JP2003130449A - Bath water heater - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bath water heater capable of changing its operation from heating operation directly to hot water supply action without spilling hot water into a bathtub. SOLUTION: During the heating operation, to switch from the heating operation to the action of supplying hot water into the bathtub in such a way that the temperature of water in a return path leading from a radiator 51 to a heat exchanger 22 is not higher than a predetermined temperature, a water passage is set so that the hot water from a hot water supply circuit flows out into the bathtub 5 through the return path.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat receiving pipe passing through a heat exchanger heated by a burner, a return pipe having one end connected to an inlet side of the heat receiving pipe and the other end opening to a bath, and the heat receiving pipe. A bath heating path consisting of a forward pipe having one end connected to the outlet side and the other end opening to a bath, a bypass pipe connecting the forward pipe and the return pipe, and the bath heating route through the bypass pipe. The bath heating path includes the switching means for switching between a closed state in which a closed circuit that bypasses the bathtub is formed and an open state in which the bathtub is opened, and a radiator disposed in the middle of the closed circuit. The present invention relates to a bath water heater capable of heating operation in which the heating is performed by the burner and the heat is dissipated by the radiator in a state where water is circulated in the closed circuit.

[0002]

2. Description of the Related Art Utility model registration gazette No. 2521199 as a bath water heater having a function of heating a bathroom is equipped with a three-way valve on each of the return pipe and the forward pipe of a bath heating path of the bath, and is replaced with a bathtub. Then, a configuration is disclosed in which the bath heating route is switched so that a closed circuit passing through a radiator in the warm air unit is formed.

In order to increase the heating capacity, the temperature of the hot water circulating in a closed circuit that does not pass through the bathtub is made higher. However, when switching from heating operation to pouring operation / heating operation, etc. Hot water in the circuit should not drain into the bathtub.
Therefore, in the heating system disclosed in Japanese Unexamined Patent Publication No. 2000-65370, when the bath heating route is switched from the closed circuit to the open circuit, the hot water temperature in the closed circuit is lowered and then the open circuit is entered. Has become. In this heating system, heat is dissipated from a radiator for heating to lower the hot water temperature, or hot water in a closed circuit is drained from a drain valve and replaced with room temperature water to lower the hot water temperature. .

[0004]

In the case where the hot water temperature in the closed circuit is lowered and then the operation is shifted to the open circuit operation, the combustion is stopped until the hot water temperature in the closed circuit drops, so that it is performed more than necessary. There is a problem that the outlet temperature of the heat exchanger for additional heating decreases, and the start-up is slow when switching to an open circuit and starting the additional heating operation. In particular, when adopting a so-called one-can two-water channel type in which a heat exchanger for additional heating and a heat exchanger for hot water supply are incorporated in a single can body, the hot water temperature in the closed circuit is lowered. Since the water temperature in the hot water supply pipe is lowered while the hot water is being supplied, there are problems such as an unpleasant change in the hot water temperature when the hot water is again discharged, and a slow start-up.

The present invention has been made by paying attention to the problems of the prior art as described above, and it is possible to immediately shift from heating operation to pouring operation without flowing hot water into the bathtub. The purpose is to provide a vessel.

[0006]

The gist of the present invention for achieving the above object resides in the inventions of the following items. [1] One end is connected to the heat receiving pipe (24) passing through the heat exchanger (22) heated by the burner (21) and the inlet side of the heat receiving pipe (24), and the other end is open to the bath (5). Return pipe (2
5) and a bath heating path (20) comprising one end connected to the outlet side of the heat receiving pipe (24) and the other end open to the bathtub (5), and the forward pipe (26) And a return pipe (25) for connecting the bypass pipe (41) and the bath heating path (20) to the bathtub (5) through the bypass pipe (41) to form a closed circuit. And switching means (A, for switching to an open state through the bathtub (5)
B, 100) and a radiator (51) arranged in the middle of the closed circuit, and the bath heating path (20) is set to the closed state and water is circulated in the closed circuit. In a bath water heater capable of heating operation in which heating by the burner (21) and heat dissipation by the radiator (51) are performed, the radiator (51) is connected to the forward pipe (26) or the forward pipe (26) of the closed circuit. The pouring means (28, 29, 100) for pouring water from the hot water supply circuit into the return pipe (25) and the pouring means (28, 29) while being arranged in the bypass pipe (41). , 100) through which water injected into the return pipe (25) passes through a part of the return path from the outlet side of the radiator (51) to the inlet side of the heat exchanger (22) in the closed circuit. Water flow path for pouring the return pipe into the bath (5) Pouring path switching means (A, B, 100) for switching is provided, the heating operation is performed so that the water temperature in the return path is below a predetermined temperature, and the pouring operation after the end of the heating operation is performed. A bath water heater characterized by switching the water passage to the return pipe pouring state.

[2] The pouring path switching means (A, B, 1)
00), the water injected into the return pipe (25) by the pouring means (28, 29, 100) flows through the return route and a forward route other than the return route in the closed circuit and the forward route. The water flow path at the time of pouring can be further switched to the forward / backward mixed pouring state in which the water flowing through the path and the water flowing through the return path merge and flow out to the bathtub (5). After the completion of the above, after the pouring operation is performed for a predetermined time in the return pipe pouring state, the bath is switched to the forward and backward mixed pouring state and the pouring operation is continued, [1] Water heater.

[3] The bath water heater according to [2], characterized in that the hot water supply temperature is set so that the water temperature after joining will be below a predetermined temperature.

[4] The return pipe pouring state is switched to the forward and backward mixed pouring state after the water from the hot water supply circuit reaches the confluence in the forward and backward mixed pouring state [2] ] Or [3] bath water heater.

[5] The time it takes for the water to make one round in the closed circuit is measured based on the water temperature fluctuation in the pipe after the heating operation is started, and the inside of the closed circuit is calculated from this and the pump flow rate during the heating operation. The capacity of the water passage from the location where the water from the hot water supply circuit is injected into the return pipe (25) to the confluent location is estimated based on this, and based on the estimated value,
The bath water heater according to any one of [2] to [4], wherein a timing at which the return pipe pouring state should be switched to the forward and backward mixing state is obtained.

[6] The pouring path switching means (A, B, 1)
00), the water from the hot water supply circuit is the bypass pipe (4
The water passage during pouring can be further switched to the normal pouring state in which the water flows into the bathtub (5) through both the return pipe (25) and the forward pipe (26) without passing through 1), The pouring operation in the backward mixed pouring state is performed for a predetermined time, and then the pouring operation is continued by switching to the normal pouring state. Bath water heater.

[7] The bath water heater according to [6], wherein after the water from the hot water supply circuit has spread to the outgoing route, the forward / backward mixed pouring state is switched to the normal pouring state. .

[8] The radiator (51) is arranged in the middle of the bypass pipe (41), and the radiator is connected to one connection part of the first three-way valve (B) inserted in the middle of the forward pipe (26). One end of the bypass pipe (41) is connected to one connection portion of the second three-way valve (A) inserted in the return pipe (25), and the bypass pipe (4)
1) is connected to the other end, and an air separator (44) is inserted into a bypass pipe (41) between the outlet side of the radiator (51) and the second three-way valve (A) to separate the air. The air bleeding pipe (46) of the device (44) is connected to the return pipe (25) on the bath (5) side of the second three-way valve (A) or the first three-way valve (B) is connected to the bath (5). ) Side is connected to the forward pipe (26), and a check valve (47) is attached in the middle of the air vent pipe (46) so that water does not flow backward to the air separator (44) through the pipe. The switching means (A, B, 100) and the pouring path switching means (A,
B, 100) switches the path by controlling the first three-way valve (B) and the second three-way valve (A). [1] to [7] Bath water heater.

The present invention operates as follows. In the heating operation, the water temperature of the return path from the radiator (51) to the heat exchanger (22) is kept below a predetermined temperature, and when switching from the heating operation to the pouring operation, the hot water from the hot water supply circuit returns to the return path. The water passage is set so as to flow out into the bathtub (5) through the portion of.

As described above, the heating operation is performed so that the water temperature in the return path, which is lower than the temperature in the outgoing path due to the heat radiation by the radiator (51), becomes equal to or lower than the predetermined temperature, and at the start of the pouring operation. Since the hot water is poured through the return path, the hot water is sent to the radiator (51) for efficient heating operation, and the hot water is not discharged to the bathtub (5), and the heating operation is changed to the pouring operation. You can switch immediately.

After the heating operation is completed, after the pouring operation through the return route is performed for a predetermined time, the water from the hot water supply circuit passes through both the return route and the forward route, and the water flowing through the forward route and the return route are passed. The water flow path is switched so that it merges with the flowing water and flows out to the bathtub (5), and the pouring operation is continued, and the hot water supply temperature is set so that the water temperature after merging at that time is below a predetermined temperature. However, the hot water remaining in the outgoing route at the end of the heating operation can be cooled to a temperature that is discharged into the bathtub (5). For example, after the water from the hot water supply circuit reaches the confluence, by switching from the pouring in the return route alone to the pouring in which the water from the outgoing route and the water from the return route are combined, The existing hot water and the water newly supplied from the hot water supply circuit can be mixed, and the temperature after mixing can be managed by controlling the hot water supply temperature.

The switching timing is determined as follows, for example. Measures the time it takes for the water to go around the closed circuit based on the water temperature fluctuations in the pipes after the heating operation is started.
From this and the pump flow rate during heating operation, the capacity of water in the closed circuit is obtained. Then, based on this, the capacity of the return path from the location where hot water from the hot water supply circuit is injected into the return pipe (25) to the confluence location is estimated (for example, assuming that the forward and return are equal to one half, Based on the estimated value, the timing at which the return pipe pouring state should be switched to the forward / backward mixing state is determined. As a result, the water passage can be switched at a timing according to the pipe length that differs depending on the installation state.

After the pouring operation in the mixed state is further performed for a predetermined time, the pouring operation is continued by switching to a state in which the water from the hot water supply circuit flows out to the bathtub (5) through the return path and the forward path. Since the molten metal is poured through the two paths of the return pipe (25) and the forward pipe (26), the pouring time is shortened. The timing of switching is that the water from the hot water supply circuit
After reaching the portion included in the closed circuit in 6), the hot water remaining in the outflow pipe (26) is cooled by mixing to completely discharge the hot water, and then the hot water is poured by two paths. Can be switched to.

For switching the water passage, for example, a radiator (51) is arranged in the middle of the bypass pipe (41) and one connection of the first three-way valve (B) inserted in the middle of the forward pipe (26). Part of the bypass pipe (41), and the other end of the bypass pipe (41) is connected to one connection part of the second three-way valve (A) inserted in the return pipe (25). The air separator (44) is inserted into the bypass pipe (41b) between the outlet side of 51) and the second three-way valve (A), and the air vent pipe (46) of the air separator (44) is connected to the second pipe (46). Connect to the return pipe (25) on the bath (5) side of the three-way valve (A) or the first three-way valve (B)
The check valve (47) is connected to the forward pipe (26) on the side closer to the bathtub (5) and prevents water from flowing backward to the air separator (44) through the pipe in the middle of the pipe (46) for air release. It is preferable to adopt a configuration in which the first three-way valve (B) and the second three-way valve (A) are controlled.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a schematic configuration of a bath water heater 10 according to an embodiment of the present invention. The bath water heater 10 includes a bath water heater body 10a, a bath warm switching unit 40, and a bath warm unit 50.

The bath water heater body 10a includes a burner 21 and
A heat exchanger 22 heated by the burner 21 and a combustion fan 23 for supplying and exhausting the burner 21 and the heat exchanger 22 are provided. The bath reheating path 20 for reheating the bath includes a heat receiving pipe 24 that passes through the heat exchanger 22 so as to bend back a plurality of times, and a return pipe 25 for returning the water in the bathtub 5 to the heat exchanger 22 side. , A forward pipe 26 for guiding the water heated in the heat exchanger 22 to the bath 5.

In the middle of the return pipe 25, a circulation pump 27 for flowing the water in the bath heating path 20 from the return pipe 25 to the outward pipe 26 via the heat receiving pipe 24 and the water temperature in the return pipe 25. A bath thermistor 45 for detecting is attached. A pouring pipe 28 for receiving hot water from the hot water supply circuit at the time of pouring the hot water into the bathtub 5 is connected to the return pipe 25. Pouring pipe 28
A pouring valve 29, which is normally closed and opened when pouring, is attached in the middle of. In addition, there is a bath water flow switch (not shown) in the middle of the return pipe 25. Further, a forward bath thermistor 31 for detecting the water temperature at the location is attached near the outlet side of the heat exchanger 22 in the forward pipe 26.

A return pipe 25 extended from the bath heating route 20
The forward pipe 26 communicates with the bathtub 5 via a bath warming switching unit 40 installed below the apron of the bathtub 5. Inside the bus warm switching unit 40, the return pipe 2
A three-way valve A is attached in the middle of 5, and a three-way valve B is attached in the middle of the forward pipe 26. The bypass pipe 41 is branched and extended from the portion of the three-way valve B, returns to the bus warming switching unit 40 via the radiator 51 in the bus warming unit 50, and is connected to the three-way valve A. The bypass pipe 41 includes a forward bypass pipe 41a from the three-way valve B to the radiator 51 and a return bypass pipe 41b from the exit side of the radiator 51 to the three-way valve A.

The connection port of the three-way valve A is connected to the return pipe 25 on the side leading to the bath 5, the connection port is connected to the return bypass pipe 41b, and the connection port is connected to the side of the return pipe 25 leading to the heat exchanger 22. . The connection port of the three-way valve B is connected to the forward pipe 26 on the side leading to the bath 5, the connection port is connected to the forward bypass pipe 41a, and the connection port is connected to the one of the forward pipes 26 leading to the outlet side of the heat exchanger 22. . By switching between the three-way valve A and the three-way valve B, the bath heating path 20 bypasses the bathtub 5 through the bypass pipe 41 and passes through the radiator 51 (FIG. 2).
The circuit is switched to a closed state in which the circuit shown by the thick line in () is formed or an open state in which an open circuit in which the bypass pipe 41 is separated via the bath 5 is formed.

Forward bypass pipe 41a and return bypass pipe 4
1b is connected inside the bus warm switching unit 40 by a shunt 42 so as to bypass the radiator 51.
A relay thermistor 4 for detecting the water temperature is provided between the three-way valve B and the diversion pipe 42 in the middle of the outgoing bypass pipe 41a.
3 is provided. In addition, in the middle of the return bypass pipe 41b and between the flow dividing pipe 42 and the three-way valve A, the air separator 4
4 is attached. The air bleeding pipe 46 of the air separator 44 is connected to the forward pipe 26 at the portion connecting the connection port of the three-way valve B and the bath 5, and the air bleeder pipe 46 is provided in the middle of the air bleeding pipe 46. A check valve 47 is attached to 44 so that water does not flow backward.

The bath warming unit 50 has a radiator 5 inside.
1 and a fan 52 for sending hot air to the bathroom by sending air to the radiator 51. Bath warming unit 50
Is usually installed near the ceiling of the bathroom. If the bath warming unit 50 is installed near the ceiling, the pressure loss becomes large, and even if water is circulated by the circulation pump 27 when the closed circuit is formed, it is not possible to secure a flow rate enough to turn on the bath water switch. Things can happen. For this reason, a diversion pipe 42 for bypassing the bath warming unit 50 is provided inside the bus warming switching unit 40 installed at a low place such as under the apron of the bathtub 5 so that the flow rate at the time of forming a closed circuit is earned. There is.

The control circuit 100 of the bath water heater 10 is built in the bath water heater main body 10a and stores a CPU (central processing unit) 101 which plays a central role in various controls and stores programs and various fixed data. ROM (read
(Only memory) 102 and a RAM for storing data and the like that are temporarily necessary for executing the program
(Random access memory) 103 and non-volatile R
The main part is the AM 104, and the CPU 101
The combustion fan 23, the blower 52, the three-way valve A, the three-way valve B, the circulation pump 27, the outflow bath thermistor 31, the relay thermistor 4 through the input / output interface circuit 105.
3. In addition to the pouring valve 29, a solenoid valve (not shown), a thermistor sensor, etc. are connected.

Further, a main remote controller installed in a kitchen or the like and a bath remote controller installed in a bathroom are also connected. The main remote controller and the bath remote controller have an operation unit including an operation switch and a heating on / off switch, and a display unit including a liquid crystal display.

Next, the operation will be described. When performing the heating operation, as shown in FIG. 2, the three-way valve A and the three-way valve B are switched to form a closed circuit (a pipe portion indicated by a thick line in the figure). That is, the three-way valve A is set in a state where the connection port and the connection port communicate with each other and the connection port is closed, and the three-way valve B is set in a state where the connection port and the connection port communicate with each other and the connection port is closed. In this state, heating is performed by the burner 21, water in the closed circuit is circulated by the circulation pump 27, the blower 52 is operated in the bath warming unit 50, and heat is radiated from the radiator 51 to heat the bathroom. During the heating operation, the water temperature in the return path from the radiator 51 to the heat exchanger 22 is measured by the bath thermistor 45, and the combustion amount of the burner 21 is controlled within the range where the temperature does not exceed a predetermined temperature. The predetermined temperature is set (for example, 60 ° C.) lower than the heat-resistant temperature (for example, 80 ° C.) of a bath made of artificial marble or plastic.

When switching from the heating operation to the pouring operation, as shown in FIG. 1, the circulation pump 27 is stopped, the three-way valve A is left as it is, and the three-way valve B is connected to the connection port, the connection port, and the connection port. Set to the state where all are closed (return pipe pouring state). Then, when the pouring valve 29 is opened and water or low-temperature hot water is injected from the hot water supply circuit to the return pipe 25 through the pouring pipe 28, the water flows out into the bathtub 5 through the route shown by the thick line in FIG. That is, the hot water injected from the pouring pipe 28 into the return pipe 25 does not flow toward the heat exchanger 22 because the three-way valve B is closed, and the return pipe 25, the three-way valve A and the air separator are separated. 44, an air bleeding pipe 46 in this order, enters the outward pipe 26 at a position closer to the bathtub 5 than the three-way valve B, and flows out to the bathtub 5. It should be noted that water may be passed through the return pipe, but in order to prevent unpleasant fluctuations in hot water temperature when tapping again, low-temperature hot water (36 to 45 ° C is preferable, for example 40
Degree) is preferred, and is hereinafter referred to as low temperature hot water.

This water passage includes only the return path portion from the radiator 51 to the heat exchanger 22 in the closed circuit shown in FIG. 2, and the forward path (from the heat exchanger 22 to the three sides) included in the closed circuit. It does not include the route from the valve B to the outlet side of the radiator 51). That is, at the end of the heating operation, the hot water (for example, 80 ° C.) does not go through the part of the outgoing path where hot water remains,
Only the part of the return path where the water temperature is controlled below a predetermined temperature during the heating operation passes. Therefore, even if the heating operation is immediately switched to the pouring operation, the pouring operation can be started without the hot water remaining in the outgoing path flowing out to the bathtub 5.

The pouring operation in the return pipe pouring state shown in FIG. 1 is continued for a predetermined time until the hot and cold water from the hot water supply circuit side reaches at least the air separator 44 as the confluence point. This time may be set in advance to a fixed time with a margin, or may be obtained by measurement / calculation corresponding to the installation situation, as will be described later. After performing the pouring operation in the return pipe pouring state for a predetermined time, the three-way valve B is set to the state in which the connection port communicates with the connection port and the connection port is closed, so that the water flow path is mixed back and forth. Switch to hot water state. As a result, the hot water from the hot water supply circuit flows through the water passage indicated by the thick line in FIG. That is, the pouring pipe 28
A part of the hot water flowing from the return pipe 25 from the same flows through the same route as shown by the thick line in FIG. 1, and the rest of the hot water flows through the heat exchanger 22, the three-way valve B and the radiator 51 or the diversion pipe. At the portion of the air separator 44 passing through 42, the hot and cold water flowing on the side of the three-way valve A is merged and mixed, and flows into the bath 5.

When switching to the backward and backward mixed pouring state, the hot water remaining in the forward path at the end of the heating operation (for example, 80 ° C.)
Are combined and mixed with hot water (for example, 40 ° C.) from the hot water supply circuit that has passed through the three-way valve A side in the air separator 44. By setting the temperature of hot water supplied from the hot water supply circuit to a low temperature, the temperature after mixing will be below a predetermined temperature (for example, 60
℃) is maintained.

The pouring operation in the forward / backward mixed pouring state is performed until the water temperature detected by the relay thermistor 43 falls below a predetermined reference temperature. Based on the temperature of the relay thermistor 43,
Confirm that the water in the path from the hot water supply circuit to the three-way valve B through the heat exchanger 22 has been replaced with hot water at the relatively low temperature supplied by the hot water supply circuit from the hot water at the end of the heating operation. There is.

After the confirmation is made, the three-way valve B is in communication with the connection port and the connection port is in a state in which the three-way valve A is in communication with the connection port and the connection port is closed. Switch to the closed state. As a result, the hot water supplied from the hot water supply circuit does not flow to the bypass pipe 41 side, but flows out into the bathtub 5 through both the return pipe 25 and the forward pipe 26. By switching to the pouring using the two routes in this way, the subsequent pouring time can be shortened.

Note that switching of the three-way valve at this time is not essential. For example, even if only the three-way valve A is switched and the three-way valve B is not switched, the control for pouring or reheating is performed after a predetermined time after the water temperature of the relay thermistor 43 drops below a predetermined reference temperature. Good. This is because the construction pipe length between the bath water heater main body 10a and the bath warming switching unit 40 differs at each construction site, while the bath warming switching unit 40 to the bath warming unit 50 has a high height in the bathroom, for example. This is because the predetermined time can be decided on the assumption that it is 5 m or less. Furthermore, when the control is switched to pouring or reheating after a predetermined time, it is not necessary to switch the three-way valves A and B either. Because the bath warm unit 5
This is because, if the blower 52 of 0 is stopped, the hot and cold water of the outgoing pipe 26 can reach the bathtub through the pipe 46 for bleeding air in both pouring and reheating.

FIGS. 4 to 7 show an example in which the air bleeding pipe 46 of the air separator 44 is connected at the confluent point 48 of the return pipe 25 on the bath 5 side of the three-way valve A.
FIG. 4 shows a state in which a closed circuit is configured to perform heating operation. At this time, the combustion control is performed so that the temperature detected by the bath thermistor 45 becomes equal to or lower than a predetermined temperature. The filled pipe portion in the figure shows a portion where hot water is present, and the pipe portion shaded in two directions shows a portion where hot water below a predetermined temperature exists. In FIG. 5, the return pipe pouring state is set, hot water from the hot water supply circuit is caused to flow through the return path in the closed circuit, and the hot water in the return path portion is replaced with hot water from the hot water supply circuit to perform the pouring operation. ing. The temperature from the hot water supply circuit at this time is set so that the water temperature after mixing will be equal to or lower than a predetermined temperature in the next backward and backward mixed pouring state. In the figure, a pipe portion shaded in one direction is a portion where hot water is supplied from the hot water supply circuit and indicates a relatively low temperature portion.

After the pouring operation in the state of FIG. 5 is continued for a certain period of time, pouring is performed in the forward / backward mixed pouring state of FIG. That is,
The water that has passed through the return path portion of the closed circuit and the water from the outgoing path side are merged at the merge point 48 to be mixed, and then flown out to the bath 5. After the temperature detected by the relay thermistor 43 reaches a temperature corresponding to the hot water supply temperature, the water passage is further switched, and the pouring operation is performed through the two paths of the return pipe 25 and the forward pipe 26 as shown in FIG. It has become.

Next, a case will be described in which the switching timing from the return pipe pouring state to the forward and backward mixing pouring state is obtained and set after the installation of the equipment. The timing of switching the three-way valve B in order to change the return pipe pouring state to the backward mixed pouring state is the amount of hot water in the pipe during the heating operation (closed circuit water amount).
Then, based on this, estimate the amount of hot water (return pipe purge water amount) in the return pipe at the time of pouring (the pipe line through which pouring / water is started and the hot water reaches the bathtub) . Then, when pouring water, the flow rate is counted by a flow sensor (not shown) in the water supply pipe of the water heater, and the amount estimated in advance (return pipe purge water amount)
When 3 is counted, the three-way valve B is switched to switch to the forward / backward mixed pouring state.

For the amount of hot water in the pipe during heating operation (closed circuit water amount), (a) the pump flow rate is obtained, and (b) the hot water in the pipe (closed circuit) during heating makes one round. Seek from time. For example, when the pump flow rate is 6.7 liters / minute and the time for one rotation is 2 minutes, the amount of hot water in the closed circuit is considered to be 13.4 liters. The measurement of the amount of hot water in the pipe may be measured and stored during the first heating operation after installation of the appliance, or may be updated every heating operation.

(A) The pump flow rate is obtained from the combustion amount and the temperatures detected by the bath thermistor 45 and the relay thermistor 43. For example, when the heating operation is performed and the combustion amount after a predetermined time is OU
When TPUT 33600 KJ / h, the temperature of the bath thermistor 45 is 60 ° C., and the temperature of the relay thermistor 43 is 80 ° C., the flow rate L = (33600 ÷ 4.2 ÷ 60) ÷ (80-60) =
It can be calculated at 6.7 l / min.

(B) To obtain the time required for the hot water in the pipe to make one revolution during heating, the time measurement is started at the same time as the start of combustion. At the same time, it is determined whether to use the measurement data. The reliability of the measurement data is higher when the hot water in the pipe is cold after a predetermined time (for example, several hours) from the previous heating (or heating). (A timer may measure the time since the last heating). Therefore, it is desirable to confirm in advance that the bath thermistor 45 and the relay thermistor 43 are at a temperature close to the outside air temperature (for example, 30 ° C. or lower), and judge whether or not the measured data can be used (when attaching for preventing freezing). There may be an outside temperature thermistor data).

Then, when the bath thermistor 45, which has been outputting a temperature close to the outside air temperature until now, detects a temperature increase (for example, an increase of 10 ° C. or more) as a heating return, the clock is stopped, so that the heating pipe ( Find the time for the hot water in the closed circuit to go around the pipe once.

If there is a temperature difference between the bath thermistor 45 and the relay thermistor 43 (for example, 10 ° C. or higher) at the time of starting the clock measurement, the temperature of the water in the equipment or the pipe near the equipment is rising due to the sun or the like. Since it is expected that the bath thermistor 45 will detect a temperature rise earlier than the hot water in the heating pipe makes one round around the pipe, the temperature difference may be used as a material for determining whether or not the data to be measured can be used. FIG. 8 shows a flow of the above-mentioned processing.

Return pipe at the time of pouring (pouring / pouring is started,
Estimate the amount of hot water (return pipe purged water amount) in the pipe passage through which the hot water reaches the bathtub. At this time, the condition that the return pipe becomes long when pouring is a) when the pouring pipe of the equipment is connected to the outflow pipe of the bath. I) When the cistern tank in the three-way valve unit (bus warm relay unit) is also poured and replaced. When there is a circulation adapter on the opposite side of the three-way valve unit (usually installed under the bathtub apron under the bath warm). This is a case where the above three conditions overlap.

The amount of hot water obtained in the above (a) and (b) is
The amount of hot water in the following pipeline. (C) Piping between bath water heater and 3-way valve unit (d) Piping between 3-way valve unit and radiator (e) Heat exchanger inside radiator (f) Piping between radiator and 3-way valve unit (g) Inside 3-way valve unit Piping between the three-way valve unit from the cistern tank (h) to the bath water heater (i) Heat exchanger inside the bath water heater. Of these, approximately (c) =
(H), (d) = (f), and (e) = (i).

Of these, the piping becomes long when pouring.
The piping for the condition of (i) is a heat exchanger in the bath water heater + (c) piping between the bath water heater and the three-way valve unit + (g) a system turn tank inside the three-way valve unit + (j) piping between the three-way valve unit and the bathtub Yes, (j) is a large Japanese-Western eclectic bathtub.
Since it is about 5 m to 2 m, it is considered that the pipe length is almost the same as (d).

Therefore, the amount of hot water obtained from (a) and (b) = 2 ((c) + (d) + (e)) + (g),
A) ~ U) amount of hot water in piping = (c) + (d) + (e)
It becomes + (g). Since (g) is a tank of 1 liter, for example, the amount of hot water in the pipe during heating is 1
When considering 3.4 liters, the amount of hot water in the return pipe when pouring (return pipe purge water amount) can be estimated to be about 7.2 liters.

As another method, the condition that the return pipe at the time of pouring becomes short will be estimated. The condition at that time is, for example, when the pouring pipe of the appliance is connected to the return pipe of the bath. O) When the cistern tank in the three-way valve unit (bus warm relay unit) is not replaced when pouring. However, all of them are design matters that can be known in advance. Also, (e), (i),
The items shown in each item of (g) are also design matters to be known in advance.
Therefore, for example, the amount of hot water obtained earlier is 13.4 liters,
(E) + (i) + (g) = 2 ((c) at 3 liters)
It is estimated that + (d)) = 10.4 liters.

For the piping under the conditions of this time, e) and o), it is sufficient to obtain (c) + (j). Therefore, considering (j), the shortest of (j) is next to the circulation adapter. There is a three-way valve unit, and the longest case is when there is a circulation adapter on the opposite side across the bathtub.
It is considered that (d) ≧ (j). Therefore, 2 ((c) +
When (d)) = 10.4 liters, the amount of hot water in the return pipe at the time of pouring can be estimated to be 5.2 liters or less, if possible.

Although the present application describes a method in which hot water in the closed circuit does not flow out to the bathtub when the heating operation is switched to the pouring operation, when the heating operation is switched to the reheating operation, the closed circuit is also once. If the hot water inside is discharged into the bathtub in a non-hot state and then switched to the heating operation, it is possible to switch from the heating operation to the heating operation without the hot water flowing into the bathtub.

[0052]

According to the bath water heater of the present invention, the heating operation is performed so that the water temperature in the return path from the radiator is below a predetermined temperature, and when the heating operation is switched to the pouring operation, the return operation is performed. Since it was configured to pour through the route,
It is possible to immediately switch from heating operation to pouring operation without discharging hot water into the bathtub.

After the heating operation is completed, the pouring operation through the return path is performed for a predetermined time, and then the water from the hot water supply circuit passes through both the return path and the outward path from the heat exchanger to the radiator. The water flow path is switched so that the flowing water and the water flowing through the return path merge and flow out to the bathtub, and the pouring operation is continued, and at this time, the water temperature after merging falls below a predetermined temperature. When the hot water supply temperature is set, it is possible to lower the temperature of hot water in the outgoing route during the heating operation and discharge the hot water into the bathtub.

Further, after the pouring operation in the merged state is carried out for a predetermined time, when the pouring operation is continued by switching to a state in which the water from the hot water supply circuit flows out to the bathtub through the return path and the forward path, Since the pouring is done through two routes,
The pouring time is shortened. By switching the timing after the water from the hot water supply circuit reaches the part of the outflow pipe that is included in the closed circuit, the hot water in the outflow pipe is completely discharged with the temperature lowered by merging. It is possible to switch to pouring by two routes.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a schematic configuration of a bath water heater according to an embodiment of the present invention and a pouring path in a return pipe pouring state immediately after switching from a heating operation to a pouring operation.

FIG. 2 is an explanatory diagram showing a schematic configuration of a bath water heater according to an embodiment of the present invention and a circulation path (closed circuit) during heating operation.

FIG. 3 is an explanatory view showing a schematic configuration of a bath water heater according to an embodiment of the present invention and a pouring path in a backward mixed pouring state.

FIG. 4 is an explanatory diagram showing a schematic configuration of a bath water heater having another piping configuration and a circulation path (closed circuit) during heating operation.

FIG. 5 is an explanatory diagram showing a schematic configuration of a bath water heater having another piping configuration and a pouring path in a return pipe pouring state immediately after switching from heating operation to pouring operation.

FIG. 6 is an explanatory view showing a schematic configuration of a bath water heater having another piping configuration and a pouring path in a backward mixed pouring state.

FIG. 7 is an explanatory diagram showing a schematic configuration of a bath water heater having another piping configuration and a pouring path in a normal pouring state.

FIG. 8 is a flow chart showing a process of obtaining a switching timing from the return pipe pouring state to the forward and backward mixing pouring state.

[Explanation of symbols] ~…Connection A ... 3-way valve B ... Three-way valve 5 ... Bathtub 10 ... Bath water heater 10a ... Bath water heater body 20 ... Bath heating route 21 ... Burner 22 ... Heat exchanger 23 ... Combustion fan 24 ... Heat receiving tube 25 ... Return pipe 26 ... Outgoing 27 ... Circulation pump 28 ... Pouring pipe 29 ... Pouring valve 31… Outdoor bath thermistor 40 ... Bus warm switching unit 41 ... Bypass pipe 41a ... Outgoing bypass pipe 41b ... Return bypass pipe 42 ... Dividing pipe 43 ... Relay thermistor 44 ... Air separator 45 ... Bath thermistor 46 ... Piping for venting air 47 ... Check valve 48 ... Confluence 50 ... Bath warming unit 51 ... Radiator 52 ... Blower

Claims (8)

[Claims] 1. A heat receiving pipe passing through a heat exchanger heated by a burner, one end of which is connected to an inlet side of the heat receiving pipe and the other end of which is connected to an outlet side of the heat receiving pipe and one end of which is connected to an outlet side of the heat receiving pipe. A bath heating path having a forward pipe with the other end open to the bath, a bypass pipe connecting the forward pipe and the return pipe, and a bath heating route for closing the bath bypassing the bath pipe through the bypass pipe. A switching unit that switches between a closed state in which a circuit is formed and an open state through the bath, and a radiator disposed in the middle of the closed circuit, and sets the bath heating path to the closed state In a bath water heater capable of heating operation in which heating is performed by the burner and heat is dissipated by the radiator while water is circulated in the closed circuit, the radiator is the forward pipe or the bypass pipe in the closed circuit. The water from the hot water supply circuit For injecting water into the return pipe and water injected into the return pipe by the pouring means between the outlet side of the radiator and the inlet side of the heat exchanger in the closed circuit. And a pouring route switching means for switching the water passage during pouring to a return pipe pouring state that flows out to the bathtub through a part of the return route, so that the water temperature in the return route falls below a predetermined temperature. The bath water heater, wherein the heating operation is performed, and the pouring operation after the heating operation is finished is performed by switching the water passage to the return pipe pouring state. 2. The pouring path switching means is such that the water injected into the return pipe by the pouring means flows through the return path and a forward path other than the return path in the closed circuit, and the forward path. It is possible to further switch the water flow path during pouring to the forward and backward mixed pouring state in which the water that has flowed through and the water that has flowed through the return path merge and flow out into the bathtub, and after the heating operation ends, The bath water heater according to claim 1, wherein after the pouring operation is performed for a predetermined time in the return pipe pouring state, the pouring operation is continued by switching to the forward and backward mixed pouring state. 3. The bath water heater according to claim 2, wherein the hot water supply temperature is set so that the water temperature after joining will be equal to or lower than a predetermined temperature. 4. The return pipe pouring state is switched to the forward-back mixing pouring state after the water from the hot-water supply circuit reaches the confluence in the forward-back mixing pouring state. Or the bath water heater described in 3. 5. The time taken for the water to make one round in the closed circuit is measured based on the water temperature fluctuation in the pipe after the heating operation is started, and the time taken for the water to flow in the closed circuit is measured from this and the pump flow rate during the heating operation. Obtain the capacity, and based on this, estimate the capacity of the water passage from the point where the water from the hot water supply circuit is injected into the return pipe to the confluence point, and based on the estimated value, return pipe pouring The bath water heater according to any one of claims 2 to 4, wherein the timing for switching from the state to the forward / backward mixed state is obtained. 6. The pouring route switching means, when pouring water to a normal pouring state in which water from the hot water supply circuit flows into the bathtub through both the return pipe and the forward pipe without passing through the bypass pipe. The water passage can be further switched, and after performing the pouring operation in the forward and backward mixed pouring state for a predetermined time, it is switched to the normal pouring state and the pouring operation is continued. The bath water heater according to any one of claims 2 to 5. 7. The bath water heater according to claim 6, wherein after the water from the hot water supply circuit has spread to the outgoing route, the forward / backward mixed pouring state is switched to the normal pouring state. 8. The radiator is arranged in the middle of the bypass pipe, and one end of the bypass pipe is inserted in the middle of the return pipe at one connection portion of the first three-way valve inserted in the forward pipe. The other end of the bypass pipe is connected to one connection part of the second three-way valve, and an air separator is inserted into the bypass pipe between the outlet side of the radiator and the second three-way valve to separate the air. Connecting the air vent pipe of the container to the return pipe on the bath side of the second three-way valve or on the bath line of the first three-way valve on the bath side.
A check valve is attached in the middle of the air vent pipe so that water does not flow backward to the air separator through the pipe, and the switching means and the pouring path switching means are the first
The bath water heater according to any one of claims 1 to 7, wherein the path is switched by controlling the three-way valve and the second three-way valve.