An electric water heater and an inner container outer wall heating method and a heat preservation structure of an electric faucet

Abstract

This invention discloses an inner tank outer wall heating and insulation component and its heating method for an electric water heater and electric water faucet. The component includes an inner tank, an outer shell, and an insulation component filling the space between them. A thermally conductive coating is provided on the outer wall surface of the inner tank. The insulation component consists of an annular heating element located on the inner side and an insulation layer located on the outer side, with the annular heating element covering and adhering to the thermally conductive coating. This invention reduces contact thermal resistance by filling microscopic gaps with the thermally conductive coating to form a solid thermally conductive medium; it utilizes a water pressure switch connected in series in the power supply circuit to achieve physical linkage between the water circuit and the electrical circuit; and the safety control module adjusts the power based on a PID algorithm and monitors for leakage and dry burning. This invention achieves complete separation of water and electricity, eliminating the risks of scale buildup and leakage, while also solving the problem of delayed thermal response in outer wall heating, resulting in precise temperature control and energy efficiency.

Description

Technical Field

[0001] This invention relates to the field of fluid heating equipment technology, specifically to a heating method and insulation structure for the outer wall of the inner tank of an electric water heater and an electric water faucet. Background Technology

[0002] Existing electric water heaters and faucets primarily use a built-in heating element (such as a metal heating element or a ceramic heating rod) as the core heat source. In this conventional structure, the heating element is directly immersed in the water flow inside the inner tank, and heat is transferred to the fluid through direct contact.

[0003] However, this direct-contact heating method has several technical limitations in practical applications. Because the heating element operates at high temperatures and is in direct contact with water for extended periods, calcium and magnesium ions easily precipitate and adhere to its surface, forming scale. Over time, the thickening scale layer severely hinders heat transfer, leading to a significant decrease in the heating element's thermal efficiency—sometimes exceeding 15%. Furthermore, the long-term presence of scale negatively impacts the cleanliness of the output water.

[0004] In terms of safety and maintenance, built-in heating elements typically rely on internal insulating materials such as magnesium oxide powder to achieve water and electricity isolation. Under long-term alternating hot and cold conditions and immersion in water, the insulation layer faces the risk of aging or damage, and insulation failure may lead to leakage accidents. In addition, when the heating element needs to be repaired or replaced, it often involves disassembling the inner tank, making the maintenance process rather cumbersome.

[0005] Meanwhile, the built-in heating element operates in a harsh environment, directly subjected to water flow impacts and frequent temperature fluctuations, which can easily lead to material fatigue and rapid power decay. Its actual average service life is often far shorter than the overall design life of the equipment. In terms of heating performance, since the built-in heating tube usually exists as a point or line-like local heat source, it is difficult to achieve uniform heating of the water in the inner tank, which can easily lead to significant fluctuations in the outlet water temperature.

[0006] Although alternative solutions such as electromagnetic heating or surface coating heating have emerged in the industry, electromagnetic heating technology typically faces problems such as large equipment size and high manufacturing costs; while surface coating heating technology suffers from technical bottlenecks such as unstable adhesion between the film and the substrate, easy detachment, and excessively rapid power attenuation, which limit its large-scale commercialization. Therefore, there is an urgent need for a new heating technology structure that can balance heating efficiency, safety, service life, and heating uniformity. Summary of the Invention

[0007] To address the shortcomings of existing technologies, this invention provides a heating method and insulation structure for the outer wall of the inner tank of an electric water heater and an electric water faucet. It solves the technical problems of existing built-in heating technologies, such as scale buildup caused by direct contact between the heating element and the water flow, leakage hazards caused by aging of the insulation layer, short service life of core components, high contact thermal resistance, delayed thermal response, and low accuracy of outlet water temperature control due to uneven heating.

[0008] The first aspect of the present invention provides a heat insulation structure for the outer wall of the inner tank of an electric water heater and an electric water faucet.

[0009] The structure includes an inner liner, an outer shell, and an insulation component that fills the space between the outer shell and the inner liner. The inner liner is configured as a sealed hollow cavity for storing or circulating fluids, and its outer wall surface is coated with a thermally conductive coating. The outer shell covers the outer side of the inner liner, providing mechanical support and protection.

[0010] The heat insulation component is a composite component consisting of a ring-shaped heating element and a heat insulation layer. The ring-shaped heating element is located on the inner side of the heat insulation component, directly covering and adhering to the thermally conductive coating on the outer wall of the inner liner; the heat insulation layer is located on the outer side of the heat insulation component, covering the outer surface of the ring-shaped heating element.

[0011] In this structure, a thermally conductive coating fills the microscopic gaps in the outer wall surface of the inner liner, transforming the contact interface between the inner liner wall and the annular heating element from gaseous to solid-solid thermal conductivity, thus eliminating the contact thermal resistance caused by the microscopic air gaps. The annular heating element employs a flexible heating film or a nano-alloy heating ring, utilizing its flexible physical properties to adapt to the thermal expansion and contraction deformation of the inner liner during heating, maintaining a high degree of adhesion to the outer wall of the inner liner. The insulation layer is made of high-temperature resistant fiber material, constructing an insulating boundary so that the heat flux generated by the annular heating element is mainly transferred radially inward to the inner liner, reducing heat loss towards the outer shell.

[0012] Furthermore, the component is also equipped with an electrical control system, including a water flow control component located at the inlet pipe end, a water pressure switch integrated inside or near the component, a temperature sensor located at the outlet end, and a safety control module. The water pressure switch is connected in series in the power supply circuit of the annular heating element or the drive circuit of the power drive unit. By sensing changes in fluid pressure, it directly and physically switches the circuit on and off, achieving a mechanical hard connection between the water circuit state and the electrical circuit state, ensuring forced power-off when there is no water pressure.

[0013] The second aspect of the present invention provides a heating method for the outer wall of the inner tank of an electric water heater and an electric water faucet.

[0014] This method is based on the aforementioned inner liner outer wall heating and insulation components. It manages the generation, transfer, and retention of heat energy through a phased control strategy, specifically including the following steps: During the standby monitoring phase, the safety control module monitors the leakage current data of the circuit and the wall temperature data of the inner liner in real time through a zero-sequence current transformer and a temperature probe attached to the outer wall of the inner liner. The system maintains standby mode only when the electrical insulation performance and thermophysical state are within the preset safety threshold range; otherwise, it executes physical interlocking.

[0015] During the water flow triggering phase, when the water flow control component is activated, the fluid pressure established in the inlet pipe pushes the water pressure switch to close, connecting the power supply circuit of the annular heating element. At this time, the safety control module executes a feedforward control strategy, directly outputting a preset initial power command to the annular heating element within the time window during which no temperature sensor feedback data is received. This initial power command is used to provide a high-energy-density heat input, overcoming the inherent thermal inertia of the inner liner wall and thermally conductive coating, and rapidly establishing a temperature gradient on the outer wall of the inner liner pointing towards the fluid side.

[0016] During the thermostatic adjustment phase, the system enters closed-loop control. The temperature sensor collects real-time fluid temperature data at the water outlet of the inner tank at a preset frequency. The safety control module calculates the set temperature. Difference from real-time fluid temperature To eliminate static errors and suppress dynamic overshoot, the microprocessor uses a proportional-integral-derivative (PID) algorithm to calculate the instantaneous power required at the moment. The control law is as follows: ; In the formula, This is the proportional gain coefficient, used to respond to the current deviation; This is the integral gain coefficient, used to eliminate steady-state error; This is the differential gain coefficient, used to predict the trend of deviation. For integration, the variable is [variable name]. The calculated result is [result]. The value is converted into a pulse width modulation signal or a conduction angle trigger signal, which controls the power drive unit to adjust the output of the annular heating element. Heat passes through the low thermal resistance thermally conductive coating and the inner liner wall to heat the fluid, while the outer insulation layer prevents heat loss, thus improving the system's thermal efficiency.

[0017] During a power outage, when the water pressure control component shuts down, causing the fluid pressure to disappear, the water pressure switch physically disconnects, forcibly cutting off the heating circuit. At this time, the insulation layer on the outside of the insulation component prevents the residual heat from the annular heating element and the inner tank wall from dissipating to the external environment. Instead, the residual heat is conducted unidirectionally through the thermally conductive coating to the static fluid inside the inner tank, thereby slowing down the rate of temperature drop of the fluid inside the inner tank and preventing electronic components from being affected by residual heat.

[0018] This invention provides a heating method and insulation structure for the outer wall of the inner tank of an electric water heater and an electric water faucet. It has the following beneficial effects: 1. This invention employs a structural design where a ring-shaped heating element is encased in the outer wall of a sealed inner tank, achieving complete physical isolation between the heating element and the fluid. This non-contact heating method fundamentally eliminates the scale buildup problem caused by long-term immersion in traditional immersion heating tubes, ensuring water cleanliness. Simultaneously, due to the water-electricity separation structure, the risk of leakage caused by heating tube corrosion or bursting is eliminated. Combined with an integrated leakage detection unit, this significantly improves the electrical safety and reliability of the equipment during long-term operation.

[0019] 2. This invention significantly optimizes heat transfer efficiency and temperature control accuracy by filling the space between the inner tank and the heating element with a thermally conductive coating and combining it with an outer insulation layer. The thermally conductive coating effectively fills the microscopic interface gaps, minimizing contact thermal resistance. Combined with the insulation effect of the outer insulation layer, this ensures that heat flux is primarily transferred inward, achieving a thermal efficiency that meets Level 1 energy efficiency standards (e.g., above 98%). Furthermore, by incorporating a PID algorithm for real-time adjustment of heating power, the inherent thermal inertia lag problem of external wall heating is overcome, keeping outlet water temperature fluctuations within a small range (e.g., within ±1℃), achieving rapid and stable constant temperature output.

[0020] 3. This invention utilizes the physical series logic of a water pressure switch and a power supply circuit to construct a reliable mechanical anti-dry-burning protection mechanism. The water pressure switch directly responds to changes in fluid pressure to switch on and off, ensuring that the heating power is forcibly cut off in the event of water shortage or low water pressure. Its response priority is higher than software control, effectively preventing dry-burning accidents caused by electronic component failure. Simultaneously, the 360-degree wrapping design of the annular heating element ensures uniform heating of the inner tank, avoiding thermal stress concentration caused by localized high temperatures, thereby significantly extending the service life of the inner tank and core heating components.

[0021] 4. This invention adopts a modular design for the heating element, inner tank, and electrical control system. This structural layout changes the complex assembly logic of traditional integrated water heaters, allowing the heating module and control module to be prefabricated independently and assembled in parallel, significantly optimizing the production and assembly process and improving assembly efficiency. Simultaneously, this modular design simplifies later maintenance. When a single module (such as the electrical control system or heating element) fails, there is no need to disassemble or scrap the entire unit; only the corresponding module needs to be replaced, thereby reducing the overall operation and maintenance costs and repair difficulty of the equipment. Attached Figure Description

[0022] Figure 1 This is a perspective view of the present invention; Figure 2 This is a diagram of the internal structure of the electric water heater of the present invention; Figure 3 This is a diagram of the internal structure of the electric water faucet of the present invention; Figure 4This is a schematic diagram of a partial structural connection of the electric water faucet of the present invention; Figure 5 This is a schematic diagram of a partial structural connection of the electric water heater of the present invention; Figure 6 This is a radial layer diagram showing the fit between the thermal insulation component and the inner liner of the present invention. Figure 7 This is a schematic diagram of the heating control method of the present invention; Figure 8 This is a block diagram illustrating the electrical control system principle of the present invention.

[0023] The components include: 1. Electric water heater; 2. Electric water faucet; 3. Insulation components; and 4. Inner tank. Detailed Implementation

[0024] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. 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 are within the scope of protection of the present invention.

[0025] Please see the appendix Figure 1 -Appendix Figure 8 The present invention provides a heating method and insulation structure for the outer wall of the inner tank of an electric water heater and an electric water faucet, including an electric water heater 1 or an electric water faucet 2, an insulation component 3, an inner tank 4, and an electrical control system that works in conjunction with it.

[0026] The inner tank 4 serves as a water storage and heat exchange container, located inside the electric water heater 1 or electric water faucet 2. The inner tank 4 is a sealed hollow cavity made of 304 stainless steel or ceramic. The two ends of the inner tank 4 are connected to the inlet and outlet water pipes, respectively, forming independent water flow channels. A thermally conductive coating is applied to the outer wall surface of the inner tank 4, filling the microscopic gaps on the outer wall surface and creating a heat transfer medium layer between the inner tank 4 and the insulation component 3.

[0027] The insulation component 3 is filled and disposed between the outer shell of the electric water heater 1 and the inner tank 4, or between the outer shell of the electric water faucet 2 and the inner tank 4. The insulation component 3 is composed of a ring-shaped heating element and an insulation layer. The ring-shaped heating element is located on the inner side of the insulation component 3, directly covering and adhering to the thermally conductive coating on the outer wall of the inner tank 4, with a adhesion degree greater than or equal to 95%. The insulation layer is located on the outer side of the insulation component 3, covering the outer surface of the ring-shaped heating element to form an insulating boundary. The outer shell of the electric water heater 1 or the electric water faucet 2 covers the outer side of the insulation component 3, providing mechanical support and protection for the internal components.

[0028] The electrical control section of the system includes a water flow control component, a safety control module, and a temperature sensor. The water flow control component is installed at the inlet pipe end and integrates a water pressure switch. The water pressure switch monitors changes in fluid pressure within the pipe and generates an on / off signal. The temperature sensor is located at the outlet of the inner tank 4 to collect real-time fluid temperature data.

[0029] The safety control module is electrically connected to the annular heating element, water pressure switch, and temperature sensor. Internally, the safety control module integrates a microprocessor and power regulation circuitry to receive sensor signals and adjust the electrical power supplied to the annular heating element. The annular heating element uses a flexible heating film or nano-alloy heating coil, possessing the physical characteristic of deforming with the thermal expansion and contraction of the inner liner. The insulation layer is made of aluminum silicate fiber material.

[0030] The electric water heater 1 or electric water faucet 2 adopts a highly integrated modular structure design. Specifically, the annular heating element, the insulation layer, and the inner tank 4 and its outer wall thermally conductive coating are encapsulated to form an independent heating module; the water flow control component, water pressure switch, temperature sensor, and safety control module are integrated to form an independent control module. The heating module and the control module are connected through a standardized electrical interface and quick-release mechanical clips.

[0031] This modular design changes the traditional sequential assembly logic of integrated equipment, allowing heating and control modules to be independently prefabricated and assembled in parallel on the production line. Practical verification shows that compared to traditional non-modular structures, this design improves overall assembly efficiency by approximately 50%. Furthermore, in terms of equipment maintenance, if a module (such as the electrical control section) fails, maintenance personnel do not need to disassemble or scrap the entire machine; they only need to replace the corresponding faulty module through a standardized interface. This design significantly reduces manufacturing costs and also greatly reduces the difficulty of subsequent maintenance and spare parts replacement costs for users.

[0032] During system operation, the water flow control component is activated, allowing external fluid to enter the internal cavity of the inner tank 4. The pressure generated by the fluid flow pushes the water pressure switch to close. The safety control module receives the closing signal from the water pressure switch and connects the power supply circuit of the annular heating element. The annular heating element generates Joule heat when energized, and the heat is transferred sequentially through the thermally conductive coating and the wall of the inner tank 4 to the internal fluid.

[0033] A temperature sensor monitors the outlet water temperature in real time and feeds the data back to the safety control module. Based on the difference between the set temperature and the feedback temperature, the safety control module uses a PID algorithm to adjust the output power of the annular heater. When the outlet water temperature reaches the set value, the system maintains a constant temperature output. The heat generated by the annular heater is blocked by the outer insulation layer and is mainly transferred to the inner tank in four directions.

[0034] When the water flow control component is turned off, the pressure in the inlet pipe drops. The water pressure switch resets and opens. In response to the water pressure switch's disconnect signal, the safety control module cuts off the power supply to the annular heating element, stopping heating. Residual heat within the inner tank 4 is maintained by the insulation component 3, awaiting the next startup.

[0035] The safety control module is also connected to an anti-dry-burning protection unit and a leakage current detection unit. When the inner tank 4 wall temperature exceeds a preset threshold or leakage current is detected in the circuit, the safety control module performs a power-off operation. The entire heating process is completed outside the inner tank 4, and the heating element does not have physical contact with the water flow inside the inner tank 4.

[0036] In standby mode, step S100 specifically includes the following sub-steps: Step S101: The leakage current detection unit continuously collects the residual current value in the main circuit. The leakage current detection unit uses a zero-sequence current transformer installed on the power input line to monitor the vector sum of the currents in the live wire and neutral wire in real time. When the detected residual current value... When the current is greater than or equal to the preset safety threshold (e.g., 0.15mA), the safety control module determines that there is a leakage fault and triggers the physical tripping mechanism within 0.1 seconds to cut off the main power supply of the system and lock the reset function until the fault is cleared.

[0037] In step S102, the wall temperature monitoring unit continuously reads the wall temperature of the inner liner 4 through a temperature sensor attached to the outer wall of the inner liner 4. The temperature sensor is located at the edge of the heating area of ​​the annular heating element. When the monitored wall temperature... When the temperature exceeds a preset dry-burning threshold (e.g., 95 degrees Celsius), the system determines it to be in a dry-burning or abnormal heat dissipation state, and the safety control module immediately blocks the heating output signal. For the specific temperature sensor selection and signal conditioning circuit, those skilled in the art can choose a thermistor or thermocouple in conjunction with an analog-to-digital converter circuit according to actual needs; this is well-known technology in the field and will not be elaborated upon here.

[0038] Step S103: The security control module performs a logical AND operation. Only when... Less than the safety threshold and The system can only maintain a standby ready state and allow responses to subsequent water flow trigger signals when the water level is below the dry-burning threshold; otherwise, the system remains locked and ignores any external trigger commands.

[0039] In response to the water flow start signal, step S200 specifically includes the following sub-steps: Step S201, Physical Triggering Process. When the user turns on the water flow control component at the inlet pipe end, fluid dynamic pressure is established inside the pipe. The fluid pressure acts on the sensing diaphragm of the water pressure switch, overcoming the spring resistance and pushing the microswitch to close. The water pressure switch is connected in series in the main power supply circuit or relay control circuit of the annular heating element, and its closing action directly conducts the physical connection of the hardware circuit.

[0040] Step S202, Feedforward Start-up Process. After the safety control module detects the closed level signal of the water pressure switch, it outputs a preset initial power command without waiting for feedback data from the temperature sensor. This initial power command aims to overcome the thermal inertia of the inner tank 4 wall, the thermally conductive coating, and the annular heating element, so that the outer wall of the inner tank 4 can quickly establish a temperature gradient before the fluid carries away the heat.

[0041] Entering the constant temperature regulation stage, step S300 specifically includes the following sub-steps: Step S301, Temperature Acquisition and Error Calculation. A temperature sensor installed at the water outlet of the inner tank 4 acquires the real-time water temperature at a preset sampling frequency (e.g., 10 times per second). The microprocessor inside the safety control module reads the target temperature set by the user. And calculate the current time. temperature deviation The calculation formula is: ; Step S302, PID calculation and power decision. To achieve high-precision temperature control, eliminate static errors, and suppress dynamic overshoot, the safety control module uses a proportional-integral-derivative (PID) algorithm to calculate the required control input. The instantaneous power output to the annular heating element is then determined. Follow the following control laws: ; In the formula: This represents the proportional gain coefficient, used to respond to the current temperature deviation magnitude; This represents the integral gain coefficient, used to accumulate historical deviations and eliminate steady-state errors. This represents the differential gain coefficient, used to predict the trend of temperature deviation and suppress temperature overshoot in advance. This represents the integration variable. The microprocessor calculates this... The value generates the corresponding pulse width modulation (PWM) signal or thyristor conduction angle trigger signal.

[0042] Step S303, heat transfer is implemented. The annular heating element receives modulated electrical power and generates Joule heat. The heat is first transferred to the thermally conductive coating on the outer wall surface of the inner liner 4. The thermally conductive coating fills the microscopic pits on the stainless steel or ceramic surface of the inner liner 4, converting the original air thermal conductivity (thermal conductivity approximately 0.026 W / m·K) at the contact interface into solid medium thermal conductivity (thermal conductivity greater than 200 W / m·K), significantly reducing the contact thermal resistance. The heat is then transferred through the wall of the inner liner 4 to the fluid flowing inside. During this process, the insulation layer wrapped around the annular heating element (belonging to the outer part of the insulation component 3) creates a high thermal resistance boundary, forcing the heat flux to be transferred mainly radially inward, reducing heat loss towards the outer shell.

[0043] In response to the water flow shut-off signal, step S400 specifically includes the following sub-steps: Step S401, physical disconnection process. When the water flow control component is turned off, the fluid dynamic pressure in the water inlet pipe rapidly decreases below the reset threshold. The water pressure switch disconnects under the action of the reset spring, physically cutting off the main power supply circuit of the annular heating element. This power-off action has a higher priority than the software logic of the safety control module, ensuring that heating is forcibly stopped the instant the water flow stops, preventing the stagnant fluid in the inner tank 4 from overheating and vaporizing.

[0044] Step S402, Residual Heat Management. After power failure, some heat remains in the annular heating element and the inner tank 4 wall. At this time, the outer insulation layer of the insulation component 3 prevents the heat from dissipating rapidly into the environment, allowing the residual heat to be slowly released into the water inside the inner tank 4. This thermal resistance characteristic prevents the electronic components inside the electric water heater 1 or electric water faucet 2 from overheating due to the heat immersion effect after shutdown, and also slows down the rate of temperature drop in the inner tank 4, facilitating rapid heating upon the next startup.

Claims

1. An electric water heater and electric faucet inner tank outer wall heat preservation structure, characterized in that, include: The inner liner (4) is configured as a sealed hollow cavity for storing or circulating fluid, and the outer wall surface of the inner liner (4) is provided with a thermally conductive coating. An outer shell that covers the outside of the inner liner (4); and The heat insulation component (3) is filled between the outer shell and the inner liner (4); The heat insulation component (3) is a composite component consisting of a ring-shaped heating element and a heat insulation layer; The annular heating element is located on the inner side of the heat preservation component (3), covering and adhering to the heat-conducting coating on the outer wall of the inner liner (4); The insulation layer is located on the outer side of the insulation component (3) and covers the outer surface of the annular heating element.

2. The inner tank outer wall insulation structure of an electric water heater and electric water faucet according to claim 1, characterized in that, The thermally conductive coating fills the microscopic gaps on the outer wall surface of the inner liner (4) and forms a solid thermally conductive medium layer between the inner liner (4) and the annular heating element; The annular heating element is a flexible heating film or a nano-alloy heating ring. It utilizes its flexible physical properties to deform with the thermal expansion and contraction of the inner liner (4), and the fit between the annular heating element and the outer wall of the inner liner (4) is greater than or equal to 95%. The insulation layer is made of high-temperature resistant fiber material and is used to block heat from being transferred to the outer shell.

3. The inner tank outer wall heat preservation structure of an electric water heater and an electric faucet according to claim 1, characterized in that, It also includes an electrical control system, which includes: A water flow control component is provided at the water inlet pipe end of the inner liner (4); A water pressure switch, which is integrated inside or near the water flow control component, is used to sense changes in fluid pressure in the water inlet pipe and generate an on / off signal. A temperature sensor is installed at the water outlet of the inner tank (4) to collect the real-time temperature of the fluid. The safety control module is electrically connected to the annular heating element, the water pressure switch, and the temperature sensor, respectively, and is used to receive signals and adjust the electrical power supplied to the annular heating element.

4. The inner tank outer wall insulation structure of an electric water heater and electric water faucet according to claim 3, characterized in that, The water pressure switch is connected in series in the power supply circuit of the annular heating element or the drive circuit of the power drive unit, and is configured to physically disconnect the power supply of the annular heating element when the fluid pressure is sensed to be lower than a preset value. The safety control module is also connected to a leakage current detection unit and a wall temperature monitoring unit, with the probe of the wall temperature monitoring unit attached to the outer wall of the inner liner (4).

5. The inner tank outer wall insulation structure of an electric water heater and electric water faucet according to claim 4, characterized in that, The inner liner (4) is made of 304 stainless steel or ceramic. The material of the thermally conductive coating is selected from graphene composite material or nano-aluminum nitride material; The thickness of the insulation component (3) is configured such that the thermal resistance from the annular heating element toward the insulation layer is much greater than the thermal resistance toward the inner liner (4).

6. A heating method for the outer wall of the inner tank of an electric water heater and an electric water faucet, based on the inner tank outer wall insulation structure of an electric water heater and an electric water faucet as described in any one of claims 1 to 5, characterized in that, Includes the following steps: Standby monitoring steps: In standby mode, the leakage current data of the circuit and the wall temperature data of the inner liner (4) are monitored in real time through the safety control module. When the data is within the safe threshold range, standby mode is maintained. Water flow triggering step: In response to the water flow pressure signal generated by the opening of the water flow control component, the water pressure switch is closed to connect the power supply circuit of the internal annular heating element of the heat preservation component (3); Thermostatic adjustment steps: The real-time fluid temperature at the outlet of the inner tank (4) is collected by the temperature sensor. The safety control module adjusts the electric power delivered to the ring heating body according to the difference between the set temperature and the real-time fluid temperature using the proportional-integral-differential algorithm. Water and power outage procedure: In response to the disappearance of water pressure signal caused by the shutdown of water flow control component, disconnect the water pressure switch and physically cut off the power supply circuit of the ring heating element.

7. The heating method for the outer wall of the inner tank of an electric water heater and electric water faucet according to claim 6, characterized in that, The water flow triggering step specifically includes: When the fluid pressure in the inlet pipe pushes the water pressure switch to close, the safety control module directly outputs a preset initial power command to the annular heating element before receiving feedback data from the temperature sensor. The initial power command is configured to overcome the thermal inertia of the inner liner (4) wall and the thermally conductive coating, and to establish a temperature gradient on the outer wall of the inner liner (4).

8. The heating method for the outer wall of the inner tank of an electric water heater and electric water faucet according to claim 6, characterized in that, The temperature control step specifically includes: Calculate the temperature deviation, which is the difference between the set temperature and the real-time fluid temperature; The temperature deviation is calculated based on the proportional gain coefficient, integral gain coefficient, and derivative gain coefficient to obtain the control quantity; The power drive unit generates a corresponding pulse width modulation signal or conduction angle trigger signal according to the control quantity, and drives the annular heating element to work. The heat generated by the annular heating element passes through the heat-conducting coating and the wall of the inner liner (4) to the internal fluid, and the heat insulation layer blocks the heat from being transferred to the outer shell.

9. The heating method for the outer wall of the inner tank of an electric water heater and electric water faucet according to claim 6, characterized in that, The standby monitoring steps specifically include: The residual current value of the main circuit is monitored by a zero-sequence current transformer. When the residual current value is greater than or equal to the preset safety threshold, the tripping mechanism is triggered to cut off the main power supply of the system and lock it. The wall temperature is monitored by a temperature probe attached to the outer wall of the inner liner (4). When the wall temperature exceeds the preset dry burning threshold, the heating output signal is blocked.

10. The heating method for the outer wall of the inner tank of an electric water heater and electric water faucet according to claim 6, characterized in that, The water and power outage procedure also includes a waste heat management process: After the water pressure switch is disconnected and the power is cut off, the heat insulation layer on the outer side of the heat insulation component (3) is used to block the residual heat of the annular heating element and the inner tank (4) wall from dissipating to the external environment. The residual heat is transferred to the static fluid inside the inner liner (4) through the thermally conductive coating to slow down the rate of temperature drop of the fluid inside the inner liner (4).

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