JPH11325597A - Combustion equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively avoid freezing of a water in a reheating circulating passage of a bathtub water. SOLUTION: Data of a temperature change with respect to a time of a retained water in an external piping 31 of a reheating circulating passage 23 of a bathtub water is previously given. A circulating pump 17 is driven at the time of a fear of freezing such as in winter or the like, a hot water of a bathtub 18 is circulated to the passage 23, and a water temperature in the passage 23 is detected by a bath temperature sensor 21 immediately before stopping of the pump 17. A pump waiting allowing time required to lower the water of an external piping to a water temperature immediately before the water is frozen from the detected water temperature is obtained based on the detected water temperature and the data. When a lapse time from the stop of the pump 17 arrives at the allowing time, the pump 17 is driven to prevent freezing of the water in the passage 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a combustion apparatus capable of reheating a bath.

[0002]

2. Description of the Related Art FIG. 6 shows an example of a system configuration of a one-can-two-water-channel type bath water heater which is a combustion device developed by the applicant. In the figure, a hot water supply heat exchanger 2 for performing a hot water supply function and a reheating heat exchanger 3 for performing a reheating function are integrally disposed in an appliance case 1. That is, a hot water supply water pipe is mounted on a plurality of common fin plates 4 to form a hot water supply heat exchanger 2. Has formed.

A burner 5 for heating the hot water supply heat exchanger 2 and the reheating heat exchanger 3 in common is disposed below these integrated heat exchangers. A combustion fan 6 to be operated is arranged below the burner. A gas passage 9 is connected to the burner 5. The gas passage 9 is connected to solenoid valves 7 and 8 for opening and closing the passage, and a proportional valve for controlling a gas supply amount (burner combustion heat amount) by a valve opening amount. 10 are interposed. The proportional valve 10
Is specifically controlled by variable control of the current (valve opening drive current) applied to the proportional valve 10.

[0004] A water supply pipe 11 serving as a water supply passage is connected to the inlet side of the hot water supply heat exchanger 2, and a water supply temperature for detecting a water supply temperature (water supply temperature) of the hot water supply heat exchanger 2 is connected to the water supply pipe 11. A detection sensor 12 and a flow rate detection sensor 13 for detecting a water supply (hot water supply) flow rate (a hot water flow rate in the case of hot water filling) are provided. The inlet side of the water supply pipe 11 is connected to a water pipe.

[0005] A hot water supply pipe 14 as a hot water supply passage is connected to the outlet side of the hot water supply heat exchanger 2, and the hot water supply pipe 14 is led to a desired hot water supply place such as a kitchen through an external pipe. A hot water supply temperature sensor 15 for detecting a hot water supply temperature is provided in a flow path on the outlet side of the hot water supply heat exchanger 2.

A line 1 is provided on the inlet side of the reheater 3.
6 is connected to one end, and the other end of the conduit 16 is connected to the discharge side of the circulation pump 17. And the circulation pump 1
7 is connected to one end of a return pipe 20, and the other end of the return pipe 20 is connected to a pair tube 31 which is an external pipe.
A bath temperature sensor 21 which is a circulation passage water temperature detecting means for detecting the temperature of the circulating hot and cold water in the bath tub 18 as a bath temperature is connected to the return pipe 20 via the (31a) and the return pipe 20, and detects flowing water. A flow sensor or a flow sensor (flow switch) 19 is provided.

An outgoing pipe 2 is provided at the outlet side of the reheater 3.
2 is connected to one end, and the other end of the outward pipe 22 is connected to the bathtub 18 via a pair tube 31 (31b), which is an external pipe. The return pipe 20 from the bathtub 18 via the pair tube 31a is circulated. The passage returning to the bathtub 18 via the pump 17, the pipeline 16, the reheating heat exchanger 3, the outgoing pipe 22, and the pair tube 31b constitutes a reheating circulation passage 23 in which bathtub hot water circulates.

The hot water supply pipe 14 of the hot water supply heat exchanger 2 and the additional heating circulation passage 23 (the pipe 16 in FIG. 6) are connected to each other by a hot water filling passage 24.
A pouring valve 25 constituted by an electromagnetic valve or the like for opening and closing the passage is interposed in 4, and a water level sensor for detecting the water level of the bathtub 18 by the water pressure in the hot water filling passage 24 downstream of the pouring valve 25. (Pressure sensor) 26 is provided.

The flow rate detecting sensor 13 and the temperature sensor 1
Sensor detection signals such as 2, 15, 21 and a water level sensor 26 are applied to a control device 27, and a remote control 28 is connected to the control device 27. The remote controller 28 has a hot water temperature setting means for setting a hot water temperature, a bath temperature setting means for setting a bath temperature, various operation buttons for commanding a hot water operation, an automatic operation, a reheating operation, a hot water operation,
A display unit or the like for displaying necessary information is provided.

The control device 27 fetches various sensor detection signals and information from the remote controller 28, and controls a hot water supply operation, a hot water filling operation, and a reheating operation according to a sequence program provided therein as follows.

For example, the faucet 30 of the hot water supply passage led to the kitchen or the like is opened and a predetermined hot water supply operation flow rate (for example, 2.5 liter / mi) at which the hot water supply operation can be started.
n) When the above-mentioned flow rate is detected by the flow rate detection sensor 13, the combustion fan 6 is rotated, the solenoid valves 7, 8 are opened, and fuel gas is supplied to the burner 5.
The burner 5 is burned by the ignition of an igniter (not shown), and the proportional valve 10 is opened so that the hot water temperature detected by the hot water temperature sensor 15 matches the hot water set temperature set by the remote controller 28. The drive current is controlled, and the water passing through the hot water supply heat exchanger 2 is heated by the flame of the burner 5 to produce hot water having a set temperature, and the hot water is supplied to the hot water supply location via the hot water supply pipe 14. Then, the faucet 30 is closed and the flow rate detection sensor 1
When the off signal is output from 3, the burner combustion is stopped, and the operation in the hot water supply operation mode ends.

When an automatic operation mode or a filling operation mode is commanded by the remote controller 28, the pouring valve 25 is opened. When the flow rate detection sensor 13 detects a flow rate equal to or higher than the above hot water supply operation flow rate, combustion of the burner 5 is started in the same manner as in the hot water supply operation, and hot water is produced by the hot water supply heat exchanger 2. The hot water is dropped into the bathtub 18 from both sides of the path passing through the hot water supply pipe 14 and the hot water filling passage 24, branching off from the pipe 16, passing through the heat exchanger 3, passing through the forward pipe 22, and passing through the return pipe 20. Be included. When the amount of hot water drops to the set water level or when the set water level is detected by the water level sensor 26, the pouring valve 25 is closed and the combustion of the burner 5 is stopped, and the operation in the filling operation mode is performed. Ends.

In the operation in the reheating operation mode, the circulation pump 17 is driven to rotate while the pouring valve 25 is closed, and the circulation of hot water in the bathtub 18 is performed through the reheating circulation passage 23 and the bath When the bath detection temperature detected by the temperature sensor 21 is lower than the bath set temperature, the burner 5 is burned in response to a running water ON signal from the flow rate sensor (running water sensor) 19, and the reheating circulation passage 23 is provided.
The hot and cold bath tub circulating through is heated by the heat exchanger 3. Then, when the bath temperature sensor 21 detects that the temperature of the bath water reaches the set bath temperature, the circulation pump 17 and the burner 5 are stopped, and the operation in the reheating operation mode ends. .

[0014]

Incidentally, in order to prevent the staying hot water in the reheating boiler circuit 23 from freezing in the winter season or the like, there are cases where the combustion equipment is provided with the following antifreezing function. is there. For example, an outside air temperature sensor 32 which is an outside air temperature detecting means for detecting an outside air temperature surrounding the combustion equipment is provided, and an outside air temperature Tg detected by the outside air temperature sensor 32 and a reheating cycle detected by the bath temperature sensor 21. The water temperature Th in the passage 23 is taken in every moment, and the detected outside air temperature Tg is set to a set outside air temperature threshold (for example, 2
° C), and the detected water temperature Th of the reheating recirculation passage 23 is equal to the set circulation passage water temperature threshold value (for example, 2
(° C.), it is determined that there is a risk that the water in the reheating circulation passage 23 may freeze, and the circulation pump 17 is driven to flow the water in the reheating circulation passage 23 to make the reheating circulation passage 23. Prevents the water in 23 from freezing.

However, since the pair tube 31 is exposed to the outside of the room, the temperature of the water retained in the pair tube 31 during the stop of the circulation pump 17 depends on the return pipe housed in the instrument case 1. It becomes lower than the water temperature of the portion of the reheating circulation passage 23 such as 20. The bath temperature sensor 21 detects the water temperature of the pipeline in the appliance case 1 and cannot directly detect the water temperature in the pair tube 31. Therefore, the water retained in the pair tube 31 reaches the temperature immediately before freezing. It is difficult to detect that the temperature has dropped on the basis of the detection value of the bath temperature sensor 21, and although the water retained in the pair tube 31 has dropped to the temperature immediately before freezing, the temperature of the bath temperature sensor 21 Since the detected water temperature is equal to or higher than the threshold temperature, the circulating pump 17 for preventing freezing is not driven, and the water retained in the pair tube 31 freezes, and the freezing causes damage to the pipeline. There was a possibility that a problem would occur.

In particular, in a single-can, two-channel type combustion apparatus as shown in FIG. 6, when the hot-water supply alone operation is performed, only the hot-water heat exchanger 3 is heated. The water temperature in the reheating circulation passage 23 in the exchanger 3 and in the vicinity thereof rises, while the water temperature in the pair tube 31 hardly rises even when the hot water supply alone operation is performed. Despite the fact that the temperature has dropped to the temperature just before the water is frozen, the bath temperature sensor 21
Is not lower than the circulation passage threshold,
For this reason, the circulation pump 17 is not driven and the pair tube 3 is not driven.
The probability that the problem that the water in 1 freezes will increase.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the invention is to reliably drive a circulation pump before water in an external piping portion of a reheating circulation passage is frozen. An object of the present invention is to provide a combustion device capable of preventing freezing of water in a reheating circulation passage.

[0018]

Means for Solving the Problems In order to achieve the above object, the present invention has the following structure to solve the above problems. That is, the first aspect of the present invention provides a reheating cycle path with a circulation pump for circulating bath water, a recirculation path water temperature detecting means for detecting a water temperature in the reheating path, and detecting an outside air temperature surrounding the combustion equipment. Anti-freezing for controlling the driving / stopping of the circulation pump based on predetermined freeze prevention pump driving conditions and pump stop conditions to prevent freezing of water in the reheating circulation passage. A combustion device having a function, wherein the water temperature in the reheating circulation passage detected by the circulation passage water temperature detection means during or immediately after the driving of the circulation pump, and the outside air temperature detected by the outside air temperature detection means And, after the circulation pump is stopped, by the data given in advance for obtaining the pump standby allowable time by combining the water temperature and the outside air temperature in the reheating circulation passage, A pump standby permissible time detecting unit for obtaining a pump standby permissible time until the circulation pump is driven before water in the boil circulation path is frozen; and the pump standby after the circulation pump is stopped based on the pump stop condition. When the pump standby allowable time detected by the allowable time detection unit has elapsed, the circulating pump is driven to prevent freezing of water in the reheating circulating passage even if the antifreeze pump driving condition is not satisfied. And a means for solving the above-mentioned problem.

According to a second aspect of the present invention, in addition to the configuration of the first aspect, a data storage unit for storing data of a pump standby allowable time; And when the detected allowable pump standby time for updating is shorter than the allowable pump standby time stored in the data storage unit, the allowable pump standby time of the data storage unit is set to And a pump standby permissible time updating unit that updates the pump standby permissible time for update;
The means for solving the above-mentioned problem is configured to perform drive control of the circulation pump based on the allowable pump standby time stored in the data storage unit.

According to a third aspect of the present invention, in the second aspect of the present invention, the pump standby permissible time updating section includes a reheating circulation passage detected by the circulation passage water temperature detecting means during or immediately after the previous operation of the circulation pump. A means for solving the above-mentioned problem has a configuration in which an update operation of the pump standby allowable time is performed based on a water temperature in the inside and an operation of updating the pump standby allowable time is performed.

According to a fourth aspect of the present invention, there is provided the first, second or third aspect.
In addition to the configuration of the invention, a predetermined temperature detection timing interval is provided during the operation of the circulation pump or immediately after the circulation pump is stopped after the circulation pump water temperature is detected by the circulation passage water temperature detection means. The circulation pump is forcibly driven in time, the water temperature in the reheating circulation passage is detected by the circulation passage water temperature detecting means, and the detected water temperature of the reheating circulation passage and the water temperature of the previously detected reheating circulation passage are detected. A temperature deviation detecting unit for detecting a deviation from the temperature of the combustion pump; data for estimating and detecting an outside air temperature surrounding the combustion equipment based on a temporal temperature change of water in the reheating circulation passage when the circulation pump is stopped. , The data, and the water temperature deviation of the reheating circulation passage detected by the temperature deviation detection unit,
Based on the timing interval time of the temperature deviation detection unit,
And an outside air temperature estimation detecting section for estimating and detecting the outside air temperature surrounding the combustion device, wherein the pump standby allowable time detecting section is replaced by the outside air temperature estimation detecting section instead of the outside air temperature detected by the outside air temperature detecting means. The above-mentioned problem is solved by a configuration in which the estimated standby air temperature is used to determine the allowable pump standby time.

According to a fifth aspect of the present invention, there is provided the configuration according to any one of the first to fourth aspects, wherein the outside air temperature detected by the outside air temperature detecting means is lower than a set outside air temperature threshold value. When, or when the water temperature of the reheating circulation passage detected by the circulation passage water temperature detection means falls below the set circulation passage water temperature threshold, the circulation pump is forcibly determined as the freezing prevention pump driving condition is satisfied. A means for solving the above-mentioned problem is provided by a configuration in which a freezing prevention control unit for preventing freezing of water in the reheating circulation passage by being driven in a specific manner is provided.

In the invention having the above-mentioned structure, for example, when the driving condition of the freezing prevention pump is satisfied and the driving of the circulation pump is started, the bathtub hot water circulates in the reheating combustion circulation passage. The water temperature is substantially uniform over the entire area. During or immediately after the circulation pump is driven, the outside air temperature surrounding the combustion equipment is detected by the outside air temperature detection means, and the water temperature in the reheating circulation passage is detected by the circulation passage water temperature detection means. As described above, since the water temperature is substantially uniform over the entire area in the reheating circulation passage, the water temperature detected by the circulation passage water temperature detecting means can be regarded as the water temperature of the external piping portion of the reheating circulation passage. It is.

The pump standby permissible time detector detects the pump standby permissible time based on a combination of the detected water temperature of the reheating circulation passage, the outside temperature detected by the outside air temperature detecting means, the water temperature of the reheating circulation passage, and the outside air temperature. Based on the data for determining the temperature, the time during which the water in the external pipe is reduced from the detected water temperature to the temperature immediately before freezing in a state where the external pipe is exposed to the detected external air temperature is allowed to be on standby for the pump. Calculate as time.

The anti-freezing pump drive control section determines whether the anti-freezing pump driving condition is not satisfied when the above-mentioned allowable pump standby time has elapsed since the circulation pump was stopped based on the anti-freezing pump stopping condition. By driving the circulation pump, the water in the recirculation passage is made to flow to prevent freezing.

As described above, the circulation pump is driven based on the permissible pump standby time in consideration of the cooling speed of the stagnant water in the external piping that is most liable to freeze in the reheating circulation passage. Can flow, so that the problem that water in the external piping freezes can be avoided. That is, freezing of water in the reheating circulation passage can be reliably prevented.

[0027]

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

The combustion apparatus shown in the first embodiment has the system configuration of the combustion apparatus shown in FIG. 6, and is characterized by the fact that the portion of the pair tube 31 which is most easily frozen in the reheating circulation passage 23 is formed. That is, a control structure capable of reliably preventing freezing of water is provided. In the description of this embodiment, the description of the system configuration of the combustion equipment shown in FIG.

FIG. 1 shows a characteristic control configuration in the first embodiment by solid lines. The control device 27 according to the first embodiment includes a pump standby allowable time updating unit 35, a pump standby allowable time detecting unit 36, a timer 37, a data storage unit 40, and a pump driving unit, as indicated by solid lines in FIG. 41, an antifreeze pump drive control unit 42 and an antifreeze control unit 43.

The anti-freezing control section 43 is given in advance the driving conditions for the anti-freezing pump and the conditions for stopping the pump. The anti-freezing control section 43 controls the inside of the reheating circulation passage 23 detected by the bath temperature sensor 21. The water temperature Th and the outside air temperature Tg detected by the outside air temperature sensor 32 are fetched from time to time, and the driving / stopping of the circulation pump 17 is performed based on the fetched detection values, and the above-described freezing prevention pump driving conditions and pump stop conditions. Control.

In this embodiment, the following two conditions are given as the above-described freezing prevention pump driving conditions. The first condition is when the water temperature Th in the additional heating circulation passage 23 detected by the bath temperature sensor 21 falls below a set circulation passage threshold value Thstart (for example, 8 ° C.), and the second condition Is an external air temperature threshold Tgstart (for example, the external air temperature Tg detected by the external air temperature sensor 32)
7 ° C.).

The threshold value of the circulation passage Thstart and the threshold value of the outside air temperature Tgstart are stored in advance in a data storage unit 40 as a storage device. Since the detected water temperature of the bath temperature sensor 21 during the stoppage of the circulation pump 17 is higher than the water temperature in the pair tube 31, in a state where the outside air temperature around the combustion equipment is reduced to a temperature at which the water freezes, The deviation of the water temperature in the pair tube 31 with respect to the water temperature detected by the bath temperature sensor 21 while the circulation pump is stopped is determined by experiment, calculation, or the like, and taking into account the deviation of the water temperature, the freezing in the reheating circulation passage 23 is most easily performed. The circulation passage threshold value Thstart for driving the circulation pump 17 before the water in the pair tube 31 is frozen is obtained and given.

Further, since the outside air temperature sensor 32 is provided in the appliance case 1, the outside air temperature detected by the outside air temperature sensor 32 is higher than the outside air temperature around the pair tube 31. The deviation of the outside air temperature around the pair tube 31 with respect to the outside air temperature detected by the outside air temperature sensor 32 is obtained by an experiment, calculation, or the like, and the outside air temperature threshold Tgstart is obtained in consideration of the deviation of the outside air temperature. .

The anti-freezing control unit 43 compares the taken-in water temperature Th of the bath temperature sensor 21 and the detected outside air temperature Tg of the outside air temperature sensor 32 with the corresponding circulation passage threshold Thstart and the outside air temperature in the data storage unit 40, respectively. In comparison with the threshold value Tgstart, it is determined whether the detected value is lower than the threshold value. Based on the determination result, it is determined that at least one of the first condition and the second condition is satisfied. Sometimes, it is determined that the freeze prevention pump drive condition is satisfied, and a drive command for the circulation pump 17 is issued to the pump drive unit 41.
The pump drive unit 41 drives the circulation pump 17 in response to the drive command. In this way, by driving the circulation pump 17, the water in the reheating circulation passage 23 is made to flow to prevent freezing of the water in the reheating circulation passage 23.

In this embodiment, when the detected water temperature Th of the bath temperature sensor 21 rises above a set stop temperature Thstop (for example, 9 ° C.), the pump stop condition is given in advance. The stop temperature Thstop is stored in the data storage unit 40 in advance, and the anti-freezing control unit 43 continuously captures the detected water temperature Th of the bath temperature sensor 21 every moment even after the circulation pump 17 is driven for anti-freezing, The detected water temperature Th is compared with the stop temperature Thstop of the data storage unit 40, and the detected water temperature T
When it is determined that h has risen above the set stop temperature Thstop, it is determined that the pump stop condition has been satisfied, and there is no fear of freezing due to the bathtub hot water circulating in the recirculation passage 23 by driving the circulation pump 17. Since the bath water having the water temperature fills the inside of the reheating circuit 23, the reheating circuit 2
It is determined that the risk of freezing of the water in 3 has disappeared, and a stop command for the circulation pump 17 is issued to the pump drive unit 41. The pump drive unit 41 receives the stop command and stops the circulation pump 17.

The pump standby allowable time detecting section 36 fetches the operation information of the freeze prevention control section 43 from time to time, and when it detects that the drive of the circulation pump 17 by the freeze prevention control section 43 stops based on the information. Immediately before the circulation pump 17 stops, the outside air temperature sensor 32 detects the outside air temperature Tg, and the bath temperature sensor 21 detects the water temperature Th in the reheating circulation passage 23. At this time, the bath water is circulated in the reheating circulation passage 23 by the drive of the circulation pump 17, and the water temperature is substantially uniform over the entire area in the reheating circulation passage 23. The performed water temperature can be regarded as the water temperature in the pair tube 31.

The data storage unit 40 has a reheating circulation passage 2
The standby time detection data for obtaining the pump standby allowable time tz based on the combination of the detected water temperature Th and the detected outside air temperature Tg within the range 3 is given in advance. The pump standby allowable time tz is the time from when the driving of the circulating pump 17 is stopped based on the freeze stopping pump stopping condition to when the circulating pump 17 is driven just before the water in the pair tube 31 freezes. That is. That is, in this embodiment, when the atmosphere surrounding the combustion device (pair tube 31) is the outside temperature Tg, the water in the pair tube 31 drops from the water temperature Th to the temperature immediately before freezing (for example, 1 ° C.). The time until the pump standby time is set as the pump standby allowable time tz.

The present inventors varied the outside air temperature Tg and the cooling start water temperature Th in the paired tube 31 in various ways, and obtained the temporal change of the water temperature in the paired tube 31 by experiments. FIG. 4 shows an example of the experimental result. FIG.
Represents a change in water temperature in the pair tube 31 for each outside air temperature when the water temperature at the start of cooling in the pair tube 31 is fixed at 40 ° C., and the solid curve L1 indicates a case where the outside air temperature is −20 ° C. Represents the temporal change of the water temperature in the pair tube 31 of FIG.
A time curve of the water temperature in the pair tube 31 when the temperature is 0 ° C. is shown, and a solid curve L3 shows a time change of the water temperature in the pair tube 31 when the outside air temperature is −5 ° C. The solid line curve L4 represents the temporal change of the water temperature in the pair tube 31 when the outside air temperature is 0 ° C.

Based on the above experimental results, the present inventors have determined the above by combining the detected water temperature Th of the bath temperature sensor 21 detected immediately before the stop of the circulation pump 17 and the detected outside air temperature Tg of the outside air temperature sensor 32. The operation formula data as shown in the following equation (1) for obtaining the pump standby allowable time tz could be derived. In this embodiment, the derived arithmetic expression data is stored in the data storage unit 40 as standby time detection data.

Tz = (((Tg−α) +440) × (Th + 359) / 115) −600 (1)

Α in the above equation (1) is the detected outside air temperature T detected by the outside air temperature sensor 32 with respect to the outside air temperature surrounding the combustion equipment.
g is a constant representing a temperature shift of, for example, a constant of 8 ° C. is given in advance. In the above equation (1), Tg represents an outside air temperature parameter around the pair tube 31, Th represents a water temperature parameter in the pair tube 31 at the start of cooling, and the above Tg and Th are units of degrees Celsius. The allowable pump standby time tz calculated by the above equation (1) is a time unit of seconds.

The pump standby allowable time detecting section 36 stores the detected water temperature Th of the bath temperature sensor 21 and the detected outside air temperature Tg of the outside air temperature sensor 32 taken immediately before the stop of the circulation pump 17 in the data storage section 40 as described above. The allowable pump standby time tz is determined by substituting the predetermined parameter of the standby allowable time detection data into the predetermined parameter, and the determined allowable pump standby time t
z is stored in the data storage unit 40. Further, the pump standby allowable time detecting unit 36 stores the detected water temperature Th of the bath temperature sensor 21 taken immediately before the stop of the circulation pump 17 in the data storage unit 40.

The antifreeze pump drive control section 42 fetches the operation information of the antifreeze control section 43 from time to time, and based on the operation information, the antifreeze control section 43 causes the circulating pump 17 to operate.
When it is determined that the driving of the timer 37 has been stopped, the driving of the timer 37 is started. The timer 37 measures the elapsed time from when the driving of the anti-freezing pump is stopped.

After starting the operation of the timer 37 as described above, the anti-freeze pump drive control unit 42 monitors the measurement time of the timer 37, and the measurement time tc of the timer 37 is stored in the data storage unit 40. It is determined whether or not the measured time tc has reached the pump standby allowable time tz, as compared with the pump standby allowable time tz. When the drive of the circulation pump 17 is started by the freeze prevention control unit 43 before the measurement time tc reaches the pump standby allowable time tz, the freeze prevention pump drive control unit 42 stops and resets the timer 37.

The anti-freezing pump drive control unit 42
The time tc measured by the timer 37 is the allowable pump standby time t.
When it is determined that z has been reached, before the circulating pump 17 is driven by the anti-freezing control unit 43, that is, although the above-described anti-freezing pump driving condition is not satisfied,
Since there is a possibility that the temperature of the water in the pair tube 31 has dropped to just before freezing, it is determined that the circulation pump 17 needs to be driven in order to prevent the water in the pair tube 31 from freezing. Issues a pump drive command to the unit 41,
The circulation pump 17 is forcibly driven by the pump drive unit 41. The antifreeze pump drive control unit 42 stops and resets the timer 37 after the measured time tc of the timer 37 reaches the allowable pump standby time tz.

After the circulation pump 17 is forcibly driven by the antifreeze pump drive control unit 42, the stoppage of the circulation pump 17 is controlled by the antifreeze control unit 43. As described above, the allowable pump standby time tz is detected by the allowable pump standby time detector 36 as described above.

As described above, after the permissible pump standby time tz is detected by the permissible pump standby time detector 36, the outside air temperature around the pair tube 31 decreases, and the cooling speed of the water in the pair tube 31 decreases. May be hastened. Normally, the outside air temperature around the pair tube 31 does not drastically decrease and fluctuate. Therefore, even if the pump standby allowable time tz is not changed in the direction of shortening the pump standby allowable time tz according to the above-mentioned outside air temperature fluctuation, the pair tube 31 does not change. We can almost certainly achieve the prevention of water freezing, but here,
In order to achieve more safety, the pump standby allowable time tz is changed according to the change in the outside air temperature drop during the stop of the circulation pump 17.
Is provided in the control system to change the length in the direction of shortening.

The allowable pump standby time updating unit 35 has a built-in timer (not shown) in which a time interval for obtaining the allowable pump standby time tz 'for updating is set. Pump standby allowable time detecting unit 36
While the circulating pump 17 is detected as being stopped after the allowable pump standby time tz is detected by the allowable pump standby time detection unit 36 based on the information. The external temperature Tg detected by the external temperature sensor 32 is captured at each timing set by the built-in timer, and the captured detected external temperature Tg is captured.
And the circulation pump 17 stored in the data storage unit 40
Based on the detected water temperature Th in the reheating circulation passage 23 detected immediately before the stop and the standby allowable time detection data,
The pump waiting allowable time tz 'for updating is detected.

The pump standby allowable time updating unit 35 compares the update pump standby allowable time tz ′ with the pump standby allowable time tz of the data storage unit 40 every time the update pump standby allowable time tz ′ is detected. And the pump standby allowable time tz
When it is determined that the allowable pump standby time tz 'for update is shorter than that, the external temperature around the pair tube 31 is determined to have decreased, and the allowable pump standby time tz is changed in accordance with the fluctuation in the decrease in the external temperature. When it is determined that it is necessary, the allowable pump standby time tz in the data storage unit 40 is updated to the allowable pump standby time tz 'for updating.

As described above, after the allowable pump standby time tz is updated, the antifreeze pump drive control unit 42 sets the pair tube 31 (the additional heating circulation passage 23) based on the updated allowable pump standby time tz. Perform water freezing prevention operation.

The control structure for preventing freezing in the first embodiment is configured as described above, and an example of the control operation for preventing freezing will be described below with reference to the flowcharts of FIGS. 2 and 3. .

First, when the reheating operation is not being performed, it is determined whether or not the hot water supply operation (here, all operations for making hot water by the hot water supply heat exchanger 2 are collectively referred to as a hot water supply operation) is stopped. When it is determined that the hot water supply operation is being performed (step 101), the apparatus stands by in that state, and when it is determined that the hot water supply operation is stopped, the freeze prevention pump drive control unit 42 or the freeze prevention control unit 43 It is determined whether the freeze prevention pump is driven by the control (step 102). If it is determined in step 101 that the hot water supply operation is being performed, and the timer 37 is being driven, the count of the timer 37 is increased by one step.

If it is determined that the freeze prevention pump has not been driven, and the timer 37 has been driven,
The count of the timer 37 is increased by one step (step 103), and the data storage unit 40 stores the allowable pump standby time tz.
Is stored, the count time tc of the timer 37 is compared with the pump standby allowable time tz of the data storage unit 40, and whether the count time tc is smaller than the pump standby allowable time tz is determined. Is determined (step 104).

When the timer 37 is not driven, the count-up operation in the step 103 and the judgment operation in the step 104 are not performed. After that, the water temperature Th detected by the bath temperature sensor 21 is taken in, and The acquired detected water temperature Th is compared with the circulation passage water temperature threshold value Thstart stored in the data storage unit 40, and it is determined whether the detected water temperature Th is lower than the circulation passage threshold value Thstart (step 105). By this determination operation, when it is determined that the detected water temperature Th is lower than the circulation passage threshold Thstart, the water temperature in the reheating circulation passage 23 is low,
The water in the reheating circulation passage 23, in particular, the pair tube 31
It is determined that there is a risk of freezing of the water in the
Starts the operation of the circulation pump 17 (step 10).
6).

After starting the freezing prevention pump drive,
The operation after step 101 is repeatedly performed. In the determination operation of step 102, it is determined that the circulating pump 17 for freezing prevention is being driven because the pump for freezing prevention is being driven as described above. The detected water temperature Th of the bath temperature sensor 21 is taken in, the detected water temperature Th is compared with the pump stop temperature Thstop, and it is determined whether the detected water temperature Th is higher than the pump stop temperature Thstop (step 10).
7). While the anti-freezing pump is being driven, the detected water temperature Th of the bath temperature sensor 21 is taken in at set time intervals, and the determination operation of step 107 is repeated, whereby the detected water temperature Th becomes the pump stop temperature Thstop.
While it is determined that the temperature is below, there is a possibility that the water in the additional heating circulation passage 23 is frozen. Therefore, the drive of the circulation pump 17 is continued to prevent the water in the additional heating circulation passage 23 from freezing.

In step 107, the detected water temperature T
When it is determined that h has become higher than the pump stop temperature Thstop, the entire area of the reheating circulating passage 23 is filled with bath water having a water temperature free from concern about freezing. At this time, it is determined that there is no possibility of freezing, and at this time, the pump standby allowable time detecting unit 36 detects the additional heating circulation passage 23 detected by the bath temperature sensor 21.
And the water temperature in the pair tube 31,
It takes in the outside air temperature Tg detected by the outside air temperature sensor 32, reads out the data for detecting the allowable standby time stored in the data storage unit 40, and reads out the detected value Th,
Based on Tg and the data for detecting the allowable standby time, the time required for the water in the pair tube 31 to be exposed to the outside temperature Tg, cooled, and lowered from the water temperature Th to the temperature immediately before freezing is set as the allowable pump standby time tz. The data of the calculated allowable pump standby time tz and the data of the detected water temperature Th used for calculating the allowable pump standby time tz are stored in the data storage unit 40 (step 108).

After the calculation of the allowable pump standby time tz, the freeze prevention control unit 43 stops driving the circulation pump 17 (step 109).

Then, the operation after step 101 is repeated again. In the judgment operation of step 102, it is determined that the driving of the anti-freezing pump is stopped, and the count of the timer 37 is increased by one step. The measurement of the elapsed time from the stop of the driving of the pump for prevention is started.

Next, since the data of the permissible pump standby time tz is stored in the data storage section 40, the judgment operation of the step 104 is performed. That is, the timer 37
Is compared with the allowable pump standby time tz of the data storage unit 40 to determine whether the measured time tc has reached the allowable pump standby time tz. As a result of this determination, the measured time tc of the timer 37 becomes the pump standby allowable time t
If it is determined that z has not reached z, the allowable pump standby time updating unit 35 calculates an allowable pump standby time tz 'for updating (step 110).

That is, the detected water temperature Th of the bath temperature sensor 21 stored in the data storage section 40 is read, and the outside air temperature Tg detected by the outside air temperature sensor 32 is fetched. Based on the data for time detection, an allowable pump standby time tz ′ for updating is calculated.

Then, the allowable pump standby time tz stored in the data storage section 40 is read out, and the difference value (tz−tz−) obtained by subtracting the above-described calculated pump standby allowable time tz ′ from the pump standby allowable time tz. tz ')
It is determined whether or not it is equal to or greater than zero, that is, whether or not the allowable pump standby time tz 'for updating is shorter than the allowable pump standby time tz (step 111), and the difference value is smaller than zero. , The allowable pump standby time tz 'for updating
Is not shorter than the allowable pump standby time tz, the outside air temperature around the pair tube 31 is almost equal to the external air temperature when the allowable pump standby time tz is detected, and it is necessary to change the allowable pump standby time tz. It is determined that there is not, and the operation after step 105 is repeated without updating the allowable pump standby time tz.

Further, according to the judgment operation of the above step 111, the difference value (tz−tz ′) is zero or more,
When it is determined that the update allowable pump standby time tz ′ is shorter than the allowable pump standby time tz, the allowable pump standby time detecting unit 36 sets the allowable pump standby time tz of the data storage unit 40 to the allowable pump standby time tz. 'To update
The operation after step 105 is repeated.

If it is determined in step 105 that the water temperature Th detected by the bath temperature sensor 21 is equal to or higher than the circulation passage threshold value Thstart while the circulation pump 17 is stopped, then the freeze prevention pump drive control unit 42 It is determined whether or not the measured time tc of the timer 37 is shorter than the allowable pump standby time tz (step 113), and the measured time tc of the timer 37 is determined.
When it is determined that has not reached the pump standby allowable time tz, the outside air temperature Tg detected by the outside air temperature sensor 32 is further taken in, and whether or not the detected outside air temperature Tg is lower than the outside air temperature threshold Tgstart is determined. Judge (Step 11
4).

The detected outside air temperature Tg is equal to the outside air temperature threshold Tgstart.
When it is determined that the above is the case, as described above, the pump standby allowable time tz has not elapsed since the previous drive of the circulation pump 17 was stopped, and the detected water temperature Th of the bath temperature sensor 21 is not circulated. Since the outside temperature Tg detected by the outside temperature sensor 32 is not less than the threshold value Tgstart and the outside temperature Tg detected by the outside temperature sensor 32,
It is determined that the water in the inside does not freeze, and the operation after step 101 is repeated while the circulation pump 17 is stopped.

If it is determined that the detected water temperature Th is lower than the circulation passage threshold Thstart while the circulation pump 17 is stopped, the water in the reheating circulation passage 23 may be frozen. Is determined to exist, and as described above, the circulating pump 17 is
Drive.

Even if it is determined in step 105 that the detected water temperature Th is equal to or higher than the circulation passage threshold value Thstart, the circulation pump 17 is determined based on the measured time tc of the timer 37 in step 113. Is stopped, the anti-freezing pump drive control unit 42 determines that there is a risk of freezing in the water in the reheating circulation passage 23 (pair tube 31). In step 106, the circulation pump 17 is driven. Further, even if the detected water temperature Th is equal to or higher than the circulation passage threshold value Thstart as described above, and the elapsed time Tc after the stop of the circulation pump 17 has not reached the pump standby allowable time tz, the determination operation of the step 114 is performed. When it is determined that the detected outside air temperature Tg is lower than the outside air temperature threshold value Tgstart, it is determined that the water in the reheating circulation passage 23 may be frozen, and the anti-freezing control unit 43 In step 106, the drive of the circulation pump 17 is started,
The freezing of the water in the reheating circulation passage 23 is prevented.

As described above, after the freezing prevention pump drive control unit 42 or the freezing prevention control unit 43 starts driving the freezing prevention circulating pump 17, the operations after step 101 are repeated again.

While the above operation is being performed,
After the drive of the circulating pump 17 for preventing freezing is started, a pump drive control operation as shown in the flowchart of FIG. 3 is also performed.

First, as described above, the reheating circulation passage 2
It is determined that there is a risk of freezing of water in
Is started (step 201), a timer X (not shown) and a timer Y (not shown) built in the pump driving section 41 are reset (step 202). Thereafter, the count of the timer X is increased by one step, and the measurement of the elapsed time after the driving of the circulation pump 17 is started (step 203).

Then, it is determined based on the sensor signal of the flowing water sensor 19 whether or not water is detected in the reheating circulation passage 23 by driving the circulation pump 17 (step 20).
4) When it is determined that the water flow is not detected, the reset state of the timer Y is confirmed (step 21).
0), based on the time measured by the timer X, the circulation pump 17
Has been driven for a predetermined time (for example, 1
(0 minutes) is determined (step 211).
When it is determined that the elapsed time from the start of the pump drive has not reached the predetermined time, the operation after step 203 is repeated.

If it is determined in step 204 that the flow-on signal of the flowing water sensor 19 has been output and that the flow of the reheating circulation passage 23 by the driving of the circulation pump 17 has been detected, the timer Y Is increased by one step, and measurement of the elapsed time from the detection of water flow is started (step 205). Next, based on the time measured by the timer Y, the time elapsed since the passage of water through the reheating circulation passage 23 is detected for a predetermined time (for example, one minute).
Is determined (step 206), and when it is determined that the elapsed time from the detection of water passage has not reached the predetermined time, the operation after step 203 is repeated.

Then, in a state in which the flow of water in the reheating circulation passage 23 is continuously detected, it is determined in the determination operation in step 206 that the elapsed time from the detection of the flow of water has reached the predetermined time. Further, when it is confirmed that water flow in the reheating circulation passage 23 is detected (steps 207 and 212), it is determined that the bath water is circulating in the reheating circulation passage 23 stably. , The driving of the circulation pump 17 is continued.

As described above, in the state where the circulation pump 17 is normally driven and the bathtub water is circulating in the reheating circulation passage 23, the stop command of the circulation pump 17 is issued by the freeze prevention control unit 43 as described above. It is determined whether or not it has been issued (step 208). If it is determined that a command to stop the circulation pump 17 has been issued, the circulation pump 17 is stopped (step 209).

Also, in the judgment operation of the above-mentioned step 208,
When it is determined that the stop command of the circulation pump 17 has not been issued, it is further determined whether or not the operation of the combustion equipment other than the antifreeze operation is started (step 213). When it is determined that the operation is started, the circulation pump 17 is stopped (step 2).
09).

Also, in the judgment operation of step 211,
When it is determined that the elapsed time from the start of the pump drive has reached the above-described predetermined time, even if the circulating pump 17 is driven for the predetermined time, the passage of water through the reheating circulating passage 23 is not detected. It is determined that there is no hot or cold water in the bathtub 18, and from this, it is assumed that there is no water in the additional heating circulation passage 23. Therefore, there is no problem of freezing of water in the additional heating circulation passage 23. If the operation of the circulation pump 17 is continued, problems such as the heat generation of the circulation pump 17 occur, so the driving of the circulation pump 17 is stopped (step 209).

As described above, the circulation pump 1 for preventing freezing
After the driving of Step 7 stops, Step 101 in FIG.
The following operation is performed, and the anti-freezing operation is continued.

According to this embodiment, the time required for the temperature of the water in the pair tube 31 to decrease to a temperature immediately before freezing after the drive of the circulating pump 17 for preventing freezing is stopped is determined to allow the pump to stand by. This is given as time tz, and after the circulation pump 17 stops, the pump standby allowable time t
z, the circulation pump 17 is forcibly driven, so that the detected water temperature Th of the bath temperature sensor 21 is lower than the circulation passage threshold value Thstart, or the detected outside air temperature of the outside air temperature sensor 32. Not only when Tg is lower than the outside temperature threshold value Tgstart and the antifreeze pump driving condition is satisfied, but also when the antifreezing pump driving condition is not satisfied, the pump standby allowable time tz is set. And when it is assumed that the water temperature in the pair tube 31 has decreased to the temperature immediately before freezing based on the elapsed time from the stop of the pump, the circulation pump 17 can be driven. Since the bathtub hot water circulates in the reheating circulation passage 23, the freezing of the water in the pair tube 31 which is most easily frozen in the reheating circulation passage 23 is reliably avoided. Door can be.

In particular, in the case of a one-can, two-channel type combustion device,
As described above, when the burner 5 is burned by the hot water supply alone operation, the stagnant water in the reheating heat exchanger 3 is also heated, and the water temperature in the area near the reheating heat exchanger 3 increases. Although the temperature in the case 1 rises, the pump drive condition is not easily satisfied despite the fact that the temperature in the outer pair tube 31 drops to a temperature at which the water in the outer pair tube 31 freezes. As shown in the embodiment, the time from when the circulation pump 17 is stopped to when the temperature of the water in the pair tube 31 drops to the temperature immediately before freezing (the pump standby allowable time tz) is estimated, and the time from when the pump is stopped is estimated. By forcibly driving the circulation pump 17 when the elapsed time reaches the pump standby allowable time tz, even if the pump driving condition is not satisfied, the pair tube 31 can be used.
The circulation pump 17 can be driven before the water in the inside freezes, and the freezing problem can be avoided reliably. As described above, the freezing avoiding means shown in this embodiment is a very effective means as a freezing problem avoiding means in a one-can two-channel type combustion device.

In this embodiment, after the driving of the freezing prevention pump is stopped, the renewable pump standby allowable time tz 'is detected every moment, and the renewal pump standby allowable time tz' is determined. When the pump standby allowable time tz is shorter than the pump standby allowable time tz, the pump standby allowable time tz is updated to the update pump standby allowable time tz ′. Thus, the freezing of the water in the pair tube 31, that is, the reheating circulation path 23 can be reliably prevented.

That is, when the outside air temperature around the pair tube 31 is lower than the outside air temperature around the pair tube 31 when the pump standby allowable time tz is detected, the water inside the pair tube 31 is reduced due to the decrease in the outside air temperature. Of the pair tube 31 is reduced, the water in the pair tube 31 is allowed to stand for the pump standby allowable time tz detected when the circulation pump 17 is stopped.
Although it is conceivable that the temperature drops immediately before freezing in a shorter period of time, as described above, in this embodiment, the detected outside air temperature Tg of the outside air temperature sensor 32 which is taken in every moment.
, An allowable pump standby time tz 'for update is detected, and when the outside air temperature Tg decreases, the allowable pump standby time tz is updated to the allowable pump standby time tz' for update. Since the allowable time tz is set, and the pump drive control for preventing freezing is performed based on the pump standby allowable time tz and the measurement time tc of the timer 37, the pair tube is controlled regardless of the fluctuation in the outside air temperature. Freezing of the water in 31, that is, freezing of the water in the reheating circulation passage 23 can be reliably avoided.

Further, conventionally, the first condition that the water temperature detected by the bath temperature sensor 21 falls below the circulation passage threshold value, and the outside temperature detected by the outside air temperature sensor 32 falls below the circulation passage threshold value If both of the second condition, that is, the case where the first condition and the second condition are satisfied, the pump drive for preventing freezing is not performed, but in this embodiment, one of the first condition and the second condition is satisfied. When the condition is satisfied, a pump for freezing prevention is driven, so that freezing can be more reliably prevented.

Hereinafter, a second embodiment will be described. What is characteristic in the second embodiment is that the outside air temperature surrounding the combustion equipment is estimated and detected, and instead of the outside air temperature detected by the outside air temperature sensor 32, the pump standby allowable time is based on the estimated outside air temperature. That is, a configuration for obtaining tz is provided. The other configuration is the same as that of the first embodiment, and the description of the common parts will not be repeated.

As shown in FIG. 5, the combustor is installed indoors, but the pair tube 31 may be routed outside and connected to the bathtub 18. In such a case, it is very difficult for the outside air temperature sensor 32 provided in the appliance case 1 to detect the outside air temperature surrounding the pair tube 31, and the water staying in the pair tube 31 circulates before freezing. It is difficult to accurately determine the allowable pump standby time tz for driving the pump 17 based on the detection value of the outside air temperature sensor 32. Therefore, in this embodiment, a configuration is provided in which the outside air temperature surrounding the pair tube 31 is estimated and detected, and freezing of the water retained in the pair tube 31 can be reliably avoided.

The control device 27 shown in the second embodiment
Has a temperature deviation detection unit 44 and an outside air temperature estimation detection unit 45 as shown by a dotted line in FIG. 1 in addition to the control configuration shown in the first embodiment shown by a solid line in FIG. It is configured.

The temperature deviation detecting section 44 includes a deviation calculating section 46, a temperature capturing section 47, and a temperature detecting forced pump driving section 48, as shown by a dotted line in FIG. The temperature detection forced pump drive unit 48 has a configuration for forcibly driving the circulation pump 17 at a predetermined temperature detection timing. For example, at 0:00 am when it is assumed that bathing has ended, the timing for cooling start temperature detection is
Further, 4:00 a.m., at which the temperature is expected to drop considerably, is determined as the comparison temperature detection timing, and data of these timings is stored in the data storage unit 40.

When the temperature detection forced pump drive section 48 determines by the clock mechanism (not shown) of the remote controller 28 that it is the time for the cooling start temperature detection timing,
After confirming that a combustion operation such as reheating or hot water supply is not being performed, a pump drive command is issued to the pump drive unit 41, and the pump drive unit 41 forcibly drives the circulation pump 17 for a predetermined time. Let it.

The temperature take-in section 47 takes in the operation information of the temperature detection forced pump drive section 48 every moment, detects that the drive of the cooling start temperature detection pump has been started based on the information, and reheats the bathtub hot water. After it is determined that the water has circulated sufficiently in the circulation passage 23, the temperature detected by the bath temperature sensor 21 is taken as the water temperature in the pair tube 31 at the start of cooling, and the taken temperature data is stored in the data storage unit 40. I do.

When the clock mechanism of the remote controller 28 determines that the time for the comparison temperature detection has been reached, the temperature detection forced pump drive section 48 forcibly sets the circulation pump 17 in the same manner as described above. Drive for hours. The temperature capturing unit 47 detects the start of the comparison temperature detection pump drive based on the operation information of the temperature detection forced pump drive unit 48, and the bath temperature sensor 2
The monitoring of the detected water temperature fluctuation of 1 is started. While the circulation pump 17 is stopped, the temperature of the pair tube 31 in the reheating circulation passage 23 is the lowest, so the temperature intake unit 47 detects the temperature based on the monitoring result of the detected water temperature fluctuation. Detected water temperature Th in the area where the water temperature is the lowest
Is detected as the water temperature in the pair tube 31, and the detected temperature is output to the deviation calculating unit 46 as a comparison temperature.

When receiving the comparison temperature data, the deviation calculation unit 46 reads the cooling start temperature data stored in the data storage unit 40, and subtracts the comparison temperature from the cooling start temperature to store the data in the pair tube 31. The temperature decrease deviation ΔT from the start of water cooling is calculated, and data of the calculated temperature deviation ΔT is output to the outside air temperature estimation detection unit 45.

The data storage unit 40 stores a predetermined time Δt from when the circulation pump 17 is driven at the timing for detecting the cooling start temperature to when the circulation pump 17 is driven at the timing for detecting the comparison temperature. External temperature estimation detection data for estimating and detecting the external temperature surrounding the pair tube 31 based on the time Δt and the temperature deviation ΔT obtained by the deviation calculator 46 is stored.

The outside air temperature estimation detecting section 45 is provided with the deviation calculating section 4.
The outside air temperature surrounding the pair tube 31 is estimated and detected based on the temperature deviation ΔT obtained in step 6, the time Δt and the outside air temperature estimation detection data stored in the data storage unit 40.

More specifically, for example, data on the temperature change over time of the stagnant water in the pair tube 31 for each outside temperature as shown in FIG. When the detected temperature deviation ΔT is detected by 46, when the time Δt has elapsed after the detection of the cooling start temperature 40 ° C., the water temperature in the pair tube 31 is reduced by the temperature deviation ΔT from the cooling start temperature 40 ° C. Since the temperature has decreased, it is determined that the water temperature in the pair tube 31 indicates a temperature change indicated by a solid curve L2 in FIG.
2 is the temperature change data for the outside air temperature of −10 ° C., it can be determined that the outside air temperature around the pair tube 31 is −10 ° C.

[0093] Here, an example of the data of the temperature change over time of the water retained in the pair tube 31 when the cooling start temperature is 40 ° C is shown. In the case of, the data of the temperature change over time of the stagnant water of the pair tube 31 is also given.

The outside air temperature estimation / detection section 45 outputs the data of the outside air temperature estimated / detected as described above to the pump standby allowable time detection section 36.
Output to

When the estimated waiting outside temperature is received by the pump standby allowable time detecting section 36, the first embodiment is replaced with the estimated outside temperature based on the estimated outside temperature instead of the outside temperature detected by the outside temperature sensor 32. In the same manner as shown, the pump standby allowable time tz is detected, and the anti-freezing pump drive control unit 42 determines that the time elapsed since the forced drive of the circulating pump 17 by the temperature detection forced pump drive unit 48 is stopped is the pump standby allowable time. When the pump standby allowable time tz calculated by the time detection unit 36 is reached, the circulation pump 17 is driven to prevent freezing of the water in the reheating circulation passage 23, particularly, the pair tube 31.

According to this embodiment, the pair tube 3
Pair tube 3 based on the cooling temperature change of the stagnant water in 1
Since the configuration for estimating and detecting the outside air temperature around 1 is provided, the outside air temperature around the pair tube 31 can be estimated and detected almost accurately, and the pump standby allowable time tz is determined based on the estimated and detected outside air temperature. Since the detection is performed, the time until the temperature of the stay water in the pair tube 31 decreases to the temperature immediately before freezing can be accurately obtained as the pump standby allowable time tz. Can be reliably prevented.

In particular, as shown in FIG. 5, when the combustion equipment is installed indoors and the pair tube 31 is routed outside the room, the indoor air temperature change tendency and the outdoor air temperature change Since it is often different from the tendency and it is very difficult to detect a change in the outside air temperature around the pair tube 31 based on the detection value of the outside air temperature sensor 32, the accurate pump standby allowable time tz is detected. Although it is difficult, as shown in this embodiment, the pair tube 3
Pair tube 31 utilizing the cooling temperature change of the stagnant water 1
By providing a configuration for estimating and detecting the outside air temperature around, it is possible to detect an accurate pump standby allowable time tz as described above even with the installation form shown in FIG.
Freezing of the water in the pair tube 31 can be reliably avoided.

The present invention is not limited to the above embodiments, but may take various embodiments. For example, in each of the above embodiments, the pump standby permissible time detecting unit 36 detects the water temperature in the reheating circulation passage 23 from the bath temperature sensor 21 immediately before stopping the circulation pump 17. When the bath water is circulated in the reheating circulation passage 23 by the drive of the pump 17 and the water temperature is substantially uniform over the entire area of the reheating circulation passage 23, the bath temperature sensor 21 The detected water temperature may be taken in, for example, during the operation of the circulation pump 17 after the time when it is assumed that the water temperature in the entire area of the reheating circulation passage 23 becomes uniform after the driving of the circulation pump 17 is started. , Pump standby allowable time detecting unit 36
May take in the water temperature detected by the bath temperature sensor 21 or may take in the water temperature detected by the bath temperature sensor 21 immediately after the circulation pump 17 stops.

In each of the above embodiments, the first and second conditions as described above are given as the pump driving conditions. For example, in addition to the first and second conditions, A condition that the circulating pump 17 is driven at a predetermined time (for example, 5:00 am when the temperature is assumed to be the lowest) may be given, or the use of the bath may be monitored to determine whether the bath is used. The average daily use time of the bath is detected, and one based on the detected use time of the bath.
A condition that the circulating pump 17 is driven may be given when a predetermined time (for example, 5 hours) has elapsed from the time when bathing on the day is assumed to end. Also in such a case, when any one of the plurality of conditions given as the pump driving condition is satisfied, the circulation pump 17 is forcibly driven, and while the circulation pump 17 is being driven or immediately after the circulation pump 17 is stopped. The allowable pump standby time detector 36 detects the allowable pump standby time tz.

Further, in each of the above-described embodiments, the pump standby allowable time detecting section 36 determines the pump standby allowable time tz immediately before the stoppage of the freezing prevention pump drive. The pump standby allowable time tz may be determined during or immediately after the driving.

Furthermore, in each of the above embodiments, the allowable pump standby time tz 'for updating is the allowable pump standby time tz.
Is calculated by using the detected water temperature Th of the bath temperature sensor 21 used when calculating the timer 37. For example, the count of the timer 37 is reduced from the allowable pump standby time tz detected by the allowable pump standby time detector 36. In this case, the allowable pump standby time updating unit 35 fetches the detected water temperature of the bath temperature sensor 21 from time to time, and updates the allowable pump standby time tz ′ for updating based on the fetched water temperature of the bath temperature sensor 21. It may be detected. In such a case, for example, the count time of the timer 37 is compared with the allowable pump standby time tz ′ for updating, and it is determined that the allowable pump standby time tz ′ for update is shorter than the count time of the timer 37. In such a case, the count time of the timer 37 is changed to the pump standby allowable time tz 'for updating.

Further, in each of the above embodiments, the standby time detection data is given by the arithmetic expression data.
The water temperature Th detected by the bath temperature sensor 21 and the outside air temperature sensor 3
2 based on the detected outside air temperature Tg.
May be given as standby time detection data.

Further, in the second embodiment, the outside temperature estimation detection data is constituted by graph data, but the outside temperature estimation detection data may be constituted by tabular data. Temperature deviation detected by
The arithmetic expression data for estimating and detecting the outside air temperature around the pair tube 31 using the T and the time Δt from the detection of the cooling temperature to the detection of the comparison temperature as parameters may be given as the outside air temperature estimation detection data. .

Further, in each of the embodiments described above, a one-can-two-channel hot water supply / bath combination device has been described as an example. However, the present invention is provided with a reburning circulation passage with a circulation pump for circulating bath water. Anything can be applied,
For example, the present invention can be applied to a two-can-two-water-channel type hot water supply bath complex, a bath apparatus having no hot water supply function, and the like.

[0105]

According to the present invention, the time from when the circulation pump is stopped to when the circulation pump is driven before the water in the reheating circulation passage freezes is determined as the pump standby allowable time, and the time required to prevent freezing is determined. When the pump standby allowable time has elapsed since the circulation pump was stopped based on the pump stop condition, the circulation pump is driven.When the freeze prevention pump driving condition is satisfied, the circulation pump is driven. It is possible to prevent the water in the reheating circulation passage from freezing, and even if the driving condition for the anti-freezing pump is not satisfied, the above-mentioned condition is assumed after the circulation pump is stopped based on the stop condition for the anti-freezing pump. When the permissible pump standby time has elapsed, the water temperature in the external pipe portion where the freezing is most likely to occur in the reheating circulation passage has dropped to the temperature immediately before the freezing. In such a case, the circulation pump is driven, so that the bath tub water circulates in the reheating circulation passage, and ensures that freezing of water in the reheating circulation passage, especially in the external piping part, is ensured. Can be avoided.

While the circulating pump is stopped, the update pump standby allowable time is detected at predetermined timings. If the update pump standby allowable time is shorter than the previously detected pump standby allowable time, With a configuration that updates the allowable pump standby time to the allowable pump standby time for updating, or especially when detecting the allowable pump standby time for updating, it is detected during the previous operation of the circulating pump or immediately after it is stopped In a system equipped with a configuration for detecting the allowable pump standby time for updating based on the water temperature of the reheated circulation passage, the outside air temperature is lower than when the allowable pump standby time is detected, and the reheat circulation passage is detected. When the cooling rate of the water inside the pump increases, the allowable standby time of the pump can be changed according to the change in the cooling rate. It is possible to avoid freezing of water more reliably Reheating circulation passage.

In the apparatus provided with a structure for estimating and detecting the outside air temperature surrounding the combustion equipment, it becomes easy to estimate and detect the outside air temperature surrounding the external piping portion of the reheating circulation passage having the highest probability of freezing. The pump standby allowable time is detected based on the outside air temperature around the external pipe portion, and the anti-freezing operation is performed based on the pump standby allowable time, so that the external pipe portion can be more reliably prevented from freezing.

When the detected outside air temperature falls below the outside air temperature threshold value, or when the water temperature in the detected additional heating circulation passage falls below the circulation passage threshold value, the antifreeze pump driving condition is satisfied. Is determined, the detected outside air temperature is equal to the outside temperature threshold even if the water temperature in the detected reheating circulation passage is not lower than the circulation passage threshold value. When the temperature falls below the threshold value, the circulation pump is driven to prevent freezing, and even if the detected outside air temperature does not fall below the outside air temperature threshold value, the water temperature in the detected reheating circulation passage becomes the circulation passage threshold value. When the temperature falls below the threshold, the circulation pump is driven to prevent freezing.

On the other hand, for example, when the detected outside air temperature falls below the outside air temperature threshold value and the water temperature in the detected reheating recirculation passage falls below the circulation passage threshold value, the freezing prevention In the configuration in which the pump drive condition is determined to be satisfied and the pump is driven to prevent freezing, the detected outside air temperature and the detected circulation Since one of the water temperature of the passage is not lower than the threshold value, the circulation pump is not driven, and the problem that the water in the external piping portion freezes easily occurs. As described above, when at least one of the detected outside air temperature and the water temperature of the detected circulation passage is lower than the threshold value, the circulation pump is driven. Based on one side If the freezing of water can Reheating circulation passage is predicted, the circulating pump is driven. Moreover,
According to the present invention, as described above, since the circulation pump drive control for preventing freezing is performed based on the allowable pump standby time, the freezing of the water in the reheating circulation passage can be reliably avoided.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a characteristic control configuration in each of the embodiments.

FIG. 2 is a flowchart showing an embodiment of an antifreeze operation operation.

FIG. 3 is a flowchart illustrating an example of a drive control operation of a circulation pump in an antifreeze operation.

FIG. 4 is a graph showing an example of a temporal cooling temperature change of stay water in a pair tube.

FIG. 5 is an explanatory diagram showing an example of disposing a combustion device and a bathtub.

FIG. 6 is a model diagram showing an example of a combustion device.

[Explanation of symbols]

 3 Reheating Heat Exchanger 17 Circulation Pump 18 Bathtub 21 Bath Temperature Sensor 23 Reheating Heating Circulation Path 31 Pair Tube 32 External Temperature Sensor 35 Allowable Pump Standby Time Update Unit 36 Allowable Pump Standby Time Detector 40 Data Storage Unit 42 Freeze Prevention Pump Drive Control unit 43 Freeze prevention control unit 44 Temperature deviation detection unit 45 Outside air temperature estimation detection unit

Claims (5)

[Claims] 1. A reheating cycle circuit with a circulation pump for circulating bath water, a circulation path water temperature detecting means for detecting a water temperature in the reheating circuit, and an outside air temperature for detecting an outside temperature surrounding the combustion equipment. Detecting means for controlling the driving / stopping of the circulation pump based on predetermined freeze prevention pump drive conditions and pump stop conditions to prevent freezing of water in the reheating circulation passage. A combustion device, wherein the water temperature in the reheating circulation passage detected by the circulation passage water temperature detection unit during or immediately after the circulation pump is driven, and the outside air temperature detected by the outside air temperature detection unit, After the circulation pump is stopped, the reheating cycle is performed according to the data given in advance to calculate the allowable pump standby time by combining the water temperature in the reheating circulation passage and the outside air temperature. A pump standby permissible time detecting unit for obtaining a pump standby permissible time until the circulation pump is driven before water in the passage is frozen; and a detection of the pump standby permissible time after the circulation pump is stopped based on the pump stop condition. Antifreeze pump that drives the circulating pump to prevent freezing of water in the reheating circulation passage when the pump standby allowable time detected by the section has elapsed, even if the above-described freezing prevention pump driving condition is not satisfied. And a drive control unit. 2. A data storage unit for storing data of a pump standby permissible time; detecting a renewal pump standby permissible time at a predetermined timing while the circulating pump is stopped;
If the detected allowable pump standby time for updating is shorter than the allowable pump standby time stored in the data storage, the allowable pump standby time of the data storage is updated to the allowable pump standby time for updating. And an anti-freezing pump drive control unit that controls the drive of the circulation pump based on the allowable pump standby time stored in the data storage unit. The combustion device according to claim 1, wherein 3. A pump standby permissible time updating unit, based on the water temperature in the reheating circulation passage detected by the circulation passage water temperature detection means during or immediately after the previous operation of the circulation pump, updates the pump standby for updating. 3. The combustion apparatus according to claim 2, wherein an allowable time is detected and an operation of updating the pump standby allowable time is performed. 4. A circuit for circulating at a predetermined temperature detection timing interval while the circulation pump is stopped after the circulation pump water temperature is detected by the circulation passage water temperature detection means during or immediately after the operation of the circulation pump. The pump is forcibly driven to detect the water temperature in the reheating circulation passage by the circulation passage water temperature detecting means, and the deviation between the detected water temperature in the reheating circulation passage and the water temperature in the reheating circulation passage detected last time is detected. A temperature deviation detecting unit for detecting the temperature of water in the reheating circulation passage while the circulation pump is stopped; and a data for estimating and detecting an outside air temperature surrounding the combustion equipment based on a temporal temperature change of the water. Based on the water temperature deviation of the reheating circulation passage detected by the temperature deviation detection unit and the timing interval time of the temperature deviation detection unit, the outside air temperature surrounding the combustion equipment An outside air temperature estimation detection unit for performing estimation detection;
The pump standby allowable time detecting unit obtains the pump standby allowable time by using the outside air temperature estimated and detected by the outside air temperature estimation detecting unit instead of the detected outside air temperature by the outside air temperature detecting means. The combustion apparatus according to claim 1, wherein the combustion apparatus has a configuration. 5. When the outside air temperature detected by the outside air temperature detecting means is lower than the set outside air temperature threshold value, or when the water temperature of the reheating circulation passage detected by the circulation passage water temperature detecting means is set to the predetermined circulation. A freezing prevention control unit is provided for forcibly driving the circulating pump to prevent freezing of water in the reheating circulating passage when the temperature is lower than the passage water temperature threshold, assuming that the antifreezing pump driving condition is satisfied. The combustion device according to any one of claims 1 to 4, wherein: