Split hot water heater system

Abstract

The application discloses a split type water heater and a cooperative control method thereof, and belongs to the technical field of household water heating equipment. The core of the method is that cold water is firstly heated by a low-power (less than or equal to 3 kW) instant heating module; the water temperature in a water storage tank is monitored in real time; and the working states of the instant heating module and a safe low-voltage (less than 36 V) auxiliary heating element in the water storage tank are cooperatively controlled based on comparison of the water temperature and a set value. The system comprises the instant heating module, the water storage tank module and an intelligent control unit for executing the method. The metal heating body of the instant heating module and the outer wall of the water storage tank module are both coated with an environment-friendly heat insulation layer. Through the cooperative control logic, the instant heating module bears most of the heating load, and the auxiliary element only supplements accurate energy, so that the high energy consumption problem of the traditional water storage type water heater caused by repeated heating is fundamentally solved, and the water heater has the advantages of anti-scalding, low-power safety and high hot water utilization rate.

Description

Technical Field

[0001] This invention relates to the field of household hot water equipment technology, and in particular to a split-type water heater system based on a collaborative control strategy and its operating method, which aims to significantly improve energy efficiency ratio and safety of use. Background Technology

[0002] In the current domestic water heater market, both instantaneous and storage-type water heaters have their inherent drawbacks. Instantaneous water heaters require enormous power (typically >8kW), limiting their application in ordinary households. Storage-type water heaters, on the other hand, suffer from significant energy consumption due to repeated heating and maintaining the temperature of the entire tank of water, resulting in energy waste from "heat preservation" and "residual hot water," leading to low energy efficiency. Existing separate solutions that combine both types are mostly just simple series connections in terms of physical structure, with rudimentary control logic. The instantaneous heating unit and the storage unit typically operate independently, lacking intelligent decision-making and coordination based on the real-time status of the system, thus failing to achieve global energy efficiency optimization. For example, the heater in the storage tank often starts unconditionally, unable to dynamically adjust according to the output water temperature of the instantaneous heating unit, resulting in unresolved energy waste. Therefore, there is an urgent need for an intelligent collaborative control method to fundamentally optimize energy flow and achieve ultimate energy efficiency. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of the prior art and provide a split-type water heater system. Through the coordinated structural design of each component of the system and the intelligent decision-making logic of the control unit, the working load of the instant heating module and the heat storage module is dynamically allocated to achieve precise on-demand energy allocation and maximize energy efficiency.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] A split-type water heater system includes: an instant heating module comprising an electromagnetic heating unit, a heating element, and a water flow detection unit, wherein the outer wall of the heating element is covered with a first heat insulation layer; a water storage tank module, separately connected to the instant heating module via a pipeline, wherein an auxiliary heating element and a temperature sensor are internally provided, and the outer wall of the water storage tank module is covered with a second heat insulation layer; and a control unit, wherein its signal input terminal is electrically connected to the water flow detection unit and the temperature sensor, and its signal output terminal is electrically connected to the electromagnetic heating unit and the auxiliary heating element; the rated power P1 of the instant heating module is ≤3000W, and the instant heating module is configured to: activate when the water flow detection unit detects incoming water flow, heat the flowing cold water at the rated power P1, and deliver the heated water to the water storage tank module; the operating voltage of the auxiliary heating element is below 36V AC or 60V. DC safety extra-low voltage; the control unit is configured to: acquire the actual water temperature T in the water storage tank module detected by the temperature sensor in real time, and compare the actual water temperature T with the target water temperature Ts set by the user: if T < Ts - ΔT1, where ΔT1 is the first preset deviation, with a value range of 3℃ to 5℃, then the control unit starts the auxiliary heating element to heat the water in the tank until T ≥ Ts; if T ≥ Ts - ΔT1, then the control unit controls the auxiliary heating element to remain in a non-working state.

[0006] As a preferred embodiment, the instant heating module operates continuously during water supply, and the operation of the auxiliary heating element depends solely on the actual water temperature T in the water storage tank module obtained by the control unit.

[0007] As a preferred embodiment, when water usage stops, if the control unit detects that T < Ts - ΔT2, where ΔT2 is a second preset deviation and ΔT2 > ΔT1, then the control unit activates the auxiliary heating element for intermittent heating to maintain the water temperature within the range of [Ts - ΔT2, Ts].

[0008] As a preferred embodiment, the water inlet of the water storage tank module is located at the bottom of the tank body and extends through an inner tube to a height of 50mm±10mm from the top bottom of the tank body; the water outlet of the water storage tank module is located at the bottom of the tank body and extends through an inner tube to a height of 50mm±10mm from the bottom surface of the tank body.

[0009] As a preferred embodiment, the rated power P2 of the auxiliary heating element satisfies: P2 < 0.2 × P1, and P2 ≤ 300W.

[0010] As a preferred embodiment, it also includes a bypass pipeline and an electric switching valve, wherein the control unit is electrically connected to the electric switching valve; the control unit can automatically control the electric switching valve according to the user's manual command or the inlet water temperature, and selectively connect the outlet pipeline of the instant heating module directly to the water terminal to bypass the water storage tank module.

[0011] This invention, through the aforementioned system structure and control method, combined with the thermal insulation design of the instant heating module and the water storage tank, brings significant beneficial effects: ① Extreme energy efficiency: By forcibly prioritizing the use of the instant heating module's energy through the control unit's decision logic, auxiliary heating is only activated as a "backup" when necessary, resulting in extremely low energy consumption (tested to be <5%). Compared to traditional 60L storage water heaters, it achieves an energy saving rate of over 40%. ② Absolute safety and anti-scalding: The dual safety design (instant heating module water-electricity separation + water storage tank safe voltage heating) completely eliminates the risk of electric shock; the thermal insulation layer of the instant heating module's metal heating element and the outer wall of the water storage tank effectively prevents users from being scalded, with surface temperatures below 50℃. ③ Intelligence and economy: The low-power instant heating module is grid-friendly and easy to install. The system can intelligently switch modes according to the season and water usage habits to achieve optimal economic operation. Attached Figure Description

[0012] Figure 1 This is a schematic diagram illustrating the structural principle and control signal flow of the split-type water heater system of the present invention; Figure 2 This is the system control logic flowchart of the present invention.

[0013] Reference numerals: 100, Instantaneous heating module; 110, Electromagnetic heater; 120, Thin metal water tank; 121, Hot water exchange tank inlet; 122, Hot water exchange tank outlet; 130, Water flow sensor; 200, Water storage tank module; 201, Water storage tank inlet; 202, Water storage tank outlet; 203, Inner pipe (or outlet extension pipe); 210, Auxiliary heating element (low pressure); 220, Temperature sensor; 230, Water level observation tube; 240, Temperature display control unit; 300, Control unit; 400, Water terminal (e.g., shower head); 500, Bypass pipe and valve; 600, Low-voltage power adapter. Detailed Implementation

[0014] The present invention will now be described in further detail with reference to the accompanying drawings. It should be noted that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention.

[0015] See Figures 1 to 2 The split-type water heater system in this embodiment consists of an instant heating module 100, a water storage tank module 200, a control unit 300, and a piping system.

[0016] The instant heating module 100 is centered around an electromagnetic heater 110 with a power of P1=2500W. A flat-tube hot water exchange tank 120 (40mm thick) made of 304 stainless steel is tightly attached to the heating plate. The hot water exchange tank 120 is covered with a first insulation layer of environmentally friendly high-temperature resistant insulation material (such as epoxy resin board) with a thickness of not less than 10mm, ensuring that its outer surface temperature remains below 50℃ under any operating conditions, preventing scalding and reducing heat loss. A water flow sensor 130 is installed at the inlet 121 of the hot water exchange tank 120, and the outlet 122 is located diagonally opposite it. The water flow signal is sent to the control unit 300.

[0017] The water storage tank module 200 is a hanging pressure-bearing insulated water tank. Its outer shell consists of an inner liner, a polyurethane foam insulation layer, and an outer metal shell, forming a second insulation layer to ensure that its outer surface temperature is close to the ambient temperature. Its inlet 201 is located at the bottom and connects to the outlet 122 of the instant heating module. The outlet 202 is located at the bottom and connects to an inner pipe 203 extending to 50mm from the bottom of the tank. A titanium alloy electric heating tube with a rated voltage of DC24V and a power of P2=200W is installed at the bottom of the tank as an auxiliary heating element 210. This P2 value (200W) is 8% based on P1=2500W. Through thermodynamic simulation and experimental verification, this ratio can control the auxiliary energy consumption to within 5% in most water usage scenarios, making it the optimal choice for achieving the energy efficiency target of this invention. A PT1000 temperature sensor 220 is inserted in the middle of the tank. A transparent water level tube 230 and a temperature display 240 are located on the front of the tank. The minimum warning level is set at 5% of the total height.

[0018] The control unit 300 is based on a microcontroller (MCU, such as the STM32 series) and is equipped with a relay drive circuit, a signal conditioning circuit, and a power supply module. It receives signals from the water flow sensor 130 and the temperature sensor 220, and controls the power relays of the electromagnetic heater 110 and the auxiliary heating element 210.

[0019] The system works as follows (see Figure 2 ):

[0020] After the system is powered on, the control unit 300 is in standby mode.

[0021] The control unit 300 reads the signal from the water flow sensor 130 in real time: if there is no water flow signal, it waits in a loop; if there is a water flow signal, the control unit 300 immediately starts the electromagnetic heater 110, which operates at a power of 2500W to heat the flowing cold water and delivers the heated water to the water storage tank module 200.

[0022] During water supply, the control unit 300 reads the actual water temperature T in the water storage tank module 200 detected by the temperature sensor 220 in real time and compares the actual water temperature T with the target water temperature Ts set by the user. In this embodiment, the user sets Ts=45℃ and ΔT1=3℃ (this value is set based on the range where the human body is not sensitive to changes in shower water temperature). If T<42℃ (i.e., T<Ts-ΔT1), the control unit 300 immediately activates the auxiliary heating element 210 for supplemental heating; if T≥42℃ (i.e., T≥Ts-ΔT1), the control unit 300 keeps the auxiliary heating element 210 off, keeping it in a zero-power consumption state.

[0023] The control unit 300 continuously monitors the water flow signal until water use ends. When the water flow stops, the control unit 300 cuts off the power to the electromagnetic heater 110.

[0024] After water usage is stopped, the control unit 300 determines whether to enter the heat preservation mode. If the user has activated the heat preservation function, ΔT2 is set to 5℃ (i.e., 40℃). When the control unit 300 detects that T < 40℃, it controls the auxiliary heating element 210 to operate intermittently using a hysteresis control method to maintain the water temperature between 40-45℃; if the user has not activated the heat preservation function, the entire system enters standby mode.

[0025] Bypass mode: Users can manually switch via the button on the control unit 300, or the control unit 300 can automatically determine (when the inlet water temperature is higher than 40℃) and control the electric switching valve to connect the outlet pipe of the instant heating module 100 directly to the shower head 400, bypassing the water storage tank module 200, to achieve a high-efficiency instant heating mode in summer and further save energy.

[0026] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A split-type water heater system, characterized in that, include: The instant heating module includes an electromagnetic heating unit, a heated body, and a water flow detection unit. The outer wall of the heated body is covered with a first heat insulation layer. A water storage tank module is separately connected to the instant heating module via pipelines. It contains an auxiliary heating element and a temperature sensor. The outer wall of the water storage tank module is covered with a second heat insulation layer. A control unit has its signal input terminal electrically connected to the water flow detection unit and the temperature sensor, and its signal output terminal electrically connected to the electromagnetic heating unit and the auxiliary heating element. The rated power of the instant heating module P1 ≤ 3000W. The operating voltage of the auxiliary heating element is a safety extra-low voltage lower than 36V AC or 60V DC.

2. The system according to claim 1, characterized in that, The instant heating module operates continuously during water supply, and the operation of the auxiliary heating element depends solely on the actual water temperature T in the water storage tank module obtained by the control unit.

3. The system according to claim 1 or 2, characterized in that, The water inlet of the water storage tank module is located at the bottom of the tank body and extends through an inner tube to a height of 50mm±10mm from the top of the tank body; the water outlet of the water storage tank module is located at the bottom of the tank body and extends through an inner tube to a height of 50mm±10mm from the bottom of the tank body.

4. The system according to claim 1, characterized in that, The rated power P2 of the auxiliary heating element satisfies: P2 < 0.2 × P1, and P2 ≤ 300W.

5. The system according to claim 1, characterized in that, It also includes a bypass pipeline and an electric switching valve. The electric switching valve is electrically connected to the control unit. The electric switching valve is located between the water outlet pipeline of the instant heating module and the water terminal, and is used to selectively connect the water outlet pipeline of the instant heating module directly to the water terminal to bypass the water storage tank module.

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