Hot water heating apparatus

Abstract

To provide a hot water heating apparatus that prevents clogging in a bypass thermal valve.SOLUTION: A process to be executed by a controller of a hot water heating apparatus includes: a step (S520) of starting the combustion operation of a hot water supply system; a step (S530) of detecting the temperature of a heated heat medium based on output from a temperature sensor; a step (S540) of determining whether the temperature increase level corresponds to the temperature increase level in the case of a bypass thermal valve being clogged; and a step (S580) of executing a clog removal operation for the bypass thermal valve, if the bypass thermal valve has been determined to be clogged (YES in step S540).SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present disclosure relates to control of a hot water heating system, and more particularly to removal of foreign matter in a hot water heating system. [Background technology]

[0002] 2. Description of the Related Art Conventionally, there are known techniques for easily removing clogging in the circulation path or bypass circuit of a hot water heating system, that is, for easily removing causative substances (see, for example, Patent Documents 1 to 4). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2010-139175 A [Patent Document 2] JP 2005-49078 A [Patent Document 3] JP 2004-144445 A [Patent Document 4] JP 2005-30707 A Summary of the Invention [Problem to be solved by the invention]

[0004] The thermal valve provided in the bypass circuit may have a groove in the valve body. When the low-temperature terminal connected to the hot water heating device is operated, the thermal valve opens and the heat medium circulates, but when the high-temperature terminal is operated, the thermal valve does not open and the heat medium passes through the groove in the valve body and circulates. However, if the low-temperature terminal is not connected to the hot water heating device or has not been used for a long period of time, and the thermal valve does not open, the groove may become clogged. In this case, when the high-temperature terminal is operated, if the thermal valve of the high-temperature terminal is not open, the heating water may not circulate at the stage of warming the heating water at the start of heating operation. Furthermore, if combustion is performed without circulating the heating water, a boiling sound will be generated from the can body, and the can body may be damaged. Therefore, a technology is needed to improve the clogging of the groove of the thermal valve.

[0005] The present disclosure has been made in view of the above-described background, and one object according to a certain aspect is to provide a technique for suppressing clogging of a thermal valve. [Means for solving the problem]

[0006] According to an embodiment, a hot water heating device is provided. The hot water heating device includes a combustion unit, a heat exchanger, a circulation path including a high-temperature terminal path and a low-temperature terminal path for circulating a heat medium, a bypass path for connecting the high-temperature terminal path and the low-temperature terminal path, a pump arranged in the circulation path, a first thermal valve provided in the bypass path, a temperature sensor for detecting the temperature of the heat medium, and a control device for controlling the hot water heating device. A groove for flowing the heat medium is provided in the valve body or valve seat of the first thermal valve. The control device detects clogging in the groove based on a rate of change in the temperature of the heat medium when starting a heating operation in which the heat medium circulates, and based on the detection of the clogging, changes the first thermal valve to an open state and operates the pump as a foreign object removal operation after the heating operation.

[0007] In one aspect, the temperature sensor is disposed in the hot terminal path, and detecting a clog in the groove based on a rate of change of temperature includes detecting the occurrence of a clog in the groove based on the heat transfer medium increasing in temperature in a time that is faster than a predetermined time.

[0008] In one aspect, the hot water heating apparatus further includes a notification unit that issues a notification regarding replacement of the heat medium based on the fact that the foreign matter removal operation has been performed a preset number of times or more during a predetermined first period.

[0009] In one aspect, the hot water heating apparatus further includes a notification unit that issues a notification regarding inspection of the circulation path based on the fact that the foreign object removal operation has been performed a preset number of times or more during a predetermined first period.

[0010] In one aspect, the hot water heating device further includes a storage unit that stores the number of times that the foreign object removal operation has been performed. The control device erases the number of times that the foreign object removal operation has been performed when the foreign object removal operation has not been performed a predetermined number of times during a first period.

[0011] In one aspect, a second thermal valve is disposed in the high-temperature terminal path. When starting a heating operation, the control device detects the temperature of the heat medium based on an output from the temperature sensor when the second thermal valve is closed.

[0012] In one aspect, the control device performs the foreign matter removal operation based on the fact that the foreign matter removal operation has not been performed during a predetermined second period of time.

[0013] According to an embodiment, clogging of the first thermal valve provided in the bypass path can be suppressed.

[0014] The above and other objects, features, aspects and advantages of the present invention will become apparent from the following detailed description of the invention taken in conjunction with the accompanying drawings. [Brief description of the drawings]

[0015] [Figure 1] 1 is a diagram showing an outline of the configuration of a hot water supply system 100. FIG. [Diagram 2] FIG. 2 is a block diagram illustrating the connection relationship between a heating circuit 103 and a heating device. [Diagram 3] 2 is a block diagram showing a schematic control structure of a controller 300 included in the hot water supply system 100. FIG. [Figure 4] 4 is a flowchart showing a part of a process executed by a controller 300 to realize a foreign object removal operation. [Diagram 5] 4 is a flowchart showing a part of the process executed by controller 300 when a heating operation is instructed. [Figure 6] 13 is a diagram showing an example of a message displayed on the monitor 630 of the controller 300. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the following description, the same components are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated.

[0017] The configuration of the hot water supply system 100 will be described with reference to FIG. 1. FIG. 1 is a diagram showing an outline of the configuration of the hot water supply system 100. The hot water supply system 100 includes a hot water supply circuit 101, a reheating circuit 102, a heating circuit 103, and a controller 300. The hot water supply circuit 101 is configured to supply hot water when a hot water tap such as a faucet 105 or a shower (not shown) is opened. The reheating circuit 102 is configured to heat and circulate hot water in a bathtub (not shown). The heating circuit 103 is configured to circulate and supply hot water, which is a liquid heat medium, to a heating device exemplified in FIG. 2. The controller 300 is configured, for example, by a microcomputer. The controller 300 may be incorporated in the housing of the hot water supply system 100, or may be provided as a remote controller in a kitchen or other living area.

[0018] The reheating circuit 102 is configured to form a reheating circulation path for heating and circulating the hot water in the bathtub between the bathtub water inlet 191 and the bathtub water outlet 192. The bathtub water inlet 191 and the bathtub water outlet 192 are each connected via piping to an opening provided in a bathtub adapter (not shown) placed in the bathtub. A heating device that receives a heat medium from the heating circuit 103 is connected between the heating return port 302 and the heating output port (low temperature) 304, or between the heating return port 302 and the heating output port (high temperature) 306.

[0019] The hot water supply circuit 101 includes a primary heat exchanger 11a, a secondary heat exchanger 21a, and a combustion burner 30a, which are housed in the boiler body 10. The hot water supply circuit 101 further includes a water inlet pipe 50, a bypass pipe 60, and a hot water outlet pipe .

[0020] Tap water or the like is supplied to the water inlet pipe 50. A bypass pipe 60 is arranged between the water inlet pipe 50 and the hot water outlet pipe 70. A distribution valve 80 is interposed and connected to the water inlet pipe 50 to control the diversion to the bypass pipe 60. A portion of the water supply is diverted from the water inlet pipe 50 to the bypass pipe 60 depending on the opening degree of the distribution valve 80. Furthermore, a temperature sensor 110 and a flow rate sensor 150 are arranged in the water inlet pipe 50. The temperature sensor 110 detects the inlet water temperature. The flow rate sensor 150 is arranged downstream of the distribution valve 80 (on the boiler body side) and detects the flow rate passing through the boiler body 10 (boiler body flow rate).

[0021] The water in the water inlet pipe 50 is first preheated by the secondary heat exchanger 21a, and then is mainly heated in the primary heat exchanger 11a. The hot water heated to a preset temperature by the primary heat exchanger 11a and the secondary heat exchanger 21a is discharged from the hot water outlet pipe 70.

[0022] The hot water outlet pipe 70 is connected to the bypass pipe 60 at a junction 75. Therefore, the hot water supply system 100 supplies hot water at an appropriate temperature, which is a mixture of high-temperature water output from the boiler body 10 and low-temperature water from the bypass pipe 60, to a predetermined hot water supply point such as a hot water tap in a kitchen or bathroom, or a hot water supply circuit to a bathtub.

[0023] The hot water outlet pipe 70 is provided with a flow rate adjustment valve 90 and temperature sensors 120, 130. The temperature sensor 120 is disposed upstream (towards the boiler body) of the junction 75 where the hot water outlet pipe 70 meets the bypass pipe 60, and detects the hot water temperature output from the boiler body 10. The temperature sensor 130 is disposed downstream (on the hot water outlet side) of the junction 75, and detects the hot water outlet temperature Th after the water from the bypass pipe 60 is mixed. The flow rate adjustment valve 90 is provided to control the hot water outlet flow rate. The temperature sensors 110, 120, 130 are, for example, constituted by thermistors.

[0024] In the can body 10, a mixture of fuel gas and combustion air supplied by a blower fan 40 is output from the combustion burner 30a. The mixture is ignited by an ignition device (not shown), causing the fuel gas to burn and generating a flame. Combustion heat generated by the flame from the combustion burner 30a is provided to the primary heat exchanger 11a and the secondary heat exchanger 21a in the can body 10.

[0025] The primary heat exchanger 11a heats the inlet water by heat exchange using sensible heat (combustion heat) of the combustion gas from the combustion burner 30a. The secondary heat exchanger 21a heats the water flowing through it by using latent heat of the combustion exhaust gas from the combustion burner 30a. An exhaust path 15 for discharging the combustion exhaust gas after heat exchange is provided downstream of the combustion gas flow direction of the can body 10. In this way, in the can body 10, the primary heat exchanger 11a and the secondary heat exchanger 21a heat the water supplied from the water inlet pipe 50 by the amount of heat generated by combustion in the combustion burner 30a.

[0026] A main gas solenoid valve 32, a gas proportional valve 33, and capacity switching valves 35a to 35c are arranged in a gas supply pipe 31 to the combustion burner 30a. The main gas solenoid valve 32 has a function of turning on and off the supply of fuel gas to the combustion burner 30a. The gas flow rate in the gas supply pipe 31 is controlled according to the opening degree of the gas proportional valve 33. The capacity switching valves 35a to 35c are controlled to open and close in order to switch the number of burners (number of burner combustions) to which fuel gas is supplied among the multiple combustion burners 30a.

[0027] Next, a description will be given of the configuration related to hot water supply to the bathtub in hot water supply system 100. In the following, hot water supply to the bathtub will be referred to as "pouring hot water," and hot water supply to hot water taps other than the bathtub (such as faucet 105) will be simply referred to as "hot water supply."

[0028] The hot water supply system 100 further comprises a hot water supply pipe 180 that branches off from the hot water outlet pipe 70 to supply hot water to a bathtub (not shown). The hot water supply pipe 180 branches off from the hot water outlet pipe 70 via a flow rate adjustment valve 90. Furthermore, a hot water supply solenoid valve 210 and a check valve 220 are interposed and connected to the hot water supply pipe 180. The hot water supply pipe 180 is connected at a junction 185 to the bath return piping 190, which will be described later.

[0029] By controlling the opening and closing of the hot water supply solenoid valve 210 by the controller 300, it is possible to control the formation / cut-off of a path for pouring hot water from the hot water supply circuit 101 to the bathtub.

[0030] The reheating circuit 102 includes a bath return pipe 190, a bath supply pipe 195, a reheating circulation pump 400, and a bath heat exchanger 410.

[0031] The bath return pipe 190 is provided between the bath water intake port 191 and the intake port of the reheating circulation pump 400. The discharge side of the reheating circulation pump 400 is connected to one end of the bath heat exchanger 410. The other end of the bath heat exchanger 410 is connected to the bath water outlet port 192 by the bath supply pipe 195.

[0032] During reheating operation, the reheating circulation pump 400 operates to draw hot water from the bathtub into the hot water supply system 100 through the bathtub water intake port 191. A reheating circulation path is then formed in which the drawn hot water passes through the bath return pipe 190, the reheating circulation pump 400, the bath heat exchanger 410, and the bath supply pipe 195, and is returned to the bathtub through the bathtub water outlet port 192. In the reheating circulation path, temperature sensors 374 and 372 are provided on the input and output sides of the bath heat exchanger 410, respectively.

[0033] During reheating operation, the thermal valve 330 of the heating circuit 103 is opened. This causes the heat medium heated in the heating circuit 103 (described later) to flow through the bath heat exchanger 410. As a result, the hot water in the reheating circulation path is heated by the bath heat exchanger 410, and the temperature of the hot water in the bathtub can be increased.

[0034] Furthermore, the bath return pipe 190 is connected to the hot water supply pipe 180 at the junction 185. As a result, when the hot water supply solenoid valve 210 is opened, hot water from the hot water supply circuit 101 is supplied to the junction 185 via the hot water supply pipe 180. Because the reheating circulation pump 400 is stopped during the hot water supply operation, the supplied hot water is supplied into the bathtub from both the bathtub water inlet 191 and the bathtub water outlet 192 via the bath return pipe 190 and the bath supply pipe 195, respectively.

[0035] [Heating circuit] Next, the heating circuit 103 in the hot water supply system 100 will be described with reference to Fig. 2. Fig. 2 is a block diagram illustrating the connection relationship between the heating circuit 103 and a heating device.

[0036] During heating operation, the heating circuit 103 is configured to form a circulation path for a heat medium (typically, hot water) between the heating return port 302 and the heating output port (low temperature) 304, and between the heating return port 302 and the heating output port (high temperature) 306.

[0037] A high temperature heating terminal 500 is connected between the heating return port 302 and the heating output port (high temperature) 306. The high temperature heating terminal 500 has a high temperature heating device 510 and a thermal valve 520. The opening and closing of the thermal valve 520 is controlled by a controller (not shown) of the high temperature heating terminal 500.

[0038] The thermal valve 520 is opened when the high-temperature heating device 510 is operating and during freeze prevention operation described below. When the thermal valve 520 is opened, a heat medium circulation supply path is formed between the high-temperature heating device 510 and the heating circuit 103, via the heating return port 302 and the heating output port (high temperature) 306. For example, the high-temperature heating device 510 is configured by a room heater that outputs hot air heated by the heat medium from the heating circuit 103.

[0039] A plurality of low-temperature heating terminals 600 are connected between the heating return port 302 and the plurality of heating output ports (low temperature) 304. Each of the plurality of heating output ports (low temperature) 304 is provided with a terminal thermal valve 305 that is controlled to open and close in response to a command from the controller 300.

[0040] Each low-temperature heating terminal 600 has a low-temperature heating device 610. When the terminal thermal valve 305 is opened, a heat medium circulation supply path is formed between the corresponding low-temperature heating device 610 and the heating circuit 103 via the heating return port 302 and the heating output port (low temperature) 304. For example, the low-temperature heating device 610 is composed of a hot water panel for floor heating, through which the heat medium from the heating circuit 103 flows.

[0041] 1 again, the heating circuit 103 includes a primary heat exchanger 11b, a secondary heat exchanger 21b, and a combustion burner 30b. The primary heat exchanger 11b, the secondary heat exchanger 21b, and the combustion burner 30b are housed in the boiler body 10 common to the primary heat exchanger 11a, the secondary heat exchanger 21a, and the combustion burner 30a of the hot water supply circuit.

[0042] The primary heat exchanger 11b heats the incoming water by heat exchange using the sensible heat (combustion heat) of the combustion gas from the combustion burner 30b. The secondary heat exchanger 21b heats the flowing water by heat exchange using the latent heat of the combustion exhaust gas from the combustion burner 30b. The number of burners (number of burners) to which fuel gas is supplied among the multiple combustion burners 30b is switched by controlling the opening and closing of the capacity switching valves 36a and 36b. Fuel gas is supplied to the combustion burner 30b via the gas supply pipe 31, the main gas solenoid valve 32, and the gas proportional valve 33, which are shared with the combustion burner 30a.

[0043] Furthermore, the heating circuit 103 includes a circulation pump 310, a heating expansion tank 320, a thermal valve 330, a bypass thermal valve 345, pipes 340, 350, 360, 370, 380, and 390, a terminal thermal valve 305, and temperature sensors 382 and 384. The opening and closing of each of the thermal valve 330 and the bypass thermal valve 345 is controlled according to commands from the controller 300.

[0044] One end of the pipe 350 is connected to one end (inlet side) of the primary heat exchanger 11b. The other end of the pipe 350 is connected to a plurality of heating output ports (low temperature) 304 via a plurality of terminal thermal valves 305. The pipe 360 ​​is disposed between the other end (outlet side) of the primary heat exchanger 11b and the pipe 380. The pipes 360 and 370 branch off on the same side (outlet side) of the primary heat exchanger 11b, and the pipe 370 connects between the other end of the primary heat exchanger 11b and the heating output port 306 (high temperature).

[0045] Piping 380 connects between heating return port 302 and one end (inlet side) of secondary heat exchanger 21b. Piping 340 is connected between heating expansion tank 320 and pipe 370. One end of pipe 390 is connected to the other end (outlet side) of secondary heat exchanger 21b, and the other end of pipe 390 is connected to pipe 340 at connection point 395.

[0046] In the pipe 340, a bypass thermal valve 345 is inserted and connected between a connection point 395 with the pipe 390 and the pipe 370. A groove 346 is formed in the valve body or valve seat of the bypass thermal valve 345. The groove 346 constitutes a flow path connecting the inlet side and the outlet side of the bypass thermal valve 345 even when the bypass thermal valve 345 is closed. Therefore, the bypass thermal valve 345 is controlled to open and close according to a command from the controller 300, and a constant flow rate is ensured by the bypass flow path even in the closed state. That is, even when the bypass thermal valve 345 is closed, the groove 346 ensures a flow path for the heat medium between the connection point 395 and the pipe 370. The groove 346 may be clogged with dust or other foreign matter.

[0047] The suction port 311 of the circulation pump 310 is connected to the heating expansion tank 320. The discharge port 312 of the circulation pump 310 is connected to the branched portion 355 of the piping 350. The heating expansion tank 320 is connected to the suction port 311 of the circulation pump 310. The heating expansion tank 320 temporarily stores the heat medium circulating through the heating circuit 103. When the water level in the heating expansion tank 320 drops, water can be supplied from the piping 51 by opening the water supply valve 327. When the water level rises, the heat medium can be discharged from the overflow tank 328 to the drain plug 106 via the piping 325. In addition, drain (condensed water) generated inside the can body 10 is stored in a drain tank (not shown) and discharged to the outside after neutralization treatment.

[0048] A thermal valve 330 that is controlled to open and close in response to a command from the controller 300 is interposed and connected to the piping 360. When the thermal valve 330 is opened, the heat medium heated in the primary heat exchanger 11b is divided into a path that is output to the heating output port 306 (high temperature) by the piping 370 and a path that is circulated via the piping 360. Therefore, when the thermal valve 330 is opened, a path is further formed that circulates the heat medium output from the primary heat exchanger 11b to the secondary heat exchanger 21b via the bath heat exchanger 410, the junction 385, and the piping 380.

[0049] On the other hand, when the thermal valve 330 is in a closed state, the heat medium output from the primary heat exchanger 11b is supplied only to the pipe 370. The heat medium supplied to the pipe 370 is output to the heating output port (high temperature) 306 and the pipe 340.

[0050] A temperature sensor 384 is disposed on the output side of primary heat exchanger 11b for detecting the output temperature from water heater body 10 in heating circuit 103, i.e., the heat medium temperature after heating (hereinafter also referred to as "high-temperature side heat medium temperature Twh"). Meanwhile, a temperature sensor 382 is disposed in heating expansion tank 320 for detecting the heat medium temperature in the tank (hereinafter also referred to as "low-temperature side heat medium temperature Twl"). The low-temperature side heat medium temperature Twl detected by temperature sensor 382 corresponds to the temperature of the heat medium supplied from heating outlet (low temperature) 304. The temperature sensors 382 and 384 are constituted by, for example, thermistors.

[0051] Controller 300 receives output signals (detection values) from each sensor and user operations, and generates control commands to each device to control the overall operation of hot water supply system 100. User operations include commands to turn hot water supply system 100 on / off and a set hot water temperature (Tr*) command. For example, user operations are input to a remote controller (not shown).

[0052] The control commands include, for example, opening / closing and opening degree commands for each valve, commands for the combustion burners 30a, 30b (combustion on / off and heat generation amount), and on / off commands for the circulation pump 310. The operation on / off commands include on / off commands for the hot water supply operation and hot water pouring operation by the hot water supply circuit 101, the reheating operation by the reheating circuit 102, and the heating operation by the heating circuit 103. Regarding the heating operation, the heating operation in the hot water supply system 100 may be automatically turned on in response to an on command for the high-temperature heating device 510 and the low-temperature heating device 610 (FIG. 2). It is preferable that the set hot water temperature (Tr*) is set separately for each of the hot water supply operation and the hot water pouring operation. In addition, in the heating operation, the set temperature is generally not directly input.

[0053] During hot water supply operation and hot water pouring operation, low-temperature water in the water inlet pipe 50 is heated by combustion in the combustion burner 30a of the hot water supply circuit 101 and output to the hot water outlet pipe 70. The controller 300 calculates the required amount of heat generation P* by the combustion burner 30a during hot water supply operation and hot water pouring operation. For example, the required amount of heat generation P* is calculated so that the detected value of the boiler body outlet temperature is controlled to a target value. The target value of the boiler body outlet temperature can be set based on the set temperatures during hot water supply operation and hot water pouring operation set by the user and the flow division ratio of the bypass pipe 60 (opening degree of the distribution valve 80).

[0054] During the reheating operation and the heating operation, the heat medium circulating through the circulation path formed by driving the circulation pump 310 is heated by combustion in the combustion burner 30b. The controller 300 calculates the heat generation amount P* required by the combustion burner 30b so that the detection value of the output temperature (high-temperature side heat medium temperature Twh) of the primary heat exchanger 11b detected by the temperature sensor 384 is controlled to a target value.

[0055] The controller 300 calculates the amount of gas supplied to the combustion burners 30a, 30b according to the calculated required heat generation amount P* in each of the hot water supply operation, hot water pouring operation, heating operation, and reheating operation. Furthermore, the controller 300 determines a combination of the number of burners to be burned and the gas flow rate among the combustion burners 30a, 30b that will realize this amount of gas supplied, and controls the aperture of the gas proportional valve 33 and the opening and closing of the capacity switching valves 35a-35c, 36a, 36b so that the determined number of burners to be burned and the gas flow rate are realized. Furthermore, the controller 300 controls the rotation speed of the blower fan 40 so that the ratio (air-fuel ratio) of the amount of air blown by the blower fan 40 to the calculated amount of gas supplied becomes a predetermined value (for example, the ideal air-fuel ratio).

[0056] In the hot water supply system 100, when the heating operation is on, the circulation pump 310 operates to circulate the heat medium (hot water) from the heating circuit 103 to the high-temperature heating device 510 and / or the low-temperature heating device 610 via the heating return port 302, and the heating output port (low temperature) 304 and / or the heating output port (high temperature) 306, via the "heating circulation path" described below.

[0057] By driving the circulation pump 310, a suction path is formed from the heating return port 302 through the piping 380, the secondary heat exchanger 21b, the piping 390, the connection point 395, the piping 340, and the heating expansion tank 320 to the suction port 311 of the circulation pump 310. The heat medium sucked from the heating expansion tank 320 into the circulation pump 310 is output from the discharge port 312 to the branching portion 355 of the piping 350.

[0058] The heat medium discharged from the circulation pump 310 is branched at the branching portion 355 of the piping 350 into an output path leading to the terminal thermal valve 305 and the heating output port (low temperature) 304, and a heating path passing through the primary heat exchanger 11b. The heating path includes an output path that outputs the heat medium from the heating output port (high temperature) 306 after passing through the primary heat exchanger 11b, and a return path that leads to the heating expansion tank 320 again via the piping 340 (bypass thermal valve 345) after passing through the primary heat exchanger 11b. As described above, the return path is formed even when the bypass thermal valve 345 is closed, but when the bypass thermal valve 345 is opened, the flow rate of the return path can be increased. For example, when the temperature of the heat medium is low immediately after the heating operation is turned on, the temperature of the heat medium can be quickly increased by opening the bypass thermal valve 345.

[0059] By forming the above-mentioned heater circulation path, high-temperature water that has passed through the primary heat exchanger 11b is supplied from the heater output port 306 (high temperature) to the high-temperature heater 510. On the other hand, hot water in the heater expansion tank 320 is supplied from the heater output port 304 (low temperature) to the low-temperature heater 610.

[0060] When the heating operation is off, the flow of the heat medium is stopped in each of the heating circuit 103, the high-temperature heating device 510, and the low-temperature heating device 610. Therefore, in a severe cold season or the like, if the heating operation is off for a long period of time, there is a concern that the heat medium will freeze. Therefore, in the heating circuit 103, when the heating operation is off, a freeze prevention operation is automatically performed in which the heat medium is circulated in the heating circuit 103 and the low-temperature heating device 610. For example, the freeze prevention operation is automatically started when a predetermined start condition is met using at least one of the heat medium temperatures Twh, Twl, the air temperature detected by an ambient temperature sensor (not shown), and the elapsed time since the circulation of the heat medium was stopped during the heating operation off period.

[0061] [Function block] The configuration of hot water supply system 100 will be further described with reference to Fig. 3. Fig. 3 is a block diagram that typically illustrates a control structure of controller 300 included in hot water supply system 100. Controller 300 receives an input from temperature sensor 384. Controller 300 includes memory 301, timer 303, and monitor 630. Controller 300 controls bypass thermal valve 345 and circulation pump 310. Controller 300 may include a microcomputer.

[0062] Memory 301 is realized by a non-volatile memory. In one aspect, memory 301 holds the date and time when a clog removal operation was performed in hot water supply system 100 as a foreign matter removal operation history. Timer 303 measures the time elapsed for performing a clog removal operation of bypass thermal valve 345. Monitor 630 displays the status of hot water supply system 100. In one aspect, monitor 630 may display a message indicating that it is time to replace the heat medium, or a message urging inspection or cleaning of the circulation circuit.

[0063] (1) In a certain aspect, the controller 300 detects clogging in the groove portion 346 based on a rate of change in temperature of the heat medium at the start of a heating operation in which the heat medium circulates. Based on the detection of the clogging, the controller 300 changes the first thermal valve (bypass thermal valve 345) to an open state and operates the circulation pump 310 as a foreign object removal operation after the heating operation.

[0064] (2) In one aspect, the temperature sensor 384 may be disposed in the hot terminal path. The controller 300 detects the occurrence of clogging in the groove 346 based on the time required for the temperature of the heat medium to rise being shorter than a predetermined time in order to detect the clogging in the groove 346 based on the rate of change of temperature.

[0065] (3) In a certain aspect, the controller 300 issues a notification regarding replacement of the heat medium based on the fact that the foreign object removal operation has been performed a preset number of times or more during a predetermined first period. As an example, the controller 300 may issue the notification by outputting a synthetic voice through a speaker (not shown). As another example of the notification, the controller 300 may display a message on a monitor provided therein, prompting the user to replace the heat medium. Alternatively, the controller 300 may display a message on the monitor prompting the user to inspect or clean the circulation path. As yet another example, the controller 300 may transmit a message notifying the user that it is time to replace the heat medium via the Internet to a server (not shown) that manages the state of the hot water supply system 100. In this case, a maintenance company that operates the server can request the user of the hot water supply system 100 to replace the heat medium.

[0066] (4) In a certain aspect, controller 300 stores the number of times that foreign matter removal operation has been performed in memory 301. Controller 300 erases the number of times that foreign matter removal operation has been performed based on the fact that foreign matter removal operation has not been performed a predetermined number of times during a first period. In this embodiment, the first period is a period (e.g., one month, two months, etc.) that is set in advance as a period during which hot water supply system 100 is used on a trial basis. As an example, such a period may be set in winter when heating operation is frequently used.

[0067] (5) In one aspect, a second thermal valve (thermal valve 520) is disposed in the high-temperature terminal path. When the second thermal valve is closed to start the heating operation, controller 300 detects the temperature of the heat medium based on the output from temperature sensor 384.

[0068] (6) The controller 300 performs the foreign matter removal operation based on the fact that the foreign matter removal operation has not been performed during a second predetermined period of time. In this embodiment, the second period of time is, for example, a period (e.g., two weeks, one month, etc.) that is set in advance starting from the time when the bypass thermal valve 345 was last opened.

[0069] [Control Structure] The control structure of hot water supply system 100 will be described with reference to Fig. 4 and Fig. 5. Fig. 4 is a flowchart showing a part of the process executed by controller 300 to realize the foreign matter removal operation. In one aspect, the following process is realized by a computer executing a program including instructions for realizing each step. In another aspect, the process is also realized by a combination of circuit elements configured to realize each step.

[0070] In step S410, controller 300 determines whether a predetermined time (predetermined time) has elapsed since the previous operation of opening bypass thermal valve 345. This determination is made, for example, based on the foreign matter removal operation history stored in memory 301 and the time measured by timer 303. If controller 300 determines that the predetermined time has elapsed (YES in step S410), it switches control to step S420. If not (NO in step S410), controller 300 returns control to step S410 and executes the determination process again. Hereinafter, steps S420 to S480 correspond to the operation of removing clogging of bypass thermal valve 345 (step S580).

[0071] In step S420, controller 300 determines whether or not the heating operation is off, based on the operation settings of hot water supply system 100. If controller 300 determines that the heating operation is off (YES in step S420), it switches control to step S440. Otherwise (NO in step S420), controller 300 switches control to step S430.

[0072] In step S430, controller 300 waits for the heating operation to be stopped. In one aspect, controller 300 outputs a message prompting the user to stop the heating operation. In another aspect, controller 300 may output a message notifying the user of the stop of the heating operation and then stop the heating operation.

[0073] In step S440, the controller 300 transmits an open control signal to the bypass thermal valve 345 to open the bypass thermal valve 345.

[0074] In step S450, controller 300 starts the heating pump operation by driving circulation pump 310. Controller 300 uses timer 303 to measure the time that has elapsed since the heating pump operation was started.

[0075] In step S460, controller 300 detects, based on the time measured by timer 303, that a preset certain period of time required for the clogging removal operation has elapsed.

[0076] In step S470, controller 300 sends a stop signal to circulation pump 310 to stop circulation pump 310, and ends the heating pump operation.

[0077] In step S480, the controller 300 closes the bypass thermal valve 345. The controller 300 ends the control for the clog removal operation.

[0078] FIG. 5 is a flowchart showing a part of the process executed by the controller 300 when a heating operation is instructed.

[0079] In step S510, controller 300 detects an instruction to perform heating operation based on a switch operation by a user or an external signal, or the arrival of a time set in advance on a timer.

[0080] In step S520, controller 300 starts the combustion operation of hot water supply system 100.

[0081] In step S530, controller 300 detects the temperature of the heat medium after heating, based on the output from temperature sensor 384. Controller 300 continuously detects the temperature of the heat medium.

[0082] In step S540, controller 300 determines whether the degree of temperature increase corresponds to the degree of temperature increase when bypass thermal valve 345 is clogged. For example, if the time it takes for the temperature of the heat medium to increase by a certain temperature is shorter than a time previously assumed as a normal time, controller 300 determines that the degree of temperature increase detected corresponds to the degree of temperature increase when bypass thermal valve 345 is clogged. If controller 300 determines that the degree of temperature increase corresponds to the degree of temperature increase when bypass thermal valve 345 is clogged (YES in step S540), it switches control to step S550. If not (NO in step S540), controller 300 switches control to step S590.

[0083] In step S550, controller 300 increments the clog removal operation counter by 1 to record the clog removal operation to be executed. Controller 300 holds the record of the clog removal operation in memory 301 as foreign object removal operation history.

[0084] In step S560, controller 300 determines whether the number of times the clog removal operation has been performed within a predetermined period of time is N (a number of times predetermined as an upper limit). If controller 300 determines that the number of times the clog removal operation has been performed is N (YES in step S560), it switches control to step S570. If not (NO in step S560), controller 300 switches control to step S580.

[0085] In step S570, controller 300 issues a notice to replace the heat medium or a notice to encourage inspection (or cleaning) of the circulation circuit, assuming that the number of times the clogging removal operation has been performed indicates the need for replacement of the heat medium. For example, controller 300 outputs the notice as audio from a speaker (not shown), or displays a message encouraging the replacement. In another aspect, controller 300 may transmit a signal to a server managed by a maintenance company of hot water supply system 100 via an Internet line, notifying that it is time to replace the heat medium in hot water supply system 100. In one aspect, controller 300 may separately notify the notice to replace the heat medium and the notice encouraging inspection (or cleaning) of the circulation circuit, and in another aspect, may notify both notices together.

[0086] In step S580, the controller 300 executes the operation of clearing the blockage of the bypass thermal valve 345 (FIG. 4).

[0087] In step S590, controller 300 executes control for normal operation.

[0088] [Example of notification] An example of a notification mode of hot water supply system 100 will be described with reference to FIG. 6. FIG. 6 is a diagram showing an example of a message displayed on monitor 630 of controller 300. In one aspect, when controller 300 detects that it is time to replace the heat medium (heating water) (YES in step S560), monitor 630 displays the notification as shown in FIG. 6(A) (step S570). This allows the user of hot water supply system 100 to know that it is time to replace the heat medium. In another aspect, when controller 300 detects that it is time to inspect (or clean) the circulation circuit, monitor 630 displays the notification as shown in FIG. 6(B) (step S570). This allows the user to know that it is time to inspect (or clean) the circulation circuit.

[0089] As described above, according to the hot water supply system 100 of the present embodiment, the controller 300 monitors the rise in the temperature of the heating water at the start of the heating operation, and detects the rate of change of the temperature (for example, whether or not the temperature rises to a predetermined temperature or higher within a predetermined time). If the rate of change is equal to or higher than a reference value, that is, if the temperature of the heat medium rises to the predetermined temperature or higher, the controller 300 determines that the groove 346 of the bypass thermal valve 345 is clogged with foreign matter. In order to remove the foreign matter, the controller 300 opens the bypass thermal valve 345 and operates the circulation pump 310 to perform a circulation operation. As a result, a large amount of the heat medium flows through the bypass circuit, and the foreign matter is washed away. This can suppress the occurrence of the boiler body boiling phenomenon at the start of the heating operation due to clogging of the bypass circuit.

[0090] The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present invention is defined by the claims, not the above description, and is intended to include all modifications within the meaning and scope of the claims. [Industrial Applicability]

[0091] The disclosed technical features are applicable to hot water heating systems. [Explanation of symbols]

[0092] 10 boiler body, 11a, 11b primary heat exchanger, 15 exhaust path, 21a, 21b secondary heat exchanger, 30a, 30b combustion burner, 31 gas supply pipe, 32 main gas solenoid valve, 33 gas proportional valve, 35a, 35c, 36a, 36b capacity switching valve, 40 blower fan, 50 water inlet pipe, 51, 190, 325, 340, 350, 360, 370, 380, 390 piping, 60 bypass pipe, 70 hot water outlet pipe, 75, 185, 385 junction, 80 distribution valve, 90 flow control valve, 100 hot water supply system, 101 hot water supply circuit, 102 reheating circuit, 103 heating circuit, 105 faucet, 106 Drain plug, 110, 120, 130, 374, 382, ​​384 Temperature sensor, 150 Flow sensor, 180 Hot water pipe, 191 Bath water inlet, 192 Bath water outlet, 195 Bath supply piping, 210 Hot water solenoid valve, 220 Check valve, 300 Controller, 301 Memory, 302 Heating return port, 303 Timer, 304, 306 Heating output port, 305 Terminal thermal valve, 310 Circulation pump, 311 Inlet, 312 Outlet, 320 Heating expansion tank, 327 Water supply valve, 328 Overflow tank, 330 Thermal valve, 345 Bypass thermal valve, 346 Groove, 355 Branch, 395 Connection point, 400 Reheating circulation pump, 410 Bath heat exchanger, 500 High temperature heating terminal, 510 High temperature heating device, 520 thermal valve, 600 low temperature heating terminal, 610 low temperature heating device, 630 monitor.

Claims

1. A hot water heating device, A combustion section; A heat exchanger; a circulation path including a high-temperature terminal path and a low-temperature terminal path for circulating a heat transfer medium; a bypass path for connecting the high-temperature terminal path and the low-temperature terminal path; A pump disposed in the circulation path; a first thermal valve provided in the bypass path; A temperature sensor for detecting a temperature of the heat medium; A control device for controlling the hot water heating device, a groove for allowing the heat medium to flow is provided in a valve body or a valve seat of the first thermal valve; The control device includes: detecting clogging in the groove based on a rate of change in temperature of the heat medium when a heating operation in which the heat medium circulates is started; The hot water heating apparatus changes the first thermal valve to an open state and operates the pump as a foreign object removal operation after the heating operation based on the detection of the blockage.

2. the temperature sensor is disposed in the hot terminal path; The hot water heating device of claim 1, wherein detecting clogging in the groove based on the rate of change of the temperature includes detecting the occurrence of clogging in the groove based on the time required for the temperature of the heat medium to increase being faster than a predetermined time.

3. The hot water heating apparatus according to claim 1 , further comprising a notification unit that issues a notification regarding replacement of the heat medium based on the fact that the foreign matter removal operation has been performed a preset number of times or more during a predetermined first period.

4. The hot water heating apparatus according to claim 1 , further comprising a notification unit that issues a notification regarding an inspection of the circulation path based on the fact that the foreign object removal operation has been performed a preset number of times or more during a predetermined first period.

5. A storage unit for storing the number of times the foreign matter removal operation has been performed is further provided, 5. The hot water heating apparatus according to claim 3, wherein the control device erases the number of times the foreign object removal operation has been performed based on the fact that the foreign object removal operation has not been performed a predetermined number of times during the first period.

6. A second thermal valve is disposed in the high temperature terminal path, The hot water heating apparatus according to claim 1 , wherein the control device detects the temperature of the heat medium based on an output from the temperature sensor when the second thermal valve is closed at the start of the heating operation.

7. The hot water heating apparatus according to claim 1 , wherein the control device performs the foreign matter removal operation on the basis that the foreign matter removal operation has not been performed during a second predetermined period of time.

Images