A control method and system for a liquid fuel water heater

Abstract

The present invention relates to the field of water heater control technology, and more specifically, to a control method and system for a liquid fuel water heater. The water heater system includes a water inlet, a solenoid valve, a combustion chamber, a water flow sensor, and a water outlet. The water inlet is connected to the tap water network, and water is input into the water heater for heating. A temperature control model is established to obtain a temperature difference threshold interval, and the combustion intensity of the combustion chamber is adjusted according to the corresponding threshold interval; after the water flow is interrupted, the water flow is stopped from being heated. By establishing a temperature control model, the present invention can more accurately obtain the difference between the water inlet and the preset temperature, and map it to the corresponding temperature difference threshold interval, so that the combustion intensity of the combustion chamber can be accurately adjusted according to the actual temperature difference, thereby achieving precise control of the water temperature. Whether in the case of a small temperature difference or a large temperature difference, it can ensure that the outlet water temperature is stable within the range required by the user, thereby improving the user's experience.

Description

Technical Field

[0001] The present invention relates to the technical field of water heater control, and in particular to a control method and system for a liquid fuel water heater. Background Art

[0002] In modern life, hot water supply is an indispensable part of people's daily life and industrial production. With the continuous growth of energy demand and the improvement of environmental awareness, liquid fuel water heaters, as an efficient and convenient hot water supply equipment, have received widespread attention.

[0003] When the existing water heater is in use, after the water is disconnected, the water heater stops supplying liquid fuel, but there will still be a small amount of residual fuel attached to the combustion chamber and continue to burn. The water temperature in the pipeline will rise sharply to about 80 degrees. When the water is turned on again, it is easy to cause scalds to people. Moreover, in summer, the water flow temperature in the tap water pipe is relatively high. During use, the water heater still adopts normal combustion, resulting in excessively high water flow temperature, which is easy to cause scalds to people and also causes waste of combustion.

[0004] Therefore, a control method and system for a liquid fuel water heater are proposed. Summary of the invention

[0005] The object of the present invention is to provide a control method and system for a liquid fuel water heater to solve the problems raised in the above background technology.

[0006] In order to solve the above technical problems, one of the purposes of the present invention is to provide a control method for a liquid fuel water heater, characterized in that: the water heater system includes a water inlet, a solenoid valve, a combustion chamber, a water flow sensor and a water outlet, the water inlet is connected to the tap water network, and the input water enters the water heater for heating, the combustion chamber is connected to a secondary water tank and a heat exchanger, the water flow sensor is used to monitor the water flow state in real time, the water heater system also includes a preheating recovery device, and the water outlet is connected to the user end; the control method includes:

[0007] S1, identifying the water flow signal and obtaining the water flow temperature at the water inlet and outlet of the water heater;

[0008] S2. Set a temperature difference threshold interval, obtain the temperature difference between the water inlet and the preset temperature; map the difference to the corresponding temperature difference threshold interval;

[0009] S3, establish a temperature control model, obtain the temperature difference threshold interval in S2, and adjust the combustion intensity of the combustion chamber according to the corresponding threshold interval;

[0010] S4. After the water flow is interrupted, the water flow is stopped from being heated, and the energy from the combustion of the residual fuel is recovered to avoid continuous heating.

[0011] As a further improvement of the present technical solution, S1 determines whether there is water flowing into the water heater through the water inlet according to the water flow state monitored by the water flow sensor. If the water flow sensor detects water flow, it enters the heating mode; if there is no water flow, it enters the standby mode.

[0012] As a further improvement of the present technical solution, in S1, a first sensor and a second sensor are arranged at the water inlet and the water outlet of the water heater, the first sensor senses the water flow temperature at the water inlet, and the second sensor senses the water flow temperature at the water outlet.

[0013] As a further improvement of the technical solution, the temperature difference threshold interval is set in S2, and the specific steps are as follows:

[0014] S2.1. Set multiple temperature difference threshold intervals according to actual needs and the performance characteristics of the water heater;

[0015] S2.2. Monitor the water temperature at the water inlet in real time, compare it with the preset target water temperature, calculate the difference between the two, compare the calculated difference with the set temperature difference threshold range, and map the difference to the corresponding temperature difference threshold range.

[0016] As a further improvement of this technical solution, the S2.2 algorithm formula is as follows:

[0017] : Inlet water temperature; : preset temperature;

[0018] : The temperature difference between the water inlet and the preset temperature, that is = - ;

[0019] I: Combustion intensity, which can be measured in different units according to actual conditions, such as fuel flow rate and combustion power;

[0020] , : Boundary values ​​of different temperature difference threshold intervals, for example It can be the boundary value of the small temperature difference range and the medium temperature difference range. It is the boundary value between the medium temperature difference range and the large temperature difference range;

[0021] The formula for determining combustion intensity based on temperature difference is:

[0022] When 0≤ < When the temperature is small, a lower combustion intensity can be used. ;

[0023] when ≤ < When the temperature is in the medium range, use moderate combustion intensity. ;

[0024] when ≥ When in a large temperature difference range, a higher combustion intensity is used .

[0025] As a further improvement of the technical solution, the step S3 of establishing a temperature control model comprises the following steps:

[0026] S3.1. Collect the combustion intensity data of the combustion chamber under different water inlet temperature, preset temperature, water flow rate, ambient temperature and other conditions and the corresponding water outlet temperature data, analyze the relationship between these data, and find out the key factors affecting the water temperature change;

[0027] S3.2. Use a multiple linear regression model, taking the water inlet temperature, preset temperature difference, water flow rate, ambient temperature, etc. as input variables, and the combustion intensity of the combustion chamber as the output variable, and determine the parameters of the model by training the collected data;

[0028] S3.3. Verify the constructed temperature control model and evaluate the accuracy and reliability of the model.

[0029] As a further improvement of the present technical solution, S3 obtains the temperature difference threshold interval in S2.2, adjusts the combustion strategy in the combustion chamber according to the threshold interval, continuously monitors the water outlet temperature and user feedback, and adjusts the combustion intensity.

[0030] As a further improvement of the technical solution, avoiding continuous heating in S4 includes the following steps:

[0031] S4.1. When it is detected that the water flow speed decreases to a certain level or stops completely, it is judged that the water flow is interrupted;

[0032] S4.2. Close the solenoid valve, cut off the fuel supply, stop heating the water flow, and at the same time, turn off the ignition device of the combustion chamber to ensure that the combustion stops, and start the residual fuel combustion energy recovery system to recover the residual fuel combustion energy.

[0033] The second object of the present invention is to provide a control system for a liquid fuel water heater, comprising a control method for a liquid fuel water heater as described in any one of the above, including a water temperature identification unit, a temperature mapping unit, a temperature control model unit and an energy recovery unit;

[0034] The water temperature identification unit is used to identify the water flow signal and obtain the water flow temperature at the water inlet and outlet of the water heater;

[0035] The temperature mapping unit is used to set the temperature difference threshold interval, obtain the temperature difference between the water inlet and the preset temperature; and map the difference to the corresponding temperature difference threshold interval;

[0036] The temperature control model unit is used to establish a temperature control model, obtain the temperature difference threshold interval mapped in 200, and adjust the combustion intensity of the combustion chamber according to the corresponding threshold interval;

[0037] The energy recovery unit is used to recover the residual fuel combustion energy to avoid continuous heating.

[0038] Compared with the prior art, the present invention has the following beneficial effects:

[0039] 1. In the control method of a liquid fuel water heater, by establishing a temperature control model, the difference between the water inlet and the preset temperature can be obtained more accurately and mapped to the corresponding temperature difference threshold range, so that the combustion intensity of the combustion chamber can be accurately adjusted according to the actual temperature difference, thereby achieving precise control of the water temperature. Whether in the case of small or large temperature difference, it can ensure that the water outlet temperature is stable within the range required by the user, thereby improving the user experience.

[0040] 2. In the control method of this liquid fuel water heater, by setting the temperature difference threshold interval and mapping the difference to the corresponding interval, the combustion intensity of the combustion chamber can be controlled more accurately, thereby achieving accurate and rapid adjustment of the water temperature. Under large temperature difference conditions, the water temperature can be quickly increased, the waiting time can be reduced, and the energy utilization efficiency can be improved. At the same time, the combustion intensity can be reasonably controlled to reduce overheating and wear of the combustion chamber and extend the service life of the water heater.

[0041] 3. In the control method of a liquid fuel water heater, stopping heating after the water flow is interrupted can avoid overheating damage to the water heater and pipelines, reducing safety risks. At the same time, it avoids accidents such as scalding caused by excessive water temperature due to continuous heating, improves the safety of use, and recycles the residual fuel combustion energy. The recovered heat can be used to heat the water flow first when there is subsequent water flow, thereby improving energy utilization efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 It is the overall flow chart of the present invention;

[0043] Figure 2 It is a flow chart of setting the temperature difference threshold interval of the present invention;

[0044] Figure 3 It is a flowchart of building a temperature control model of the present invention;

[0045] Figure 4 It is a flow chart of energy recovery process of the present invention;

[0046] Figure 5 It is a schematic diagram of the working principle of the present invention.

[0047] The meaning of each number in the figure is:

[0048] 100. Water temperature identification unit; 200. Temperature mapping unit; 300. Temperature control model unit; 400. Energy recovery unit. DETAILED DESCRIPTION

[0049] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0050] One of the purposes of the present invention is to Figure 1-Figure 5 As shown, a control method for a liquid fuel water heater is provided. The water heater system includes a water inlet, a solenoid valve, a combustion chamber, a water flow sensor and a water outlet. The water inlet is connected to a tap water network, and water is input into the water heater for heating. The combustion chamber is connected to a secondary water tank and a heat exchanger. The water flow sensor is used to monitor the water flow state in real time. The water heater system also includes a waste heat recovery device, and the water outlet is connected to a user end. The control method includes:

[0051] S1, identifying the water flow signal and obtaining the water flow temperature at the water inlet and outlet of the water heater;

[0052] S1 determines whether there is water flowing into the water heater through the water inlet according to the water flow state monitored by the water flow sensor. If the water flow sensor detects water flow, it enters the heating mode; if there is no water flow, it enters the standby mode.

[0053] In S1, a first sensor and a second sensor are arranged at the water inlet and the water outlet of the water heater, wherein the first sensor senses the water flow temperature at the water inlet, and the second sensor senses the water flow temperature at the water outlet.

[0054] A high-precision water flow sensor is installed at the water inlet of the water heater. After installation, the water flow sensor is calibrated to ensure that it can accurately detect the presence and flow rate of water flow. The sensor transmits the monitored water flow information to the water heater control system. The control system determines whether there is water flowing into the water heater through the water inlet based on the preset threshold and algorithm. If the water flow rate is greater than a certain set value, it is considered that there is water flowing; if the water flow rate is less than or equal to the set value, it is considered that there is no water flow. If the control system determines that there is water flowing into the water heater through the water inlet, it enters the heating mode. In the heating mode, the water heater starts the burner according to the preset heating parameters to heat the water flow. If the control system determines that there is no water flowing through the water inlet, it enters the standby mode. In the standby mode, the water heater stops heating and turns off the burner to save energy. At the same time, the control system can enter a low-power state to reduce power consumption, reduce the operating time and wear of the equipment, and extend the service life of the water heater.

[0055] S2. Set a temperature difference threshold interval, obtain the temperature difference between the water inlet and the preset temperature; map the difference to the corresponding temperature difference threshold interval;

[0056] In S2, the temperature difference threshold interval is set. The specific steps are as follows:

[0057] S2.1. Set multiple temperature difference threshold intervals according to actual needs and the performance characteristics of the water heater;

[0058] S2.2. Monitor the water temperature at the water inlet in real time, compare it with the preset target water temperature, calculate the difference between the two, compare the calculated difference with the set temperature difference threshold range, and map the difference to the corresponding temperature difference threshold range.

[0059] The S2.2 algorithm formula is as follows:

[0060] : Inlet water temperature; : preset temperature;

[0061] : The temperature difference between the water inlet and the preset temperature, that is = - ;

[0062] I: Combustion intensity, which can be measured in different units according to actual conditions, such as fuel flow rate and combustion power;

[0063] , : Boundary values ​​of different temperature difference threshold intervals, for example It can be the boundary value of the small temperature difference range and the medium temperature difference range. It is the boundary value between the medium temperature difference range and the large temperature difference range;

[0064] The formula for determining combustion intensity based on temperature difference is:

[0065] When 0≤ < When the temperature is small, a lower combustion intensity can be used. , for example I= + ,in and is a coefficient determined experimentally or empirically;

[0066] when ≤ < When the temperature is in the medium range, use moderate combustion intensity. , for example I= + ;

[0067] when ≥ When in a large temperature difference range, a higher combustion intensity is used , for example I= + .

[0068] According to actual needs and the performance characteristics of the water heater, multiple temperature difference threshold intervals are set. For example, a small temperature difference interval of 0℃-10℃, a medium temperature difference interval of 10℃-20℃, a large temperature difference interval of above 20℃, etc. can be set, and the water inlet and outlet temperatures can be sensed in real time through sensors.

[0069] The calculated difference is compared with the set temperature difference threshold range to determine the range the difference belongs to. For example, if the difference is 15°C, it belongs to the medium temperature difference range.

[0070] By setting the temperature difference threshold interval and mapping the difference to the corresponding interval, the combustion intensity of the combustion chamber can be controlled more accurately, thereby achieving accurate and rapid adjustment of the water temperature. Under large temperature difference conditions, the water temperature can be quickly increased, waiting time can be reduced, and energy efficiency can be improved. At the same time, reasonable control of the combustion intensity can reduce overheating and wear of the combustion chamber and extend the service life of the water heater.

[0071] S3, establish a temperature control model, obtain the temperature difference threshold interval in S2, and adjust the combustion intensity of the combustion chamber according to the corresponding threshold interval;

[0072] In order to quickly and accurately output water at the set temperature when using water and save resources, S3 establishes a temperature control model, including the following steps:

[0073] S3.1. Collect the combustion intensity data of the combustion chamber under different water inlet temperature, preset temperature, water flow rate, ambient temperature and other conditions and the corresponding water outlet temperature data, analyze the relationship between these data, and find out the key factors affecting the water temperature change;

[0074] S3.2. Use a multiple linear regression model, taking the water inlet temperature, preset temperature difference, water flow rate, ambient temperature, etc. as input variables, and the combustion intensity of the combustion chamber as the output variable, and determine the parameters of the model by training the collected data;

[0075] S3.3. Verify the constructed temperature control model and evaluate the accuracy and reliability of the model.

[0076] The temperature sensor is used to monitor the water inlet temperature and the preset temperature in real time, and the difference between the two, i.e., the temperature difference, is calculated. The temperature difference calculated in real time is compared with the set temperature difference threshold range to determine the range to which the temperature difference belongs. According to the range to which the temperature difference belongs, the corresponding combustion intensity adjustment strategy is adopted, for example:

[0077] When the temperature difference is in a small temperature difference range, reduce the combustion intensity to save fuel and reduce energy consumption. This can be achieved by reducing the fuel flow rate, reducing the combustion power, etc.

[0078] When the temperature difference is in the medium temperature difference range, maintain moderate combustion intensity to quickly increase the water temperature, and adjust the fuel flow and combustion power according to the actual situation so that the water temperature can reach the preset temperature within a reasonable time;

[0079] When the temperature difference is in a large temperature difference range, the combustion intensity is increased to reach the preset temperature as soon as possible, which can increase the fuel flow rate and improve the combustion power;

[0080] Continuously monitor the water outlet temperature and user feedback, and adjust the combustion intensity according to the actual situation. If the water outlet temperature is too high or too low, the combustion intensity can be adjusted appropriately to meet the user's needs;

[0081] By establishing a temperature control model, obtaining the temperature difference threshold range and adjusting the combustion intensity of the combustion chamber according to the range, precise temperature control of the liquid fuel water heater can be achieved, energy utilization efficiency can be improved, equipment life can be extended, and users' different needs for water temperature can be met.

[0082] By establishing a temperature control model, the difference between the water inlet and the preset temperature can be obtained more accurately and mapped to the corresponding temperature difference threshold range. This allows the combustion intensity of the combustion chamber to be precisely adjusted according to the actual temperature difference, thereby achieving precise control of the water temperature. Whether in the case of small or large temperature differences, it can ensure that the water outlet temperature is stable within the range required by the user, thereby improving the user experience.

[0083] When water flows out of the water outlet, in order to improve the accuracy of the water flow temperature, the temperature difference threshold interval in S2.2 is obtained, the combustion strategy in the combustion chamber is adjusted according to the threshold interval, the water outlet temperature and user feedback are continuously monitored, and the combustion intensity is adjusted. The specific steps are as follows:

[0084] Monitor the water inlet temperature and preset temperature in real time, calculate the difference between the two, that is, the current temperature difference, and use temperature sensors and other equipment to accurately measure the water inlet and preset temperatures to ensure the accuracy of temperature difference calculation;

[0085] If the current temperature difference is greater than 0, it means that the water inlet heating temperature is too high, and the fuel supply should be reduced. If the current temperature difference is less than 0, it means that the water inlet heating temperature is too low, and the fuel supply should be increased to improve the combustion intensity so as to reach the preset temperature as soon as possible, thereby improving the accuracy of the water flow temperature.

[0086] S4. After the water flow is interrupted, the water flow is stopped from being heated, and the energy from the combustion of the residual fuel is recovered to avoid continuous heating.

[0087] After the water is cut off, the water heater stops supplying liquid fuel, but a small amount of residual fuel will still remain in the combustion chamber and continue to burn. The water temperature in the pipe will rise sharply to around 80 degrees, which can easily cause burns to users when using it.

[0088] Avoiding continuous heating in S4 includes the following steps:

[0089] S4.1. When it is detected that the water flow speed decreases to a certain level or stops completely, it is judged that the water flow is interrupted; S4.2. The solenoid valve is closed, the fuel supply is cut off, and the heating of the water flow is stopped. At the same time, the ignition device of the combustion chamber is closed to ensure that the combustion stops, and the residual fuel combustion energy recovery system is started to recover the residual fuel combustion energy.

[0090] During the operation of the water heater, the water flow is continuously monitored by a water flow sensor. The water flow sensor can adopt a variety of technologies, such as Hall effect sensor, turbine flow meter, etc., which can accurately detect the presence and flow rate of water flow.

[0091] When the water flow sensor detects that the water flow speed decreases to a certain level or stops completely, it is judged that the water flow is interrupted. A threshold can be set. For example, when the water flow speed is less than 0.1 liters per second, it is considered that the water flow is interrupted.

[0092] Once the water flow is confirmed to be interrupted, immediately close the solenoid valve, cut off the fuel supply, stop heating the water flow, and at the same time, turn off the ignition device of the combustion chamber to ensure that the combustion stops;

[0093] After the water flow is interrupted, the residual fuel combustion energy recovery system is activated. This system may include a heat exchanger that transfers the residual heat in the combustion chamber to a heat storage device, such as a preheat recovery device.

[0094] Stopping heating after the water flow is interrupted can avoid overheating damage to the water heater and pipes, reducing safety risks. At the same time, it avoids accidents such as scalding caused by excessive water temperature due to continuous heating, improves the safety of use, and recycles the residual fuel combustion energy. The recovered heat can be used to heat the water flow first when there is subsequent water flow, improving energy utilization efficiency.

[0095] The second object of the present invention is to provide a control system for a liquid fuel water heater, including any one of the above-mentioned methods for controlling a liquid fuel water heater, including a water temperature identification unit 100, a temperature mapping unit 200, a temperature control model unit 300 and an energy recovery unit 400;

[0096] The water temperature recognition unit 100 is used to recognize the water flow signal and obtain the water flow temperature at the water inlet and outlet of the water heater;

[0097] The temperature mapping unit 200 is used to set the temperature difference threshold interval, obtain the temperature difference between the water inlet and the preset temperature, and map the difference to the corresponding temperature difference threshold interval;

[0098] The temperature control model unit 300 is used to establish a temperature control model, obtain the temperature difference threshold interval mapped in 200, and adjust the combustion intensity of the combustion chamber according to the corresponding threshold interval;

[0099] The energy recovery unit 400 is used to recover the residual fuel combustion energy to avoid continuous heating.

[0100] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. The above embodiments and descriptions are only preferred examples of the present invention and are not intended to limit the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A control method for a liquid fuel water heater, characterized in that: The water heater system includes a water inlet, a solenoid valve, a combustion chamber, a water flow sensor and a water outlet. The water inlet is connected to the tap water network, and the input water enters the water heater for heating. The combustion chamber is connected to a secondary water tank and a heat exchanger. The water flow sensor is used to monitor the water flow state in real time. The water heater system also includes a preheating recovery device. The water outlet is connected to the user end. The control method includes: S1, identifying the water flow signal and obtaining the water flow temperature at the water inlet and outlet of the water heater; S2. Set a temperature difference threshold interval, obtain the temperature difference between the water inlet and the preset temperature; map the difference to the corresponding temperature difference threshold interval; In S2, the temperature difference threshold interval is set, and the specific steps are as follows: S2.

1. Set multiple temperature difference threshold intervals according to actual needs and the performance characteristics of the water heater; S2.2, monitor the water temperature of the water inlet in real time, compare it with the preset target water temperature, calculate the difference between the two, compare the calculated difference with the set temperature difference threshold interval, and map the difference to the corresponding temperature difference threshold interval; S3, establish a temperature control model, obtain the temperature difference threshold interval in S2, and adjust the combustion intensity of the combustion chamber according to the corresponding threshold interval; The step S3 establishes a temperature control model, including the following steps: S3.

1. Collect the combustion intensity data of the combustion chamber under different water inlet temperature, preset temperature, water flow rate, ambient temperature and other conditions and the corresponding water outlet temperature data, analyze the relationship between these data, and find out the key factors affecting the water temperature change; S3.

2. Use a multiple linear regression model, taking the water inlet temperature, preset temperature difference, water flow rate, and ambient temperature as input variables, and the combustion intensity of the combustion chamber as the output variable, and determine the parameters of the model by training the collected data; S3.

3. Verify the constructed temperature control model and evaluate the accuracy and reliability of the model; S3 obtains the temperature difference threshold interval in S2.2, adjusts the combustion strategy in the combustion chamber according to the threshold interval, continuously monitors the water outlet temperature and user feedback, and adjusts the combustion intensity; S4. After the water flow is interrupted, the water flow is stopped from being heated, and the residual fuel combustion energy is recovered to avoid continuous heating; Avoiding continuous heating in S4 comprises the following steps: S4.

1. When it is detected that the water flow speed decreases to a certain level or stops completely, it is judged that the water flow is interrupted; S4.

2. Close the solenoid valve, cut off the fuel supply, stop heating the water flow, and at the same time, turn off the ignition device of the combustion chamber to ensure that the combustion stops, and start the residual fuel combustion energy recovery system to recover the residual fuel combustion energy.

2. A control method for a liquid fuel water heater according to claim 1, characterized in that: S1 determines whether water flows into the water heater through the water inlet according to the water flow state monitored by the water flow sensor, and enters the heating mode if the water flow sensor detects water flow; If there is no water flow, it goes into standby mode.

3. A control method for a liquid fuel water heater according to claim 2, characterized in that: In S1, a first sensor and a second sensor are arranged at the water inlet and the water outlet of the water heater, wherein the first sensor senses the water flow temperature at the water inlet, and the second sensor senses the water flow temperature at the water outlet.

4. A control method for a liquid fuel water heater according to claim 1, characterized in that: The S2.2 algorithm formula is as follows: : Inlet water temperature; : preset temperature; : The temperature difference between the water inlet and the preset temperature, that is = - ; : Combustion intensity, which can be measured in different units according to actual conditions, such as fuel flow rate and combustion power; , : Boundary values ​​of different temperature difference threshold intervals, for example It can be the boundary value of the small temperature difference range and the medium temperature difference range. It is the boundary value between the medium temperature difference range and the large temperature difference range; The formula for determining combustion intensity based on temperature difference is: When 0≤ < When the temperature is small, a lower combustion intensity can be used. ; when ≤ < When the temperature is in the medium range, use moderate combustion intensity. ; when ≥ When in a large temperature difference range, a higher combustion intensity is used .

5. A control system for a liquid fuel water heater, comprising a control method for a liquid fuel water heater according to any one of claims 1 to 4, characterized in that: It comprises a water temperature identification unit (100), a temperature mapping unit (200), a temperature control model unit (300) and an energy recovery unit (400); The water temperature identification unit (100) is used to identify the water flow signal and obtain the water flow temperature at the water inlet and outlet of the water heater; The temperature mapping unit (200) is used to set a temperature difference threshold interval, obtain a temperature difference between the water inlet and a preset temperature, and map the difference to a corresponding temperature difference threshold interval; The temperature control model unit (300) is used to establish a temperature control model, obtain the temperature difference threshold interval mapped in 200, and adjust the combustion intensity of the combustion chamber according to the corresponding threshold interval; The energy recovery unit (400) is used to recover residual fuel combustion energy to avoid continuous heating.

Images