature is reduced, and stable and more comfortable bathing can be performed.

By the way, in the case of bath water heating after leaving the apparatus without keeping it warm for a while, that is, when the temperature difference between the bath set temperature Tfs and the actual bath temperature Tf is large,
It is conceivable that the heating power of the auxiliary heat exchanger increases the time required for heating. In such a case, instead of heating with the auxiliary heat exchanger, heating with a heat-retaining additional heat exchanger using gas or oil as fuel is selected to shorten the additional heating time. The determination of which heating means to select is made by selecting the auxiliary heat exchanger when the temperature difference between the bath set temperature Tfs and the actual bath temperature Tf is Ths>Tf> (Tfs-1 ° C.), and (Tfs-1 ° C) ≧ Tf, the heat exchanger for additional heat retention is selected.

Further, when the heating by the auxiliary heat exchanger and the combustion on the hot water supply side are simultaneously performed in the one-tank two-water channel water heater, the solenoid valve 62 for opening and closing the bypass path is closed, and By allowing the hot water to pass through the heat-retention and reheating heat exchanger 14, both the auxiliary heat exchanger and the heat-retention and reheating heat exchanger can be heated, and the time required for reheating is reduced. There is an advantage.

FIG. 3 shows a heat exchanger 1 for keeping the heat in the circulation circuit.
Bath water bypass 61 that bypasses the entrance and exit of 4
And a solenoid valve 62 for opening and closing the bypass passage 61. At the time of warming and heating by the auxiliary heat exchanger, the opening / closing solenoid valve 62 is opened so that hot water in the circulation circuit passes through the bypass path.
There is a feature that the heat radiation in No. 4 can be prevented.

[0022]

According to the present invention, the following effects are exhibited by the above configuration.

Since the sheathed heater is used as an auxiliary heat source at the time of additional heating in the heat retention operation, there is no combustion noise and the noise can be reduced.

There is no particular problem even if reheating is performed frequently due to silence, the interval time can be set shorter than before, and the temperature between the bath set temperature and the actual bath temperature, which is a judgment on whether to reheat, is made. Since the difference can be set to a small value, the degree of decrease in the bath water temperature during the interval time is reduced, and the heat retention performance can be improved.

Further, since the bath water bypass which directly connects the inlet and the outlet of the circulation circuit to the heat exchanger for additional heating and heating is provided, the heat radiation of the water temperature in the circulation circuit heated by the sheathed heater can be reduced. Energy saving can be achieved.

Heating by the sheathed heater is performed when the bath water temperature is relatively close to the bath set temperature, and when the difference between the bath water temperature and the bath set temperature is large, conventional reheating using gas or oil is used. The time required for reheating from a low temperature is not inferior to the conventional one.

Furthermore, in the case of a one-can, two-drain water heater,
The bath water bypass is closed when hot water is used during warm-up reheating by the sheathed heater, so it is necessary for reheating by adding heat from a heat-retaining reheating heat exchanger that uses gas or oil as fuel. You can save time.

Although the embodiments of the present invention have all been described with a one-can, two-channel water heater, it is needless to say that the same effects can be obtained in a two-can, two-channel water heater.

[0029]

[Brief description of the drawings]

FIG. 1 is a block diagram of a water heater with a bath kettle according to the present invention.

FIG. 2 is a time chart of an operation of keeping warm the heating of the auxiliary heat exchanger in the present invention.

FIG. 3 is a block diagram of a water heater with a bath kettle having a bypass water channel according to the present invention.

FIG. 4 is a block diagram of a conventional water heater with a bath kettle.

FIG. 5 is a time chart of a conventional heat retaining operation.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Hot water supply main body 2 ... Additional heating return pipe 3 ... Water supply pipe 4 ... Hot water supply pipe 5 ... Hot water supply pipe 6 ... Hot water solenoid valve 7 ... Hot water supply heat exchanger 8 ... Hot water supply water quantity sensor 9 ... Fan 11 ... Hot water tap 12 ... Bathtub 13 ... Burner 14 ... Heat exchanger for heat retention and additional heating 15 ... Igniter 17 ... Frame rod 19 ... Proportional valve 21 ... Solenoid valve 23 ... Gas supply pipe 25 ... Incoming water temperature sensor 27 ... Water supply water amount sensor 29 ... Mixed hot water temperature detection Sensor 31 ... Control unit 33 ... Remote control 35 ... Operation switch 36 ... Hot water insulation switch 37 ... Display unit 38 ... Additional heating insulation switch 39 ... Temperature setting switch 41 ... Mixing valve 43 ... Bypass tube 45 ... Hot water heat exchanger outlet temperature Sensor 47: Boiling temperature sensor 49: Bath temperature sensor 50: Bath water flow switch 53: Additional heating pipe 60: Auxiliary heat exchanger 61: Bath water bypass 62: Opening / closing solenoid valve P… Circulation pump M… Stepping motor

Continued on front page F term (reference) 3L024 CC07 CC11 DD04 DD13 DD17 DD22 DD23 DD27 DD28 EE02 FF11 GG03 GG04 GG06 GG22 GG24 GG27 GG38 HH13 HH22 HH24 HH26 HH36

Claims (5)

[Claims] Claims: 1. A one-can-two-channel water heater with a bath kettle for heating water passed through a heat exchanger for additional heating and a heat exchanger for hot water supply by the heat of combustion of a combustor, comprising: A water heater having an auxiliary heat exchanger having an electric heating means between circulation circuits connecting the heat exchangers, and performing a heat-retaining operation by heating with the auxiliary heat exchanger during a bath-heating and reheating operation. 2. The water heater according to claim 1, wherein a sheathed heater is used as electric heating means for said auxiliary heat exchanger. 3. The water heater according to claim 1, wherein
A bath water temperature detecting means for detecting a bath water temperature, and a bath temperature setting means for setting a bath water temperature, wherein a difference between the bath water temperature and the bath set temperature is less than a predetermined temperature range during a bath heat-up operation. A hot water heater characterized in that the bath water is heated by the auxiliary heat exchanger at the time. 4. The water heater according to claim 1, wherein
A bath water temperature detecting means for detecting a bath water temperature, and a bath temperature setting means for setting a bath water temperature, wherein a difference between the bath water temperature and the bath set temperature is greater than or equal to a predetermined temperature range during a bath heat-up operation. A hot water heater characterized in that the bath water is heated by the heat-retaining additional heat exchanger and the auxiliary heat exchanger at the time. 5. The water heater according to claim 1, wherein
A bath water bypass directly connecting the inlet and the outlet to the heat exchanger for heat retention and reheating of the circulation circuit, and an opening / closing means for opening and closing the bath water bypass are provided. A water heater characterized by communication and circulation.