Control method of gas water heater and gas water heater

Abstract

The present application relates to the technical field of water heaters, and particularly discloses a control method of a gas water heater and the gas water heater. The gas water heater comprises a main heat exchanger, a condensation heat exchanger, a water inlet main pipe, an atomizer and a water path switching assembly. The atomizer atomizes condensate water. In the water path switching assembly, a first water path directly connects the water inlet main pipe and the main heat exchanger, and a second water path sequentially connects the water inlet main pipe, the condensation heat exchanger and the main heat exchanger. After the atomizer fails, the first water path is controlled to be opened, and the minimum water passing area of the second water path is adjusted based on the real-time liquid level of the condensate water, so that the real-time liquid level tends to be within a safe range, and the generation amount and evaporation amount of the condensate water are dynamically balanced as a whole. Even if the atomizer fails, the condensate water level can be controlled within a safe range, so that the condensation heat exchanger can still work to recover heat in flue gas to generate condensate water. The risk of triggering shutdown due to excessive condensate water and the risk of damage of the water collecting cavity due to insufficient condensate water are reduced.

Description

Technical Field

[0001] This invention relates to the field of water heater technology, and more particularly to a control method for a gas water heater and a gas water heater. Background Technology

[0002] In the water heater with a condensing heat exchanger disclosed in existing patent document (CN120868618A), the water circuit switching component connects the inlet main pipe, the condensing heat exchanger, and the main heat exchanger sequentially in the first operating mode to form a first flow path. In the second operating mode, the water circuit switching component connects the inlet main pipe to the main heat exchanger to form a second flow path, and disconnects the inlet and / or outlet of the condensing heat exchanger from the second flow path. When the water circuit switching component operates in the first operating mode, the condensing heat exchanger works normally and produces condensate. When the liquid level in the water collection chamber reaches a first preset level, the atomization module is activated to atomize the condensate in the water collection chamber and discharge it through the exhaust port. When the liquid level in the water collection chamber reaches a second preset level and there is a risk of backflow, the water circuit switching component switches to the second operating mode. The condensing heat exchanger stops producing condensate, and the exhaust temperature increases, which helps to atomize and discharge the residual condensate in the water collection chamber, reducing the liquid level in the water collection chamber and ensuring combustion safety.

[0003] The water heaters disclosed in the aforementioned patent documents do not have a method for handling atomizer malfunctions. When the atomizer malfunctions, the gas water heater will shut down completely, preventing users from using hot water normally. Even if the water circuit switching component is switched to the second working mode when the atomizer malfunctions, the condenser heat exchanger stops heat exchange and no longer recovers the vaporization waste heat in the flue gas. This method will still significantly reduce the thermal efficiency of the gas water heater. In addition, the walls of the water collection chamber are mostly made of plastic. If there is no condensate in the water collection chamber, the walls are prone to deformation and damage when heated in the high-temperature flue gas environment.

[0004] Therefore, it is crucial to control the condensate in the water collection chamber within a safe range without stopping the gas water heater after an atomizer malfunction. This would prevent the condensate from flowing back into the combustion chamber of the water heater body due to excessively high liquid levels, and avoid the chamber walls from deforming and being damaged due to excessively low liquid levels caused by the high-temperature flue gas environment. Summary of the Invention

[0005] One of the technical problems solved by this invention is to provide a control method for a gas water heater, which can enable the condenser heat exchanger to continue to work and recover heat from the flue gas and generate condensate water when the atomizer fails, while ensuring a safe liquid level. This reduces the risk of deformation and damage to the cavity wall when there is no condensate water in the water collection chamber.

[0006] The second technical problem solved by this invention is to provide a gas water heater that, when the atomizer fails, can still operate to recover heat from the flue gas and generate condensate while ensuring a safe liquid level, thereby reducing the risk of deformation and damage to the cavity wall when there is no condensate in the water collection chamber.

[0007] The first technical problem mentioned above is solved by the following technical solution: A control method for a gas water heater, the gas water heater comprising a main heat exchanger, a condensing heat exchanger, a main inlet pipe, an atomizer, and a water circuit switching assembly, wherein the condensing heat exchanger has a water collection chamber for collecting condensate produced by the condensing heat exchanger, the atomizer for atomizing the condensate, and the water circuit switching assembly comprising a first water circuit and a second water circuit, the first water circuit for directly connecting the main inlet pipe to the main heat exchanger, and the second water circuit for sequentially connecting the main inlet pipe, the condensing heat exchanger, and the main heat exchanger, the control method comprising: After the gas water heater is in operation, the real-time liquid level of the condensate in the water collection chamber is obtained; After the atomizer malfunctions, the first water path is opened, and the minimum water flow area of ​​the second water path is adjusted based on the real-time liquid level to keep the real-time liquid level within a safe range.

[0008] The control method for gas water heaters described in this invention has the following advantages compared to the prior art: When the gas water heater malfunctions, it controls the opening of the first water circuit and adjusts the minimum water flow area of ​​the second water circuit based on the real-time liquid level. The minimum water flow area is negatively correlated with the real-time liquid level. Since high-temperature flue gas also evaporates condensate, the amount of condensate generated and evaporated fluctuates in real time. However, by continuously adjusting the minimum water flow area of ​​the second water circuit to change the water flow rate, the rate of condensate generation can be controlled. This results in a dynamic balance between the overall amount of condensate generated and evaporated. Even with atomizer malfunction, the condensate level can be kept within a safe range, allowing the condensing heat exchanger to continue operating, recovering heat from the flue gas and generating condensate. This reduces the risk of shutdown due to excessive condensate in the event of an atomizer malfunction, and the risk of the water collection chamber being damaged by heat in the high-temperature flue gas environment due to insufficient condensate, thus improving the safety performance of the gas water heater.

[0009] The second technical problem mentioned above is solved by the following technical solution: A gas water heater includes a main heat exchanger, a condensing heat exchanger, a main inlet pipe, an atomizer, a water circuit switching assembly, and a controller. The water circuit switching assembly is communicatively connected to the controller. The condensing heat exchanger has a water collection chamber for collecting condensate generated by the condensing heat exchanger. The atomizer atomizes the condensate. The water circuit switching assembly includes a first water circuit and a second water circuit. The first water circuit directly connects the main inlet pipe to the main heat exchanger. The second water circuit sequentially connects the main inlet pipe, the condensing heat exchanger, and the main heat exchanger. The controller executes the control method for the gas water heater described in this invention.

[0010] Compared with the prior art, the gas water heater of the present invention has the following beneficial effects: In this embodiment, when the atomizer malfunctions, the gas water heater controls the opening of the first water circuit and adjusts the minimum water flow area of ​​the second water circuit based on the real-time liquid level. The minimum water flow area is negatively correlated with the real-time liquid level. Since high-temperature flue gas also evaporates condensate, the amount of condensate generated and evaporated fluctuates in real time. However, by continuously adjusting the minimum water flow area of ​​the second water circuit to change the water flow rate, the rate of condensate generation can be controlled. This results in a dynamic balance between the overall amount of condensate generated and evaporated. Even with atomizer malfunction, the condensate level can be controlled within a safe range, allowing the condenser heat exchanger to continue operating, recovering heat from the flue gas and generating condensate. This reduces the risk of shutdown due to excessive condensate in case of atomizer malfunction, and the risk of the water collection chamber being damaged by heat in a high-temperature flue gas environment due to insufficient condensate, thus improving the safety performance of the gas water heater.

[0011] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0012] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0013] Figure 1 This is a flowchart of a control method for a gas water heater provided in Embodiment 1 of the present invention; Figure 2 This is a schematic diagram of the structure of the gas water heater provided by the present invention; Figure 3 This is a schematic diagram of water flow when the water path switching component is in different states; Figure 4 This is a flowchart of a control method for a gas water heater provided in Embodiment 2 of the present invention; Figure 5 This is a schematic diagram of a liquid level probe detecting the liquid level. Figure 6 This is a schematic diagram of a guide rod type float leveling device; Figure 7 This is a flowchart of a control method for a gas water heater provided in Embodiment 3 of the present invention; Figure 8 This is a flowchart of a control method for a gas water heater provided in Embodiment 4 of the present invention. Detailed Implementation

[0014] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0015] Example 1 Figure 1 A flowchart of a control method for a gas water heater provided in Embodiment 1 of the present invention is shown below. Figure 1 As shown, the control method of this gas water heater includes: S101. After the gas water heater starts working, obtain the real-time liquid level of condensate in the water collection chamber.

[0016] The gas water heater in this embodiment is a water heater with a condensing heat exchanger, which recovers heat from the flue gas generated by gas combustion. Figure 2 As shown, a gas water heater may include a main heat exchanger 1, a condensing heat exchanger 2, a main inlet pipe 3, an atomizer 4, a water circuit switching component 5, and a controller 6. The main heat exchanger 1 is the main component used to realize combustion and heat exchange. The flue gas generated by combustion in the main heat exchanger 1 enters the condensing heat exchanger 2 through the flue 7. The flue gas exchanges heat with the heat exchange tubes in the condensing heat exchanger 2 to realize the recovery of flue gas heat. At the same time, condensate is generated and collected by the water collection chamber 21 in the condensing heat exchanger 2. The atomizer 4 is used to atomize the condensate in the water collection chamber 21 and discharge it into the atmosphere. The cold water flowing into the condensing heat exchanger 2 increases in temperature after heat exchange and then flows into the main heat exchanger 1.

[0017] The water path switching component 5 is communicatively connected to the controller 6. The water path switching component 5 includes a first water path and a second water path. The first water path directly connects the main inlet pipe 3 to the main heat exchanger 1. The second water path sequentially connects the main inlet pipe 3, the condenser heat exchanger 2, and the main heat exchanger 1. In one embodiment, as shown... Figure 2 As shown, the water circuit switching component 5 includes a first pipe 52, a second pipe 53, a third pipe 54, and a water circuit switching valve 51. The water circuit switching valve 51 is connected to the main water inlet pipe 3 and is communicatively connected to the controller 6. The first pipe 52 is connected to the inlet of the condensing heat exchanger 2 and the water circuit switching valve 51. The second pipe 53 is connected to the outlet of the condensing heat exchanger 2 and the inlet of the main heat exchanger 1. That is, the first pipe 52, the condensing heat exchanger 2, and the second pipe 53 are connected in sequence to form the second water circuit. The third pipe 54 is connected to the water circuit switching valve 51 and the inlet of the main heat exchanger 1 to form the first water circuit. The controller 6 can close and open the first water circuit and the second water circuit by controlling the water circuit switching valve 51.

[0018] After the gas water heater is working, the real-time liquid level of condensate in the water collection chamber can be detected by a liquid level gauge. The liquid level gauge can be of various forms, and this embodiment does not limit the liquid level gauge.

[0019] S102. After the atomizer malfunctions, control the first water path to open and adjust the minimum water flow area of ​​the second water path based on the real-time liquid level to keep the real-time liquid level within a safe range.

[0020] In one embodiment, the second water passage is equipped with a flow regulating valve, which can adjust the minimum water passage area of ​​the second water passage by adjusting the opening of the flow regulating valve.

[0021] In another embodiment, the second waterway includes multiple parallel waterway branches, each equipped with a switch valve. The minimum water passage area of ​​the second waterway can be adjusted by controlling the switch valves of each waterway branch. It is understood that the minimum water passage area of ​​the second waterway is the sum of the minimum water passage areas of all the waterway branches.

[0022] Atomizer malfunction refers to the atomizer's inability to atomize condensed water. In one embodiment, the atomizer is communicatively connected to a controller. The controller receives current signal values ​​fed back by the atomizer. If the deviation between the current signal value and a preset current signal value exceeds a preset threshold, the atomizer is determined to be faulty. In another embodiment, the atomizer malfunction can also be determined by changes in the condensed water level. For example, the rate of increase in the condensed water level in the collection chamber can be obtained. If the rate of increase exceeds a preset rate, it can be determined that the atomizer is faulty and unable to atomize the condensed water.

[0023] Figure 3 This is a schematic diagram of water flow when the water path switching component is in different states. Figure 3Figure (a) is a schematic diagram of the water flow when the second waterway is open and the first waterway is closed. Figure 3 Figure (b) is a schematic diagram of the water flow when the first waterway is open and the second waterway is closed. Figure 3 Figure (c) is a schematic diagram of the water flow when the first and second water channels are open.

[0024] In the event of an atomizer malfunction, if the first water circuit is closed, the water circuit switching valve 51 is controlled to open the first water circuit. For example, the water circuit switching valve 51 can be a three-way valve, which connects the main water inlet pipe 3, the first water circuit, and the second water circuit. The controller 6 can control the three-way valve to open the first water circuit. In another example, as a replacement for the water circuit switching valve 51, a solenoid valve is installed in the first water circuit, and a flow regulating valve is installed in the second water circuit. The controller 6 opens the first water circuit by controlling the solenoid valve in the first water circuit and adjusts the minimum water flow area of ​​the second water circuit by controlling the opening degree of the flow regulating valve. It should be noted that if the first water circuit is currently open, it remains open.

[0025] In this embodiment, after the atomizer malfunctions, the second water path is also in the open state, and the size of the minimum water passage area of ​​the second water path is adjusted based on the real-time liquid level of the condensate to dynamically regulate the condensate generation rate. For example, when the condensate level is high, the minimum water passage area of ​​the second water path is small, and when the condensate level is low, the minimum water passage area of ​​the second water path is large, so as to reduce the amount of condensate generated when the liquid level is high and increase the amount of condensate generated when the liquid level is low, so that the condensate level is kept within a safe range.

[0026] In one optional embodiment, a first liquid level and a second liquid level can be set, with the first liquid level being lower than the second liquid level. When the real-time liquid level is lower than the first liquid level, the minimum water passage area of ​​the second water passage is increased to the first minimum water passage area. When the real-time liquid level is higher than the second liquid level, the minimum water passage area of ​​the second water passage is decreased to the second minimum water passage area. In this case, the first liquid level is lower than the second liquid level, and the first minimum water passage area is greater than the second minimum water passage area.

[0027] The first liquid level can be the level that triggers the atomizer to start and enter the atomization working state. The second liquid level can be the condensate backflow warning level, and the second liquid level is lower than the shutdown trigger level but higher than the first liquid level. That is to say, if the condensate rises to the second liquid level and continues to rise, there is a risk of backflow into the main heat exchanger 1, or even triggering a shutdown. The first and second minimum water passage areas can be pre-configured in the controller. When the condensate level is lower than the first liquid level, if the condensate level continues to drop by a certain amount, the water collection chamber will be deformed and damaged by the high temperature of the flue gas. It is necessary to increase the minimum water passage area of ​​the second water path to increase the amount of condensate generated.

[0028] It is understood that in this embodiment, the upper limit of the above-mentioned safety range is higher than the second liquid level of this embodiment, and the lower limit of the safety range is lower than the first liquid level of this embodiment. Therefore, when the condensate liquid level is higher than the second liquid level and lower than the first liquid level, it is not necessarily outside the safety range.

[0029] like Figure 3 As shown in Figure (c), after an atomizer malfunctions, when the real-time liquid level is lower than the first liquid level, it indicates that there is insufficient condensate in the water collection chamber. To prevent insufficient condensate, the minimum water passage area of ​​the second water path can be increased to the first minimum water passage area. For example, the water path switching valve 51 can be a proportional valve, and the controller can control the water path switching valve 51 to increase the minimum water passage area of ​​the second water path to the first minimum water passage area; or, a proportional valve or a multi-position solenoid valve can be installed in the second water path, and the controller can control the proportional valve or multi-position solenoid valve in the second water path to increase the minimum water passage area of ​​the second water path to the first minimum water passage area. This allows the condenser heat exchanger to generate condensate more quickly when the condensate level is low, while the high-temperature flue gas also causes the condensate to evaporate. When the amount of condensate generated is greater than the amount of evaporation, the condensate level tends to rise, allowing the condensate level to quickly rise back above the first liquid level.

[0030] When the real-time liquid level is higher than the second liquid level, it indicates that the condensate in the water collection chamber is high. To prevent further increase in condensate, the controller reduces the minimum water passage area of ​​the second water path to the second minimum water passage area. For example, the water path switching valve 51 can be a proportional valve. The controller can control the water path switching valve 51 to reduce the minimum water passage area of ​​the second water path to the second minimum water passage area. This allows the condensing heat exchanger to generate condensate at a slower rate when the condensate level is high. When the amount of condensate generated is less than the amount of evaporation, the condensate level tends to decrease, causing the condensate level to drop below the second liquid level. The first and second liquid levels are within a safe range.

[0031] In this embodiment, when the atomizer malfunctions, the gas water heater controls the opening of the first water circuit and adjusts the minimum water passage area of ​​the second water circuit based on the real-time liquid level. The minimum water passage area is negatively correlated with the real-time liquid level. Since high-temperature flue gas also evaporates condensate, the amount of condensate generated and evaporated fluctuates in real time. However, by continuously adjusting the minimum water passage area of ​​the second water circuit, a dynamic balance is maintained between the two. Even with atomizer malfunction, the condensate level can be controlled within a safe range, allowing the condenser heat exchanger to continue operating, recovering heat from the flue gas and generating condensate. This reduces the risk of shutdown due to excessive condensate during atomizer malfunction and damage to the water collection chamber due to heat deformation in the high-temperature flue gas environment when there is insufficient condensate, thus improving the safety performance of the gas water heater.

[0032] Example 2 Figure 4A flowchart of a control method for a gas water heater provided in Embodiment 2 of the present invention is shown below. Figure 4 As shown, the control method of this gas water heater includes: S401. After the gas water heater starts working, obtain the real-time liquid level of condensate in the water collection chamber.

[0033] In one embodiment, such as Figure 5 The schematic diagram shown illustrates the detection of liquid level using a liquid level probe. A liquid level gauge with a liquid level probe structure can be used to detect the real-time liquid level of condensate in the water collection chamber. The liquid level gauge with a liquid level probe structure includes a first liquid level probe 22, a second liquid level probe 23, and a common electrode 24 that extend into the water collection chamber 21. The distance from the end of the second liquid level probe 23, the first liquid level probe 22, and the common electrode 24 extending into the water collection chamber 21 to the bottom of the water collection chamber 21 decreases sequentially. The first liquid level probe 22 and the second liquid level probe 23 are used to detect the first liquid level and the second liquid level, respectively, with the second liquid level being higher than the first liquid level.

[0034] When the condensate water submerges the level probe, the condensate water acts as a conductive medium, causing the level probe and the common electrode 24 to form an electrical circuit. The level probe submerged in the condensate water outputs a level signal. That is, when the second level probe 23 outputs a level signal, the first level probe 22 also outputs a level signal synchronously. When the first level probe 22 does not output a level signal, the second level probe 23 also does not output a level signal. Based on the signal output status of each level probe, the real-time level height of the condensate water can be determined.

[0035] In another embodiment, such as Figure 6 The schematic diagram of the guide rod type float level device shown illustrates the real-time level detection of condensate in the water collection chamber. The device includes a guide rod 25 disposed within the water collection chamber 21, and a second signal triggering component 27 and a first signal triggering component 26 arranged sequentially from top to bottom on the guide rod 25. It also includes a float 28 that slides up and down the guide rod 25 as the liquid level rises and falls. When the float 28 floats up and down with the liquid level, passing the second signal triggering component 27 and the first signal triggering component 26, it outputs level signals indicating the second and first liquid levels, respectively. Each level sensor can be an electromagnetic induction switch or a mechanical switch. The float 28 has a magnet or a triggering structure that activates the mechanical switch. When the float 28 rises or falls with the liquid level, passing the level sensor, the corresponding level sensor outputs a level signal indicating the corresponding liquid level.

[0036] The above examples of liquid level probes and floats illustrate the principle of real-time liquid level detection of condensate in the water collection chamber. In practical applications, those skilled in the art can also use other methods to detect the real-time liquid level of condensate.

[0037] S402. After an atomizer malfunctions, control the first water circuit to open.

[0038] This embodiment can detect whether the atomizer is faulty in various ways. For example, it can detect whether the atomizer is faulty by the current signal value fed back by the atomizer. For example, when the deviation between the current signal value fed back by the atomizer and the preset current signal value is greater than a preset threshold, it is determined that the atomizer is faulty. Alternatively, it can detect whether the atomizer is faulty by the change in the condensate level. For example, the growth rate of the condensate level in the water collection chamber can be obtained. When the growth rate of the level is greater than a preset growth rate, it can be determined that the atomizer is faulty and cannot atomize the condensate.

[0039] The method for controlling the opening of the first water circuit after an atomizer malfunction can be referred to S102 in Embodiment 1, and will not be described in detail here.

[0040] S403. When the first liquid level probe does not output a signal, if it is determined that the real-time liquid level is lower than the first liquid level, the minimum water passage area of ​​the second water path is adjusted to the first minimum water passage area.

[0041] In this embodiment, the first minimum water flow area and the second minimum water flow area can be pre-configured in the controller. The first minimum water flow area is greater than the second minimum water flow area. The values ​​of the first minimum water flow area and the second minimum water flow area may be different for different models of gas water heaters.

[0042] It is understandable that in this embodiment, the first minimum water flow area is a value measured in advance through experiments. In various household water use scenarios, when the minimum water flow area of ​​the second water path is adjusted to the first minimum water flow area, the real-time liquid level of the condensate will increase, that is, the condensate generation rate is greater than the evaporation rate of the condensate by the flue gas.

[0043] In one embodiment, if such as Figure 5 When the level gauge shown does not output a signal from the first level probe 22, it indicates that the condensate has not submerged the first level probe 22, and it is determined that the real-time level of the condensate is lower than the first level. At this time, it is necessary to increase the condensate generation rate and replenish the condensate in the water collection chamber. The minimum water passage area of ​​the second water path can be increased to the first minimum water passage area.

[0044] Specifically, a flow regulating valve can be installed in the second water circuit. When the real-time liquid level is detected to be lower than the first liquid level, the controller can determine the first target opening degree corresponding to the first minimum water passage area and control the flow regulating valve to increase from the current opening degree to the first target opening degree.

[0045] If the current opening is 0, it means that the second water circuit is closed. The controller can control the flow regulating valve to open to the first target opening, so that the minimum water flow area of ​​the second water circuit increases from 0 to the first minimum water flow area. If the second water circuit is currently open, the controller controls the flow regulating valve to adjust from the current opening to the first target opening, so that the minimum water flow area of ​​the second water circuit is adjusted from 0 or from the current minimum water flow area to the first minimum water flow area. This helps to increase the amount of condensate generated in the condensing heat exchanger. When the amount of condensate generated is greater than the amount of evaporation, the condensate level tends to rise, so that the condensate level can quickly rise back to above the first level.

[0046] S404. When the second liquid level probe outputs a signal, if it is determined that the real-time liquid level is higher than the second liquid level, the minimum water passage area of ​​the second water path is reduced to the second minimum water passage area, wherein the first liquid level is lower than the second liquid level and the first minimum water passage area is greater than the second minimum water passage area.

[0047] In one embodiment, if such as Figure 5 When the level gauge shown outputs a signal from the second level probe 23, it indicates that the condensate has submerged the second level probe 23, confirming that the real-time level is higher than the second level. It is necessary to reduce the rate of condensate generation or stop the generation of condensate. The minimum water passage area of ​​the second water channel can be reduced to the second minimum water passage area.

[0048] It is understandable that in this embodiment, the second minimum water flow area is a value measured in advance through experiments. In various household water use scenarios, when the minimum water flow area of ​​the second water path is adjusted to the second minimum water flow area, the real-time liquid level of the condensate will decrease, that is, the condensate generation rate is less than the evaporation rate of the condensate by the flue gas.

[0049] Specifically, a flow regulating valve can be installed in the second water circuit. When the real-time liquid level is detected to be higher than the second liquid level, the second target opening degree corresponding to the second minimum water passage area is determined, and the flow regulating valve is controlled to reduce from the current opening degree to the second target opening degree.

[0050] If the second target opening is 0, it means that the second water circuit needs to be closed to stop the generation of condensate. The controller can control the opening of the flow regulating valve to be reduced to 0. If the second target opening is not 0, it means that the second water circuit remains open and the minimum water flow area in the second water circuit needs to be reduced. By closing the second water circuit or reducing the minimum water flow area of ​​the second water circuit, the condenser heat exchanger can stop generating condensate or reduce the amount of condensate generated. When the amount of condensate generated is less than the amount of evaporation, the condensate level tends to drop, so that the condensate level can be quickly reduced to below the second level.

[0051] Example 3 Figure 7A flowchart of a control method for a gas water heater provided in Embodiment 3 of the present invention is shown below. Figure 7 As shown, the control method of this gas water heater includes: S701. After the gas water heater is working, obtain the real-time liquid level of condensate in the water collection chamber.

[0052] In one embodiment, such as Figure 5 The schematic diagram shown illustrates the detection of liquid level using a liquid level probe. A liquid level gauge with a liquid level probe structure can be used to detect the real-time liquid level of condensate in the water collection chamber. In practical applications, those skilled in the art can also use other methods to detect the real-time liquid level of condensate.

[0053] S702. After an atomizer malfunctions, the first water circuit is opened.

[0054] The method for controlling the opening of the first water circuit after an atomizer malfunction can be referred to S102 in Embodiment 1, and will not be described in detail here.

[0055] S703: When the first liquid level probe does not output a signal, if it is determined that the real-time liquid level is lower than the first liquid level, the minimum water passage area of ​​the second water path is gradually increased until the liquid level of the condensate rises.

[0056] In one embodiment, if such as Figure 5 When the level gauge shown does not output a signal from the first level probe 22, it indicates that the condensate has not submerged the first level probe 22, and it is determined that the real-time level of the condensate is lower than the first level. At this time, it is necessary to increase the condensate generation rate and replenish the condensate in the water collection chamber. The minimum water passage area of ​​the second water path can be increased step by step.

[0057] Specifically, a flow regulating valve can be installed in the second water circuit. When the real-time liquid level is detected to be lower than the first liquid level, the controller can gradually increase the current opening of the flow regulating valve until the liquid level of the condensate rises.

[0058] In one embodiment, when using Figure 5 When the level gauge with the liquid level probe structure shown detects the real-time liquid level, if the first liquid level probe 22 outputs a liquid level signal within a preset time after the minimum water passage area of ​​the second water path is increased, it indicates that the condensate has submerged the first liquid level probe 22. Then it is determined that the liquid level of the condensate has risen, and the minimum water passage area of ​​the second water path remains unchanged. Otherwise, if it is determined that the liquid level has not risen, the minimum water passage area of ​​the second water path is increased.

[0059] In one embodiment, if the minimum water passage area of ​​the second water passage is increased to the preset maximum area, that is, the flow regulating valve is adjusted to the maximum opening, and the liquid level of the condensate still does not rise, then the water collection chamber is judged to be leaking.

[0060] S704. When the second liquid level probe outputs a signal, if it is determined that the real-time liquid level is higher than the second liquid level, the minimum water passage area of ​​the second water channel is gradually reduced until the liquid level of the condensate is reduced.

[0061] In one embodiment, if such as Figure 5 When the level gauge shown outputs a signal from the second level probe 23, it indicates that the condensate has submerged the second level probe 23, confirming that the real-time level is higher than the second level. It is necessary to reduce the rate of condensate generation or stop the generation of condensate. The minimum water passage area of ​​the second water channel can be gradually reduced.

[0062] Specifically, a flow regulating valve can be installed in the second water circuit. When the real-time liquid level is detected to be higher than the second liquid level, the flow regulating valve is controlled to gradually reduce its current opening until the liquid level of the condensate is reduced.

[0063] In one embodiment, when using Figure 5 When the level gauge with the liquid level probe structure shown detects the real-time liquid level, if the second liquid level probe 23 does not output a liquid level signal within a preset time after the minimum water passage area of ​​the second water path is reduced, it indicates that the condensate water has not submerged the second liquid level probe 23. In this case, it is determined that the liquid level of the condensate water has decreased, and the minimum water passage area of ​​the second water path remains unchanged. Otherwise, if it is determined that the liquid level has not decreased, the minimum water passage area of ​​the second water path is further reduced.

[0064] In one embodiment, if the minimum water flow area of ​​the second water path is reduced to 0, i.e. the flow regulating valve is adjusted to the minimum opening, and the condensate level still does not drop, then a whole-machine malfunction will be reported after the water usage ends.

[0065] In this embodiment, after the atomizer malfunctions, the gas water heater controls the opening of the first water circuit and continuously adjusts the minimum water flow area of ​​the second water circuit to maintain a dynamic balance between the amount of condensate generated and the amount of condensate evaporation. This allows the condenser heat exchanger to continue working, recovering heat from the flue gas and generating condensate. This reduces the risk of the water heater shutting down due to excessive condensate in case of atomizer malfunction, and the risk of the water collection chamber being deformed and damaged by heat in the high-temperature flue gas environment when there is too little condensate, thus improving the safety performance of the gas water heater.

[0066] Example 4 Figure 8 A flowchart of a control method for a gas water heater provided in Embodiment 4 of the present invention is shown below. Figure 8 As shown, the control method of this gas water heater includes: S801. After the gas water heater is working, obtain the real-time liquid level of condensate in the water collection chamber.

[0067] In one embodiment, such as Figure 6The schematic diagram of the guide rod type float level device shown illustrates the real-time level detection of condensate in the water collection chamber. The device includes a guide rod 25 disposed within the water collection chamber 21, and a second signal triggering component 27 and a first signal triggering component 26 arranged sequentially from top to bottom on the guide rod 25. It also includes a float 28 that slides up and down the guide rod 25 as the liquid level rises and falls. When the float 28 floats up and down with the liquid level, passing the second signal triggering component 27 and the first signal triggering component 26, it outputs level signals indicating the second and first liquid levels, respectively. Each level sensor can be an electromagnetic induction switch or a mechanical switch. The float 28 has a magnet or a triggering structure that activates the mechanical switch. When the float 28 rises or falls with the liquid level, passing the level sensor, the corresponding level sensor outputs a level signal indicating the corresponding liquid level.

[0068] The above example using a float illustrates the principle of real-time condensate level detection in the water collection chamber. In practical applications, those skilled in the art can also use other methods to detect the real-time condensate level.

[0069] S802. After an atomizer malfunctions, the first water circuit is opened.

[0070] The method for controlling the opening of the first water circuit after an atomizer malfunction can be referred to S102 in Embodiment 1, and will not be described in detail here.

[0071] S803. When the real-time liquid level is at the first liquid level, adjust the minimum water flow area of ​​the second water channel to the first minimum water flow area.

[0072] In one embodiment, if such as Figure 6 The guide rod type float level device shown in the figure will output a level signal indicating the first liquid level when the float 28 floats up and down with the liquid surface and reaches the first signal triggering component 26, thus confirming that the real-time liquid level of the condensate is at the first liquid level. At this time, it is necessary to increase the condensate generation rate and replenish the condensate in the water collection chamber, which can raise the minimum water passage area of ​​the second water passage to the first minimum water passage area.

[0073] S804. When the real-time liquid level is at the second liquid level, adjust the minimum water passage area of ​​the second water passage to the second minimum water passage area.

[0074] In one embodiment, if such as Figure 6 The guide rod type float level device shown in the figure will output a level signal indicating the second liquid level when the float 28 floats up and down with the liquid surface and reaches the second signal triggering component 27, thus confirming that the real-time liquid level of the condensate is at the second liquid level. At this time, it is necessary to reduce the generation rate of the condensate or stop the generation of condensate. The minimum water passage area of ​​the second water passage can be reduced to the second minimum water passage area.

[0075] By closing the second water passage or reducing the minimum water flow area of ​​the second water passage, the condenser heat exchanger can stop producing condensate or reduce the amount of condensate generated. When the amount of condensate generated is less than the amount of evaporation, the condensate level tends to drop, allowing the condensate level to drop rapidly below the second level.

[0076] Example 5 Figure 2 This is a schematic diagram of the structure of a gas water heater provided in Embodiment 5 of the present invention. Figure 2 As shown, the gas water heater includes a main heat exchanger 1, a condensing heat exchanger 2, a main inlet pipe 3, an atomizer 4, a water circuit switching component 5, and a controller 6. The water circuit switching component 5 is communicatively connected to the controller 6. The condensing heat exchanger 2 has a water collection chamber 21 for collecting the condensate produced by the condensing heat exchanger 2. The atomizer 4 is used to atomize the condensate. The water circuit switching component 5 includes a first water circuit and a second water circuit. The first water circuit is used to directly connect the main inlet pipe 3 to the main heat exchanger 1. The second water circuit is used to sequentially connect the main inlet pipe 3, the condensing heat exchanger 2, and the main heat exchanger 1. The controller is used to execute the control method of the gas water heater in any of the embodiments of Example 1 to Example 4.

[0077] like Figure 2 As shown, in an optional embodiment, the water circuit switching component 5 includes a first pipe 52, a second pipe 53, a third pipe 54, and a water circuit switching valve 51. The water circuit switching valve 51 is connected to the main water inlet pipe 3 and is communicatively connected to the controller 6. The first pipe 52 is connected to the inlet of the condensing heat exchanger 2 and the water circuit switching valve 51. The second pipe 53 is connected to the outlet of the condensing heat exchanger 2 and the inlet of the main heat exchanger 1. That is, the first pipe 52, the condensing heat exchanger 2, and the second pipe 53 are connected in sequence to form the second water circuit. The third pipe 54 is connected to the water circuit switching valve 51 and the inlet of the main heat exchanger 1 to form the first water circuit. The controller 6 can control the water circuit switching valve 51 to realize the closing and opening of the first water circuit and the second water circuit. The water circuit switching valve 51 can be one of a three-way valve, a multi-position solenoid valve, or a proportional valve.

[0078] Of course, gas water heaters can also include various types of level gauges, such as... Figure 5 The liquid level probe type liquid level gauge shown, such as Figure 6 The guide rod type float level device is shown.

[0079] Controller 6 can be a variety of general-purpose and / or dedicated processing components with processing and computing capabilities. Some examples of controller 6 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various dedicated artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, digital signal processors (DSPs), and any suitable processor, microcontroller, etc. Controller 6 performs the various methods and processes described above, such as the control methods for a gas water heater.

[0080] In some embodiments, the control method for the gas water heater may be implemented as a computer program tangibly contained in a computer-readable storage medium, which, when loaded and executed by the controller 6, can perform one or more steps of the control method for the gas water heater described above. Alternatively, in other embodiments, the controller 6 may be configured to perform the control method for the gas water heater by any other suitable means (e.g., by means of firmware).

[0081] In this embodiment, when the atomizer malfunctions, the gas water heater controls the opening of the first water circuit and adjusts the minimum water passage area of ​​the second water circuit based on the real-time liquid level. The minimum water passage area is negatively correlated with the real-time liquid level. Since high-temperature flue gas also evaporates condensate, the amount of condensate generated and evaporated fluctuates in real time. However, by continuously adjusting the minimum water passage area of ​​the second water circuit, a dynamic balance is maintained between the two. Even with atomizer malfunction, the condensate level can be controlled within a safe range, allowing the condenser heat exchanger to continue operating, recovering heat from the flue gas and generating condensate. This reduces the risk of shutdown due to excessive condensate during atomizer malfunction and damage to the water collection chamber due to heat deformation in the high-temperature flue gas environment when there is insufficient condensate, thus improving the safety performance of the gas water heater.

[0082] It should be understood that the various forms of processes shown above can be used to reorder, add, or delete steps. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this invention does not impose any limitations on them.

[0083] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A control method for a gas water heater, characterized in that, The gas water heater includes a main heat exchanger (1), a condenser heat exchanger (2), a main inlet pipe (3), an atomizer (4), and a water circuit switching assembly (5). The condenser heat exchanger (2) has a water collection chamber (21) for collecting the condensate produced by the condenser heat exchanger (2). The atomizer (4) is used to atomize the condensate. The water circuit switching assembly (5) includes a first water circuit and a second water circuit. The first water circuit is used to directly connect the main inlet pipe (3) to the main heat exchanger (1). The second water circuit is used to sequentially connect the main inlet pipe (3), the condenser heat exchanger (2), and the main heat exchanger (1). The control method includes: After the gas water heater is in operation, the real-time liquid level of the condensate in the water collection chamber is obtained; After the atomizer malfunctions, the first water path is opened, and the minimum water flow area of ​​the second water path is adjusted based on the real-time liquid level to keep the real-time liquid level within a safe range. The gas water heater further includes a first liquid level probe and a second liquid level probe. The first liquid level probe is used to detect a first liquid level, and the second liquid level probe is used to detect a second liquid level. The first liquid level is lower than the second liquid level, and the first and second liquid levels are within the safe range. Adjusting the minimum water passage area of ​​the second water path based on the real-time liquid level includes: When the first liquid level probe does not output a signal, it is determined that the real-time liquid level is lower than the first liquid level. The minimum water passage area of ​​the second water path is adjusted to the first minimum water passage area so that the condensate generation rate is greater than the evaporation rate of the condensate by the flue gas. When the second liquid level probe outputs a signal, it is determined that the real-time liquid level is higher than the second liquid level. The minimum water passage area of ​​the second water path is adjusted to the second minimum water passage area so that the condensate generation rate is less than the evaporation rate of the condensate by the flue gas. The first minimum water passage area is greater than the second minimum water passage area.

2. The control method according to claim 1, characterized in that, The atomizer determines whether it is malfunctioning based on the following methods: Acquire the current signal value of the atomizer when it is working; When the deviation between the current signal value and the preset current signal value is greater than a preset threshold, the atomizer is determined to be faulty; or, The rate of increase in the liquid level in the water collection chamber is obtained when the atomizer is working; When the liquid level increase rate is greater than the preset increase rate, the atomizer is determined to be faulty.

3. The control method according to claim 1, characterized in that, The second water passage includes a flow regulating valve, which adjusts the minimum water passage area of ​​the second water passage to a first minimum water passage area, including: Determine the first target opening degree corresponding to the first minimum water passage area; Increase the flow regulating valve from its current opening to the first target opening.

4. The control method according to claim 1, characterized in that, The second water passage includes a flow regulating valve, which adjusts the minimum water passage area of ​​the second water passage to a second minimum water passage area, including: Determine the second target opening degree corresponding to the second minimum water passage area; Reduce the flow regulating valve from its current opening to the second target opening.

5. A control method for a gas water heater, characterized in that, The gas water heater includes a main heat exchanger (1), a condenser heat exchanger (2), a main inlet pipe (3), an atomizer (4), and a water circuit switching assembly (5). The condenser heat exchanger (2) has a water collection chamber (21) for collecting the condensate produced by the condenser heat exchanger (2). The atomizer (4) is used to atomize the condensate. The water circuit switching assembly (5) includes a first water circuit and a second water circuit. The first water circuit is used to directly connect the main inlet pipe (3) to the main heat exchanger (1). The second water circuit is used to sequentially connect the main inlet pipe (3), the condenser heat exchanger (2), and the main heat exchanger (1). The control method includes: After the gas water heater is in operation, the real-time liquid level of the condensate in the water collection chamber is obtained; After the atomizer malfunctions, the first water path is opened, and the minimum water flow area of ​​the second water path is adjusted based on the real-time liquid level to keep the real-time liquid level within a safe range. The gas water heater further includes a first liquid level probe and a second liquid level probe. The first liquid level probe is used to detect a first liquid level, and the second liquid level probe is used to detect a second liquid level. The first liquid level is lower than the second liquid level, and the first and second liquid levels are within the safe range. Adjusting the minimum water passage area of ​​the second water path based on the real-time liquid level includes: If the real-time liquid level is determined to be lower than the first liquid level when the first liquid level probe does not output a signal, the minimum water passage area of ​​the second water path is gradually increased until the liquid level of the condensate rises.

6. The control method according to claim 5, characterized in that, The atomizer determines whether it is malfunctioning based on the following methods: Acquire the current signal value of the atomizer when it is working; When the deviation between the current signal value and the preset current signal value is greater than a preset threshold, the atomizer is determined to be faulty; or, The rate of increase in liquid level in the water collection chamber is obtained when the atomizer is working; When the liquid level increase rate is greater than the preset increase rate, the atomizer is determined to be faulty.

7. The control method according to claim 5, characterized in that, The method for determining the rise in the condensate level is as follows: If the first level probe outputs a level signal within a preset time period after the minimum water flow area of ​​the second water channel is increased, it is determined that the level of the condensate has risen.

8. A control method for a gas water heater, characterized in that, The gas water heater includes a main heat exchanger (1), a condenser heat exchanger (2), a main inlet pipe (3), an atomizer (4), and a water circuit switching assembly (5). The condenser heat exchanger (2) has a water collection chamber (21) for collecting the condensate produced by the condenser heat exchanger (2). The atomizer (4) is used to atomize the condensate. The water circuit switching assembly (5) includes a first water circuit and a second water circuit. The first water circuit is used to directly connect the main inlet pipe (3) to the main heat exchanger (1). The second water circuit is used to sequentially connect the main inlet pipe (3), the condenser heat exchanger (2), and the main heat exchanger (1). The control method includes: After the gas water heater is in operation, the real-time liquid level of the condensate in the water collection chamber is obtained; After the atomizer malfunctions, the first water path is opened, and the minimum water flow area of ​​the second water path is adjusted based on the real-time liquid level to keep the real-time liquid level within a safe range. The gas water heater further includes a first liquid level probe and a second liquid level probe. The first liquid level probe is used to detect a first liquid level, and the second liquid level probe is used to detect a second liquid level. The first liquid level is lower than the second liquid level, and the first and second liquid levels are within the safe range. Adjusting the minimum water passage area of ​​the second water path based on the real-time liquid level includes: When the second liquid level probe outputs a signal, if it is determined that the real-time liquid level is higher than the second liquid level, the minimum water flow area of ​​the second water path is gradually reduced until the liquid level of the condensate is reduced.

9. The control method according to claim 8, characterized in that, The atomizer determines whether it is malfunctioning based on the following methods: Acquire the current signal value of the atomizer when it is working; When the deviation between the current signal value and the preset current signal value is greater than a preset threshold, the atomizer is determined to be faulty; or, The rate of increase in the liquid level in the water collection chamber is obtained when the atomizer is working; When the liquid level increase rate is greater than the preset increase rate, the atomizer is determined to be faulty.

10. The control method according to claim 8, characterized in that, The method for determining the decrease in the condensate level is as follows: If the second level probe does not output a level signal within a preset time period after the minimum water flow area of ​​the second water channel is reduced, it is determined that the level of the condensate has decreased.

11. A control method for a gas water heater, characterized in that, The gas water heater includes a main heat exchanger (1), a condenser heat exchanger (2), a main inlet pipe (3), an atomizer (4), and a water circuit switching assembly (5). The condenser heat exchanger (2) has a water collection chamber (21) for collecting the condensate produced by the condenser heat exchanger (2). The atomizer (4) is used to atomize the condensate. The water circuit switching assembly (5) includes a first water circuit and a second water circuit. The first water circuit is used to directly connect the main inlet pipe (3) to the main heat exchanger (1). The second water circuit is used to sequentially connect the main inlet pipe (3), the condenser heat exchanger (2), and the main heat exchanger (1). The control method includes: After the gas water heater is in operation, the real-time liquid level of the condensate in the water collection chamber is obtained; After the atomizer malfunctions, the first water path is opened, and the minimum water flow area of ​​the second water path is adjusted based on the real-time liquid level to keep the real-time liquid level within a safe range. The adjustment of the minimum water passage area of ​​the second water channel based on the real-time liquid level includes: When the real-time liquid level is at the first liquid level, the minimum water passage area of ​​the second water passage is adjusted to the first minimum water passage area so that the generation rate of the condensate is greater than the evaporation rate of the condensate by the flue gas. When the real-time liquid level is at the second liquid level, the minimum water passage area of ​​the second water path is adjusted to the second minimum water passage area; wherein, the first liquid level is lower than the second liquid level, the first liquid level and the second liquid level are within the safe range, and the first minimum water passage area is greater than the second minimum water passage area, so that the condensate generation rate is less than the evaporation rate of the condensate by the flue gas.

12. The control method according to claim 11, characterized in that, The atomizer determines whether it is malfunctioning based on the following methods: Acquire the current signal value of the atomizer when it is working; When the deviation between the current signal value and the preset current signal value is greater than a preset threshold, the atomizer is determined to be faulty; or, The rate of increase in the liquid level in the water collection chamber is obtained when the atomizer is working; When the liquid level increase rate is greater than the preset increase rate, the atomizer is determined to be faulty.

13. The control method according to claim 11, characterized in that, The gas water heater also includes a guide rod type float level device for detecting the real-time liquid level. The guide rod type float level device includes a guide rod (25), a float (28) passing through the guide rod (25), and a first signal triggering component (26) and a second signal triggering component (27) located on the guide rod (25). The first signal triggering component (26) is at the same height as the first liquid level, and the second signal triggering component (27) is at the same height as the second liquid level.

14. A gas-fired water heater, characterized in that, The device includes a main heat exchanger (1), a condenser heat exchanger (2), a main inlet pipe (3), an atomizer (4), a water circuit switching assembly (5), and a controller (6). The water circuit switching assembly (5) is communicatively connected to the controller (6). The condenser heat exchanger (2) has a water collection chamber (21) for collecting the condensate generated by the condenser heat exchanger (2). The atomizer (4) is used to atomize the condensate. The water circuit switching assembly (5) includes a first water circuit and a second water circuit. The first water circuit is used to directly connect the main inlet pipe (3) to the main heat exchanger (1). The second water circuit is used to sequentially connect the main inlet pipe (3), the condenser heat exchanger (2), and the main heat exchanger (1). The controller is used to execute the control method of the gas water heater according to any one of claims 1-13.

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