JP3844604B2 - Combined water heater - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a composite water heater having a hopper in a branch pipe connecting a hot water supply pipe for pouring hot water and a reheating pipe for circulating and heating water or hot water in a bathtub. The present invention relates to a composite water heater to be performed.
[0002]
[Prior art]
Conventionally, this type of combined water heater is configured as shown in FIG. 5, for example.
In the figure, the composite water heater 1 includes a hot water supply heat exchanger 2 and a bath heat exchanger 3 in the main body.
The hot water supply pipe 4 for pouring is provided with a branch pipe 6 that branches from here and is connected to the follow-up pipe 5.
[0003]
The branch line 6 is provided with a hopper 7 that separates the hot water supply line 4 and the follow-up line 5 by air. The hopper 7 includes a pouring electromagnetic valve 8, a drainage tank 9 for collecting remaining water when separated, a drainage tank valve 10, a negative pressure closing valve 11, and a check valve 12.
The drainage tank 9 is connected to the follow-up pipeline 5 by a drainage pipeline 13, and a check valve 14 and a drainage electromagnetic valve 15 are provided in the drainage pipeline 13. Further, the drain tank 9 is provided with a drain port 16 that regulates the maximum amount of water and a water level switch 17 that opens and closes the drain electromagnetic valve 15.
[0004]
The follow-up pipeline 5 is connected to the circulation fitting 19 of the bathtub 18 to form a follow-up circulation pipeline. The circulation pipeline 5 includes a two-way valve 20, a circulation pump 21, and a follow-up thermistor 22. Has been placed.
A pressure sensor 23 that detects the water level of the bathtub 18 is disposed in the branch line 6 branched from the hot water supply line 4.
[0005]
In such a combined water heater 1, when filling the bathtub 18, as shown in FIG. 5, the hot water supply pipe 4 and the circulation pipe 5 are connected by a hopper 7 provided in the branch pipe 6. Hot water is supplied through the circulation line 5.
Specifically, when an automatic switch (not shown) is turned on, first, the pouring electromagnetic valve 8 is opened, and hot water is double-conveyed from the branch pipe 6 through the return pipe 5a and the forward pipe 5b of the circulation pipe 5.
When hot water is filled to a preset water level and the pressure sensor 23 detects that the water level in the bathtub 18 has reached the set water level, the pouring electromagnetic valve 8 is closed, the circulation pump 21 is turned on, and the two-way valve 20 is turned on. Confirm that this state continues for a certain period of time.
[0006]
Next, the temperature of the hot water drawn from the bathtub 18 is detected by the chasing thermistor 22. When the detection result is lower than the lower limit allowable temperature range of the set temperature set by a remote controller (not shown), the combustion by the reheating burner (not shown) is continued and the hot water in the bathtub 18 is maintained at a predetermined circulation flow rate. , Until the set temperature is reached.
[0007]
When the pouring electromagnetic valve 8 is closed, as shown in FIG. 6, the hopper 7 separates the hot water supply line 4 and the reheating line 5 from each other. At this time, the negative pressure closing valve 11 of the hopper 7 rises. ing.
And in the drain tank 9 of the hopper 7, the residual water at the time of air separation collects.
[0008]
When the remaining water in the drain tank 9 reaches a certain amount, as shown in FIG. 7, the water level switch 17 is turned on, the circulation pipe 5 is shut off by the two-way valve 20, and the drain electromagnetic valve 15 is opened. Circulation pump 21 discharges remaining water to bathtub 18.
[0009]
[Problems to be solved by the invention]
By the way, in the conventional combined water heater 1, the residual water when the hot water supply pipe 4 and the circulation pipe 5 are separated by air by the hopper 7 is opened, the drain pipe 13 is opened by the drain electromagnetic valve 15, Although it is discharged to the bathtub 18 through the circulation line 5, if the hopper 7 freezes in the winter, the inside of the drain tank 9 becomes full and water overflows to the separation air side, or automatic hot water filling operation, etc. There is a risk that it will not be possible.
[0010]
In this case, in the conventional anti-freezing operation, the two-way valve 20 of the circulation line 5 is not shut off, and the circulating pump 21 is turned on when the detected temperature of the reheating thermistor 22 becomes 2 degrees Celsius or less (ST1). (ST2), the hot water in the bathtub 18 is circulated to prevent the circulation line 5 from freezing. When the detected temperature of the reheating thermistor 22 becomes 4 degrees Celsius or higher (ST3), the circulation pump 21 is turned off (ST4).
[0011]
However, since the inside of the drainage tank 9 is isolated from the circulation pipe 5 by the separation air and the check valve 14, freezing of the remaining water in the drainage tank 9 cannot be prevented by this freeze prevention operation.
[0012]
The present invention has been made to solve the above-described problems, and can ensure that the drainage tank is prevented from freezing by reliably draining the remaining water accumulated in the drainage tank before the hopper drainage tank is frozen. The purpose is to provide a combined water heater.
[0013]
[Means for Solving the Problems]
According to the present invention, the above object is achieved by the present invention, wherein a hot water supply pipe for heating and pouring hot water and a reheating pipe for circulating and heating water or hot water in a bathtub are separated from each other by air, and the reheating pipe A thermistor provided in the drainage tank of the road and / or the hopper, and when the temperature detected by the thermistor provided in the drainage tank of the tracking pipe and / or the hopper is equal to or lower than a predetermined temperature. Check if there is residual water in the drain tank of the hopper and check that the drain tank is empty, or if there is residual water in the drain tank, drain the This is achieved by a combined water heater in which the water is emptied and the circulation pump is turned on to circulate the hot water in the bathtub to the follow-up pipeline.
[0015]
The circulating pump is turned on when the detected temperature of the thermistor is lower than a predetermined first temperature, and the circulating pump is turned off when the detected temperature is higher than a predetermined second temperature. Also good.
[0016]
According to the invention, when the temperature detected by the thermistor provided in the draining tank and / or the drain tank of the hopper becomes equal to or lower than a predetermined temperature, the circulation pump is turned on to bathe the hot water in the bathtub. The circulation line is prevented from freezing. That is, for example, when the temperature detected by the chasing thermistor is equal to or lower than a first temperature, the circulating pump is turned on, and when the temperature is equal to or higher than the second temperature, the circulating pump is turned off.
In this case, the thermistor may be provided in the circulation line, the drain tank, or both. The above operation is performed based on the detected temperature of any thermistor or the detected temperatures of all thermistors.
Furthermore, when the circulation pump is turned on, it is confirmed that the hopper drain tank is empty, so that the drain tank does not freeze.
[0017]
Also, when turning on the circulation pump, the presence or absence of residual water in the drain tank was checked, and if there was residual water in this drain tank, it was drained, so before the drain tank was frozen, Residual water accumulated in the interior can be surely drained.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described in detail with reference to the accompanying drawings.
The embodiments described below are preferred examples of the present invention, and thus various technically preferable limitations are given. However, the scope of the present invention is particularly limited in the following description. As long as there is no description of the effect, it is not restricted to these aspects.
[0019]
FIG. 3 is a system diagram showing a main configuration of the composite water heater employed in the present embodiment. In the figure, a combined water heater 31 includes a hot water supply heat exchanger 32 and a bath heat exchanger 33 in the main body, and is branched from a hot water supply line 34 and connected to a tracking pipe 35. A path 36 is provided.
[0020]
The hot water supply pipe 34 includes a water supply pipe 34 a to which water is supplied and a hot water supply pipe 34 b extending from the water supply pipe 34 a through the hot water supply heat exchanger 32. A water amount sensor 37 and a water thermistor 38a are connected to the water supply pipe 34a, and a hot water supply thermistor 38b and a water control unit 39 are connected to the hot water supply pipe 34b.
[0021]
The follow-up pipeline 35 is connected to the circulation fitting 40a of the bathtub 40 to form a follow-up circulation pipeline. The return pipe 35a has a two-way valve 41 for opening and closing the pipeline, and the return pipe 35a has hot water. Alternatively, a reheating water switch 42 for detecting that water has flowed, and a circulation pump 43 for drawing hot water in the bathtub 40 into the circulation pipe 35 are provided.
The return pipe 35 a of the circulation pipe 35 is provided with a chasing thermistor 44 on the entrance side of the bath heat exchanger 33. The forward pipe 35 b of the circulation pipe 35 extends from the bath heat exchanger 33 to the circulation fitting 41.
As shown in FIG. 3, the thermistor 44 a may be provided in the drainage tank 48 of the hopper instead of or in addition to the follow-up thermistor 44. In this case, the thermistor 44a may be located at any position where it contacts with the remaining water in the tank, and may preferably be attached by finding a location that is likely to freeze due to a decrease in temperature.
[0022]
A branch pipe 36 branched from the hot water supply pipe 34 b is provided with a hopper 45 that separates the hot water supply pipe 34 and the circulation pipe 35 from the air, and a pressure sensor 46 as a water level detection means of the bathtub 40.
The hopper 45 is provided with a pouring solenoid valve 47 for introducing hot water from the hot water supply pipe 34b, a drain tank 48 for storing residual water when air is separated, a drain tank valve 49, a negative pressure shut-off valve 50, and a check valve 51. ing.
[0023]
The drain tank 48 is connected to the circulation pipe 35 by a drain pipe 52, and a check valve 53 and a drain electromagnetic valve 54 are provided in the drain pipe 52. Further, the drainage tank 48 is provided with a drainage port 55 that regulates the maximum amount of water and a water level switch 56 that opens and closes the drainage electromagnetic valve 54.
[0024]
FIG. 4 shows a main device configuration for the control unit 60, and the method for preventing freezing of the composite water heater according to the present invention is realized by such a device configuration.
That is, in FIG. 4, a remote controller (not shown) is connected to the control unit 60, and the user can give a predetermined instruction such as setting a set temperature as a boiling temperature by the remote controller. The remote controller is equipped with a hot water pouring switch, a chasing switch, etc. (not shown).
[0025]
Further, the control unit 60 is connected to the water amount sensor 37, the incoming water thermistor 38a, the hot water supply thermistor 38b, the pressure sensor 46, the water level switch 56, the additional water flow switch 42, the additional water thermistor 44 and / or the thermistor 44a. Each detection signal is input.
Further, the control unit 60 adjusts the amount of fuel gas supplied to the circulation pump 43, the pouring electromagnetic valve 47, the two-way valve 41, the drain electromagnetic valve 54, and a hot water supply burner or a reheating burner (not shown). Proportional valves 62 and 63 are connected, and a control signal is output to each.
[0026]
Here, the storage unit 61 built in the control unit 60 stores PQ data and the like necessary for automatic operation of the composite water heater 31.
That is, the operation of the composite water heater 31 is performed by the control unit 60 based on the PQ characteristic based on the bathtub water level (P) and the amount of hot water (Q). This PQ characteristic is created by detecting the output voltage of the pressure sensor 46 based on the amount of poured water and the bathtub water level. Actually, when the pressure sensor 46 detects a pressure corresponding to the set water level, the hot water filling is automatically stopped.
Since this PQ characteristic is different depending on the shape of the bathtub to which the combined water heater is connected, it is created corresponding to each bathtub when installing the appliance, and the storage section of the combined water heater Is stored in advance.
[0027]
When the pouring electromagnetic valve 47 is closed by completing the automatic hot water filling based on such PQ data, the hopper 45 separates the hot water supply line 34 and the follow-up line 35 from the air. At this time, the negative pressure shut-off valve 50 of the hopper 45 is raised, and the residual water when air is separated accumulates in the drain tank 48 of the hopper 45.
When there is a certain amount of residual water in the drain tank 48, the water level switch 56 is turned on, the circulation pipe 35 is shut off by the two-way valve 41, the drain electromagnetic valve 54 is opened, and the circulation pump 43 removes the residual water. Drain to bathtub 40.
[0028]
In winter, in order to prevent the hopper 45 from freezing, the freeze prevention method of the present composite water heater is performed as follows.
That is, as shown in FIG. 1, first, the control unit 60 determines the detected temperature based on the input signal of the tracking thermistor 44 (ST11). When the detected temperature exceeds 2 degrees Celsius, the process does not proceed to the next step.
[0029]
When the temperature detected by the tracking thermistor 44 is 2 degrees Celsius or less, the presence or absence of residual water in the drain tank 48 of the hopper 45 is confirmed by checking whether or not the empty flag is turned on on the control software (ST12). In this case, when the drain electromagnetic valve 54 is already opened and the residual water is discharged to the bathtub 40 by the circulation pump 43, the empty flag is turned on on the control software. That is, if it is confirmed that the empty flag is on, the inside of the drainage tank 48 is empty.
In this case, if the thermistor 44a is provided in the drain tank 48, the detected temperature of the thermistor 44a may be confirmed instead of or in addition to the detected temperature of the follow-up thermistor 44. By doing so, it is possible to reliably prevent freezing in the drainage tank 48 even if there is a temperature difference between the tracking pipe line and the drainage tank 48.
[0030]
On the other hand, if it is not possible to confirm that the empty flag is turned on, a draining operation as shown in FIG. 2 is performed (ST21).
That is, in this drainage operation, first, the two-way valve 41 is switched to the drainage side, and the return pipe 35a is shut off (ST22). Then, the circulation pump 43 is turned on (ST23), the drain electromagnetic valve 54 of the drain pipe 52 is opened (ST24), and the remaining water in the drain tank 48 is discharged to the bathtub 40.
If 10 minutes have passed in this state (ST25), it is assumed that all the remaining water in the drainage tank 48 has been discharged, so the circulation pump 43 is turned off (ST26) and the two-way valve 41 is turned to the circulation side. Switch (ST27).
[0031]
After confirming that the empty flag is turned on (ST12) or performing a drain operation (ST21), there is no residual water in the drain tank 48, so the drain tank does not freeze. Therefore, in a state where the two-way valve 41 is positioned on the circulation side, the circulation pump 43 is turned on to circulate hot water in the bathtub 40 through the retrace line 35 to prevent freezing of the retrace line (ST13). .
Pump circulation in this anti-freezing operation continues until the temperature detected by the follow-up thermistor 44 reaches 4 degrees Celsius or higher, and when it reaches 4 degrees Celsius or higher (ST14), the circulation pump 43 is turned off.
In this case, the detected temperature of the thermistor 44a may be referred to instead of or in addition to the additional thermistor 44.
[0032]
Thus, according to the present embodiment, when turning on the circulation pump 43 in the freeze prevention operation, the presence or absence of residual water in the drain tank 48 provided in the hopper 45 is confirmed, and there is residual water in the drain tank 48. Since the drainage is performed, it is possible to prevent the drainage tank 48 from freezing by reliably draining the remaining water accumulated in the drainage tank 48 before the drainage tank 48 is frozen.
Further, by preventing the drainage tank 48 from freezing, it is possible to avoid water overflow to the separated air side, and it is possible to satisfactorily perform automatic hot water filling operation and the like.
[0033]
In addition, a heater may be attached to face the drain tank 48 of the hopper, and this heater may be driven based on the temperature detected by the thermistor 44 and / or the thermistor 44a.
[0034]
【The invention's effect】
As described above, according to the combined water heater of the present invention, the drainage tank can be prevented from freezing by surely draining the remaining water accumulated in the hopper drainage tank before freezing. Can do.
[Brief description of the drawings]
FIG. 1 is a flowchart showing an example of a freeze prevention operation by a composite water heater according to an embodiment of the present invention.
FIG. 2 is a flowchart for explaining in detail the drainage operation in FIG. 1;
FIG. 3 is a system diagram showing a main configuration of a composite water heater employed in the present embodiment.
FIG. 4 is an explanatory diagram showing a connection between a control unit and each element in the present embodiment.
FIG. 5 is a system diagram showing a state of hot water filling a bathtub in a conventional combined water heater.
FIG. 6 is a system diagram showing the state of air separation by a hopper in a conventional combined water heater.
FIG. 7 is a system diagram showing a state of discharging residual water accumulated in a drain tank in a conventional combined water heater.
FIG. 8 is a flowchart showing a freeze prevention operation in a conventional combined water heater.
[Explanation of symbols]
31 Combined Water Heater 32 Hot Water Heat Exchanger 33 Bath Heat Exchanger 34a Water Supply Pipe 34b Hot Water Supply Pipe 34 Hot Water Supply Pipe Line 35 Remaining Pipe Line (Circulation Line)
35a Return pipe 35b Outgoing pipe 36 Branch pipe 37 Water flow sensor 38a Inlet thermistor 38b Hot water supply thermistor 39 Water control part 40 Bath 40a Circulation fitting 41 Two-way valve 42 Mouth flow water switch 43 Circulation pump 44 Bath thermistor 45 Hopper 46 Pressure sensor 47 Note Water solenoid valve 48 Drain tank 49 Drain tank valve 50 Negative pressure shut-off valve 51 Check valve 52 Drain line 53 Check valve 54 Drain solenoid valve 55 Drain port 56 Water level switch

Claims (2)

A hot water supply pipe for heating and pouring hot water,
A hopper that separates air from a reheating pipeline that circulates and heats water or hot water in the bathtub;
A thermistor provided in the draining tank of the reheating pipe and / or the hopper,
When the detection temperature of the thermistor provided in the follow-up conduit and / or the hopper drain tank is equal to or lower than a predetermined temperature , the presence or absence of residual water in the hopper drain tank is confirmed,
Confirm that the inside of the drainage tank is empty, or if there is residual water in the drainage tank, drain the drainage tank to make the inside of the drainage tank empty,
A combined water heater characterized by turning on a circulation pump to circulate hot water in a bathtub to a follow-up pipeline. When the detected temperature of the thermistor is equal to or lower than a predetermined first temperature, the circulation pump is turned on,
The combined water heater according to claim 1 , wherein the circulation pump is turned off when the temperature becomes equal to or higher than a predetermined second temperature.

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