Secondary heat exchange device for gas water heater and gas water heater

Abstract

The utility model provides a kind of secondary heat exchange device and gas water heater for gas water heater, including heat exchanger shell, be located in the heat exchanger shell and heat exchange coil subassembly, located the atomizer group of heat exchanger shell bottom;The heat exchange coil subassembly is used to collect the condensate water generated by heat exchange coil subassembly;The atomizer subassembly is set as when water level reaches set height, the atomizer subassembly starts and atomizes condensate water.By integrating atomizer subassembly in heat exchanger shell, condensate water generated in heat exchange process can be automatically collected and atomized inside the device, without additional external drain line.The structure hides condensate water discharge process inside the whole machine, and the atomized water vapor is naturally discharged by means of flue gas flow, thereby simplifying the installation structure, improving the overall appearance of product and user experience.

Description

Technical Field

[0001] This utility model relates to the field of water heaters, and in particular to a two-stage heat exchange device for a gas water heater and a gas water heater. Background Technology

[0002] Currently, most energy-efficient gas water heaters on the market use condensing heat exchange technology. However, these water heaters have also revealed some structural and user experience issues in practical applications.

[0003] First, as the flue gas temperature drops below the dew point during the secondary heat exchange process, a large amount of condensate will be generated on the inner wall of the heat exchanger. This condensate is usually weakly acidic, and if not handled properly, it can easily corrode metal components. Traditional solutions often use a dedicated drain pipe at the bottom of the unit to directly discharge the condensate to a floor drain or drainage system. This external drainage structure not only disrupts the overall appearance of the product but also increases installation complexity—users need to ensure that the drain pipe is unobstructed, freeze-proof, and prevents backflow of odors. Furthermore, its applicability is limited by the installation environment (such as areas without floor drains).

[0004] Secondly, most existing secondary heat exchangers adopt a single-channel or simple coil structure, with high flue gas velocity and short residence time, resulting in insufficient waste heat recovery. At the same time, condensate drainage relies on gravity flow and is prone to accumulate at the bottom of the shell. If it is not drained in time, it may cause water backflow, aggravated corrosion, or even affect combustion safety.

[0005] Therefore, there is an urgent need for a two-stage heat exchanger that can efficiently recover waste heat from flue gas and achieve green, concealed, and automatic discharge of condensate. Utility Model Content

[0006] The technical problem to be solved by this utility model is to overcome the defects of the prior art, such as the difficulty in condensate treatment and the insufficient recovery of waste heat in the secondary heat exchange, and to provide a secondary heat exchange device for gas water heaters and a gas water heater.

[0007] The present invention solves the above-mentioned technical problems through the following technical solution:

[0008] A two-stage heat exchange device for a gas water heater includes a heat exchanger shell, a heat exchange coil assembly disposed within the heat exchanger shell, and an atomizer assembly located at the bottom of the heat exchanger shell.

[0009] The atomizer assembly is used to collect the condensate generated by the heat exchange coil assembly.

[0010] The atomizer assembly is configured to activate and atomize the condensate when the water level reaches a set height.

[0011] In this solution, the aforementioned structure integrates an atomizer assembly within the heat exchanger housing, enabling the condensate generated during heat exchange to be automatically collected and atomized within the device, eliminating the need for external drainage pipes. This structure conceals the condensate discharge process within the entire unit, allowing the atomized water vapor to be naturally discharged via flue gas flow, thereby simplifying the installation structure and improving the overall product appearance and user experience.

[0012] Preferably, the heat exchange coil assembly includes multiple layers of small corrugated tubes arranged in parallel, all of which share a common inlet and outlet, so that water flows into each layer of small corrugated tubes simultaneously.

[0013] In this design, the aforementioned structure employs a multi-layered, parallel corrugated pipe system with shared inlet and outlet ports. This allows water to enter each layer of pipe simultaneously, avoiding the problem of progressively decreasing water flow caused by series connection. This layout effectively reduces overall flow resistance, improves the uniformity of water supply to each heat exchanger section, and provides a hydraulic foundation for stable heat exchange.

[0014] Preferably, the small corrugated tubes are arranged in a stacked manner.

[0015] In this scheme, the aforementioned structure is adopted, with stacked small corrugated tubes arranged closely within a limited space, reducing the gaps between the tubes and forcing the flue gas to follow a more tortuous path as it flows through the heat exchange area. This structure prolongs the contact time between the flue gas and the heat exchange tube wall, enhances the heat exchange efficiency, and helps to fully recover the waste heat from the flue gas.

[0016] Preferably, the heat exchanger shell is provided with a flue gas flow channel, the flue gas flow channel includes a flue gas inlet and a flue gas outlet, and the heat exchange coil assembly is disposed in the flue gas flow channel.

[0017] In this design, the aforementioned structure effectively constrains the flue gas flow direction by creating a clearly defined flue gas flow channel within the heat exchanger shell and placing the heat exchange coil assembly within this channel, preventing short-circuiting or bypassing. The flue gas must flow through the heat exchange coil to be discharged, thereby increasing flow resistance and residence time, and improving heat transfer efficiency.

[0018] Preferably, the flue gas outlet position of the flue gas passage forms an end guide portion, which is used to guide the flue gas to the atomization area above the atomizer assembly.

[0019] In this design, the aforementioned structure incorporates a downward-extending guide section at the end of the flue gas flow path, which actively guides the high-temperature flue gas flow towards the atomization area above the atomizer assembly. This design not only optimizes the flue gas path but also directly utilizes the waste heat of the flue gas to assist in the atomization process of condensate, accelerating water mist generation and diffusion, and preventing condensate from accumulating at the bottom.

[0020] Preferably, the atomizer assembly includes a water level float, an atomizing nozzle, and a drive motor. The water level float is located at the bottom of the heat exchanger housing and is used to detect the condensate water level. When the water level rises to a preset height, the drive motor is triggered to drive the atomizing nozzle to work and atomize the condensate water.

[0021] In this solution, the aforementioned structure is adopted, using a water level float to monitor the condensate level at the bottom of the casing in real time. When the preset height is reached, the atomization action is automatically triggered, achieving intelligent control logic with on-demand activation. This mechanism avoids continuous idling or ineffective operation of the atomizer, saving energy, extending equipment lifespan, and ensuring timely condensate treatment.

[0022] Preferably, the heat exchanger housing further includes a flue for discharging flue gas, and the atomizing area is connected to the flue so that the atomized water mist can be discharged with the flue gas.

[0023] In this design, the aforementioned structure directly connects the atomization area to the flue, allowing the fine water mist generated by atomization to be carried away by the main exhaust airflow without the need for an additional independent exhaust fan or duct. This design fully utilizes the existing exhaust power system of the gas water heater, achieving integrated condensate drainage and exhaust gas discharge, resulting in a simple structure and low energy consumption.

[0024] Preferably, the atomizer assembly includes a neutralization device that eliminates acidic components in the condensate by using a built-in neutralizing agent or by adding a neutralizing liquid externally.

[0025] In this solution, the aforementioned structure addresses the issue that the condensate produced by gas combustion is typically weakly acidic, and direct discharge could corrode metal components or pollute the environment. By neutralizing the condensate before atomization (e.g., by using a built-in neutralizing agent or adding an external neutralizing liquid), its acidic components can be effectively removed, improving the device's durability and environmental compliance, thus meeting the requirements for green home appliances.

[0026] Preferably, the bottom of the flue gas passage is provided with an inclined bottom surface, which is inclined toward the atomizer assembly and extends downward so that condensate water can quickly collect in the atomizer assembly.

[0027] In this design, the aforementioned structure features a bottom surface that slopes towards the atomizer assembly at the bottom of the flue gas flow channel. Gravity allows condensate to flow naturally to the collection area. This structure prevents condensate from stagnating in certain areas, reducing the risk of corrosion or blockage caused by water accumulation. It also accelerates water collection, ensuring timely response from the atomizer.

[0028] A gas water heater includes a combustion chamber, a primary heat exchange device, and a secondary heat exchange device for a gas water heater as described above; the secondary heat exchange device is connected downstream of the primary heat exchange device and receives high-temperature flue gas from the primary heat exchange device.

[0029] In this solution, the aforementioned structure integrates the secondary heat exchanger with condensate atomization and discharge function into the overall gas water heater system. This makes it a key component of the Level 1 energy efficiency product, not only efficiently recovering waste heat from flue gas to improve the overall energy efficiency rating, but also completely resolving the installation pain point of traditional models requiring external drain pipes. This integrated solution balances thermal efficiency, aesthetic appeal, and user convenience, significantly enhancing the product's market competitiveness.

[0030] The significant advantages of this invention are: by integrating an atomizer assembly within the heat exchanger housing, the condensate generated during heat exchange can be automatically collected and atomized inside the device, eliminating the need for external drainage pipes. This structure conceals the condensate discharge process within the entire unit and allows the atomized water vapor to be naturally discharged via flue gas flow, thereby simplifying the installation structure and improving the overall appearance and user experience of the product. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the internal structure of the two-stage heat exchange device according to an embodiment of the present invention.

[0032] Figure 2 This is a schematic diagram of the internal structure of the two-stage heat exchange device according to an embodiment of the present invention.

[0033] Figure 3 This is a schematic diagram of the structure of the two-stage heat exchange device according to an embodiment of the present invention.

[0034] Figure 4 This is a schematic diagram of the structure of the secondary flue gas flow channel according to an embodiment of the present invention.

[0035] Figure 5 This is a schematic diagram of the structure of the secondary heat exchange coil assembly according to an embodiment of the present invention.

[0036] Figure 6 This is a schematic diagram of the structure of the two-stage heat exchange device according to an embodiment of the present invention.

[0037] Figure 7 This is a schematic diagram of the structure of the two-stage heat exchange device according to an embodiment of the present invention.

[0038] Explanation of reference numerals in the attached figures:

[0039] Heat exchanger shell 10

[0040] Heat exchanger coil assembly 20

[0041] Atomizer assembly 30

[0042] Water level float 31

[0043] Neutralization treatment device 32

[0044] Smoke flow channel 40

[0045] Sloping bottom 41

[0046] End guide section 42

[0047] flue gas inlet 43

[0048] Flue gas outlet 44

[0049] Smoke baffle 50

[0050] 60 inlet / outlet water connector

[0051] Inlet 61

[0052] Outlet 62

[0053] Atomization area 70

[0054] Gas collection hood 80

[0055] 90 flue Detailed Implementation

[0056] The present invention will be described more clearly and completely below with reference to the accompanying drawings, using a preferred embodiment.

[0057] The number of small corrugated tubes is six layers, and the six layers of small corrugated tubes are arranged sequentially along the flue gas flow direction to form a serpentine flow channel structure.

[0058] like Figures 1 to 7 As shown, this utility model provides a two-stage heat exchange device for a gas water heater. The core of this device lies in integrating an atomization function within the heat exchanger housing 10, achieving green and concealed discharge of condensate. Specifically, the two-stage heat exchange device includes a heat exchanger housing 10, a heat exchange coil assembly 20 disposed within the heat exchanger housing 10, and an atomizer assembly 30 located at the bottom of the heat exchanger housing 10. During the operation of the gas water heater, high-temperature flue gas flows through the heat exchange coil assembly 20 for heat exchange, producing condensate. This condensate naturally drips and collects at the bottom of the heat exchanger housing 10, where it is collected by the atomizer assembly 30. When the collected condensate level reaches a preset height, the atomizer assembly 30 is automatically activated, atomizing the condensate into fine water mist. This design cleverly integrates the condensate treatment process entirely within the entire unit, eliminating the need for external drainage pipes. This not only simplifies the installation process but also greatly enhances the overall appearance of the product and the user experience.

[0059] Furthermore, such as Figure 2 , Figure 5 As shown, to optimize water flow distribution and improve heat exchange efficiency, the heat exchange coil assembly 20 adopts a multi-layered, parallel corrugated pipe structure. All corrugated pipes share the same inlet 61 and outlet 62, i.e., they share the same inlet and outlet connectors 60, allowing domestic water to flow into each layer of corrugated pipes simultaneously and evenly. This parallel design effectively avoids the problem of insufficient heat exchange at the end caused by the gradual attenuation of water flow in traditional series structures, significantly reduces the resistance of the entire water flow path, ensures the uniformity of water supply to each heat exchange pipe section, and provides a good hydraulic foundation for stable and efficient heat exchange.

[0060] like Figure 5 As shown, based on this, the small corrugated tubes are arranged in a stacked manner within the shell. This close arrangement minimizes the gaps between the tubes, creating a more complex flue gas passage within the limited shell space. When the flue gas flows through this area, its flow path is forced to become more tortuous, thereby extending the effective contact time and contact area between the flue gas and the heat exchange tube walls. This structural optimization directly enhances heat exchange efficiency, helps to more fully recover waste heat from the flue gas, and macroscopically improves the overall energy efficiency performance of the unit.

[0061] like Figure 1 , Figure 4 As shown, to ensure efficient and orderly flow of flue gas through the heat exchange area, a clearly defined flue gas flow channel 40 is provided within the heat exchanger shell 10. This flue gas flow channel 40 has a clearly defined flue gas inlet 43 and flue gas outlet 44, and the heat exchange coil assembly 20 is precisely positioned within this flue gas flow channel 40. By constructing such a controlled flow channel, the flow direction of the flue gas can be effectively constrained, preventing short-circuiting or bypassing. The flue gas must flow completely through the heat exchange coil assembly 20 before being discharged from the flue gas outlet 44. This process increases the flow resistance and residence time of the flue gas, thereby significantly improving the efficiency of heat transfer.

[0062] In this embodiment, a baffle 50 is also provided around the flue gas flow channel 40, which blocks the outer side of the flue gas flow channel 40 from the middle, so that the flue gas can only pass through the flue gas inlet 43 and the flue gas outlet 44 of the flue gas flow channel 40. In addition, the heat exchanger shell 10 is also provided with a gas collecting hood 80, through which the flue gas enters the interior of the heat exchanger shell 10.

[0063] Furthermore, such as Figure 1 , Figure 4As shown, to coordinate the treatment of condensate and optimize flue gas energy utilization, a terminal guide section 42 is formed at the flue gas outlet 44 of the flue gas passage 40. This terminal guide section 42 extends downwards, and its main function is to actively guide the high-temperature flue gas about to be discharged to the atomization area 70 above the atomizer assembly 30. This design not only optimizes the final flow direction of the flue gas, but more importantly, it directly uses the waste heat carried by the flue gas to assist the atomization process of the condensate. The high-temperature flue gas flowing through the atomization area 70 accelerates the generation and diffusion of water mist, effectively preventing condensate from accumulating at the bottom of the housing, ensuring the high efficiency and timeliness of the atomization process.

[0064] Regarding the specific structure of the atomizer assembly 30, it integrates a water level float 31, an atomizing nozzle, and a drive motor. The water level float 31 is located at the bottom of the heat exchanger housing 10 and can monitor the water level changes of the condensate in real time. When the water level rises to a preset height as the condensate accumulates, the water level float 31 triggers a control signal, activating the drive motor, which in turn drives the atomizing nozzle to atomize the condensate. This intelligent start-stop control logic based on water level ensures that the atomizer only operates when needed, avoiding energy waste and equipment damage caused by continuous idling. This saves energy, extends the service life of the equipment, and ensures that the condensate is treated promptly.

[0065] like Figure 1 As shown, to ensure smooth discharge of atomized water vapor, the heat exchanger shell 10 also includes a flue 90 for exhausting flue gas. Crucially, the aforementioned atomization area 70 is interconnected with this flue 90. This allows the fine water mist generated by the atomizing nozzles to directly enter the flue 90 and merge with the main exhaust gas flow. Utilizing the existing exhaust power of the gas water heater's core fan, this water mist can be carried away and discharged outdoors along with the exhaust gas. This design fully utilizes the system's existing power resources, eliminating the need for additional independent exhaust fans or pipes, achieving integrated condensate drainage and exhaust gas discharge, resulting in a simple structure and extremely low energy consumption.

[0066] Considering that condensate is typically weakly acidic and may corrode metal components or pose environmental hazards, a neutralization device 32 is integrated into the atomizer assembly 30. This neutralization device 32 can effectively neutralize the acidic components of the condensate before it is atomized, either by using a built-in solid neutralizing agent or by injecting neutralizing liquid through an external inlet. This measure significantly improves the corrosion resistance of the device's internal components, ensuring long-term reliable operation of the product while also meeting green and environmentally friendly emission requirements.

[0067] Furthermore, to accelerate the collection of condensate and improve the atomization response speed, the bottom of the flue gas flow channel 40 is provided with an inclined bottom surface 41. This inclined bottom surface 41 slopes downwards towards the atomizer assembly 30. Under the action of gravity, the condensate generated during the heat exchange process flows rapidly along this inclined surface to the collection area of ​​the atomizer assembly 30. This structural design effectively avoids the retention of condensate in local areas of the flow channel, reducing not only the risk of corrosion and blockage caused by water accumulation, but also providing sufficient water supply for the timely and effective operation of the atomizer assembly 30.

[0068] Based on the aforementioned two-stage heat exchange device, this utility model also provides a gas water heater. This gas water heater includes a combustion chamber, a primary heat exchange device, and a secondary heat exchange device as described in any of the preceding embodiments. The secondary heat exchange device is connected downstream of the primary heat exchange device and is specifically designed to receive and further recover waste heat from the high-temperature flue gas after the primary heat exchange. By integrating the secondary heat exchange device of this utility model into the overall gas water heater system, not only can waste heat from the flue gas be efficiently recovered, significantly improving the overall energy efficiency rating of the unit, but it also completely solves the installation pain point of traditional first-level energy efficiency models requiring an external drain pipe. This integrated solution achieves an excellent balance between thermal efficiency, structural aesthetics, and user convenience, greatly enhancing the product's overall competitiveness and market adaptability.

[0069] While specific embodiments of this utility model have been described above, those skilled in the art should understand that these are merely illustrative examples, and the scope of protection of this utility model is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of this utility model, but all such changes and modifications fall within the scope of protection of this utility model.

Claims

1. A two-stage heat exchange device for a gas water heater, characterized in that, It includes a heat exchanger housing, a heat exchanger coil assembly disposed within the heat exchanger housing, and an atomizer assembly located at the bottom of the heat exchanger housing; The atomizer assembly is used to collect the condensate generated by the heat exchange coil assembly. The atomizer assembly is configured to activate and atomize the condensate when the water level reaches a set height.

2. The two-stage heat exchange device for a gas water heater according to claim 1, characterized in that, The heat exchange coil assembly includes multiple layers of small corrugated tubes arranged in parallel. All the small corrugated tubes share a common inlet and outlet, so that water flows into each layer of small corrugated tubes simultaneously.

3. The two-stage heat exchange device for a gas water heater according to claim 2, characterized in that, The small corrugated tubes are arranged in a stacked manner.

4. The two-stage heat exchange device for a gas water heater according to claim 1, characterized in that, The heat exchanger shell is provided with a flue gas flow channel, which includes a flue gas inlet and a flue gas outlet, and the heat exchange coil assembly is disposed in the flue gas flow channel.

5. The two-stage heat exchange device for a gas water heater according to claim 4, characterized in that, The flue gas outlet position of the flue gas passage forms an end guide section, which is used to guide the flue gas to the atomization area above the atomizer assembly.

6. The two-stage heat exchange device for a gas water heater according to claim 1, characterized in that, The atomizer assembly includes a water level float, an atomizing nozzle, and a drive motor. The water level float is located at the bottom of the heat exchanger housing and is used to detect the condensate water level. When the water level rises to a preset height, the drive motor is triggered to drive the atomizing nozzle to work and atomize the condensate water.

7. The two-stage heat exchange device for a gas water heater according to claim 5, characterized in that, The heat exchanger housing also includes a flue for discharging flue gas, and the atomizing area is connected to the flue so that the atomized water mist can be discharged with the flue gas.

8. The two-stage heat exchange device for a gas water heater according to claim 1, characterized in that, The atomizer assembly includes a neutralization device that eliminates acidic components in the condensate by using a built-in neutralizing agent or by adding a neutralizing liquid externally.

9. The two-stage heat exchange device for a gas water heater according to claim 4, characterized in that, The bottom of the flue gas passage is provided with an inclined bottom surface, which is inclined towards the atomizer assembly and extends downward so that condensate water can quickly collect to the atomizer assembly.

10. A gas-fired water heater, characterized in that, It includes a combustion chamber, a primary heat exchange device, and a secondary heat exchange device for a gas water heater as described in any one of claims 1 to 9; the secondary heat exchange device is connected downstream of the primary heat exchange device and receives high-temperature flue gas from the primary heat exchange device.

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