A control method for the pressurization function of a gas water heater and a gas water heater

Abstract

The present invention discloses a control method for the pressurization function of a gas water heater and a gas water heater. The control method includes the following steps: S1: Start the pressurization function; S2: Determine whether the water flow rate detected by the water flow sensor is greater than or equal to the start-up water flow rate. If so, ignite and start the machine and turn on the water pump; if not, return to step S1; S3: Determine whether the water flow rate detected by the water flow sensor in real time is less than the shutdown water flow rate. If so, shut down and extinguish the fire and turn off the water pump; if not, enter step S4: S4: Detect the inlet water temperature in real time according to the temperature probe, and determine whether the water temperature rise per unit time is greater than the pump shutdown temperature difference △T 关泵 , if not, maintain the operation of the pressurization function and return to step S3; if so, turn off the water pump and enter step S5; S5: Determine whether the water flow rate detected by the water flow sensor is less than the shutdown water flow rate. If so, shut down and extinguish the fire; if not, restart the water pump.

Description

Technical Field

[0001] The present invention relates to the technical field of pressure boosting control for gas water heaters, and particularly relates to a control method for the pressure boosting function of a gas water heater and a gas water heater. Background Art

[0002] At present, zero - cold - water gas water heaters have become a trend in the water heater industry because they can provide hot water immediately when turned on. However, most zero - cold - water water heaters on the market do not have a water volume boosting function. The specific reasons are as follows:

[0003] The pressure boosting function control logic of conventional pressure - boosting gas water heaters on the market is as follows. Pump - on condition: After the pressure boosting function is turned on, when the water flow sensor of the water heater measures that the water flow rate > the pump - on water flow rate (about 2.5 L / min), the water pump is turned on for pressure boosting. Pump - off condition: In the pressure - boosting operation mode, when the measured water flow rate < the pump - off water flow rate (about 2.0 L / min), the water pump is turned off and the burner is extinguished.

[0004] Zero - cold - water water heaters require an external return water pipe to be arranged. When the pre - heating function is started, the built - in circulation pump operates to drive the stored water in the hot water pipe and the return water pipe to circulate and achieve pre - heating.

[0005] In the state of having a return water circulation pipeline, when the pressure boosting function is turned on, under the suction of the built - in circulation pump, part of the hot water flows back to the water inlet end of the water heater through the return water pipe. When the user closes the hot water faucet, the stored water in the pipeline circulates under the action of the water pump. There may be a phenomenon that the circulation flow rate (generally 3.5 - 5 L / min) is higher than the water heater shutdown water flow rate. The stored water continues to be heated until the outlet water temperature reaches the high - temperature protection temperature (about 75°C) before the burner is extinguished and the pump is turned off, wasting a large amount of gas and electricity. When the user re - opens the hot water faucet, the outlet water temperature is too hot, which is extremely likely to cause scalding accidents. Summary of the Invention

[0006] The present invention aims to solve at least one of the problems existing in the related art to a certain extent. For this purpose, the present invention provides a control method for the pressure boosting function of a gas water heater and a gas water heater.

[0007] A control method for the pressure boosting function of a gas water heater includes a controller, a temperature probe arranged at the water inlet end of the main water path of the gas water heater, and a water pump and a water flow sensor respectively arranged on the main water path of the gas water heater. The control method includes the following steps:

[0008] S1: Start the pressure boosting function;

[0009] S2: Judge whether the water flow rate detected by the water flow sensor is greater than or equal to the startup water flow rate. If so, ignite and start the machine and turn on the water pump; if not, return to step S1;

[0010] S3: Determine whether the water flow rate detected in real time by the water flow sensor is less than the shutdown water flow rate. If so, shut down and extinguish the fire and turn off the water pump; if not, proceed to step S4:

[0011] S4: Detect the inlet water temperature in real time according to the temperature probe, and determine whether the water temperature rise within a unit time is greater than the pump shutdown temperature difference △T 关泵 , if not, maintain the operation of the pressurization function and return to step S3; if so, turn off the water pump and proceed to step S5;

[0012] S5: Determine whether the water flow rate detected by the water flow sensor is less than the shutdown water flow rate. If so, shut down and extinguish the fire; if not, restart the water pump, maintain the operation of the pressurization function and return to step S3.

[0013] Further, in step S4, the water temperature rise within the unit time is determined according to the formula water temperature rise = T 进 - T′ 进 where T 进 is the inlet water temperature measured in real time by the temperature probe, and T′ 进 is the inlet water temperature measured before the unit time.

[0014] Further, the pump shutdown temperature difference △T 关泵 has a proportional linear relationship with the heating temperature difference △T 加热 , and the heating temperature difference △T 加热 is determined according to the formula △T 加热＝ T 设 - T 进 where T 设 is the set temperature, and T 进 is the inlet water temperature measured in real time by the temperature probe.

[0015] Further, the pump shutdown temperature difference △T 关泵 is determined according to the following formula:

[0016] When △T 加热 <△T 加热min , △T 关泵 =△T 关泵min ;

[0017] When △T 加热min ≤△T 加热 ≤△T 加热max , △T 关泵 =(△T 关泵max - △T 关泵min ) * (△T 加热 - △T 加热min ) / (△T 加热max - △T 加热min ) + △T 关泵min ;

[0018] When △T 加热 >△T 加热max , △T 关泵 =△T 关泵max ;

[0019] In the formula, △T 加热min is the minimum heating temperature difference set by the program, △T 加热max is the maximum heating temperature difference set by the program, △T 关泵min is the minimum pump - off temperature difference, △T 关泵max is the maximum pump - off temperature difference, △T 加热min corresponds to △T 关泵min , △T 加热max corresponds to △T 关泵max .

[0020] Further, the minimum heating temperature difference △T 加热min set by the program, the maximum heating temperature difference △T 加热max set by the program, the minimum pump - off temperature difference △T 关泵min and the maximum pump - off temperature difference △T 关泵max are all fixed values or are set according to the parameter setting method of the controller.

[0021] Further, the pump - off temperature difference △T 关泵 is a fixed value or is set according to the parameter setting method of the controller.

[0022] A gas water heater includes a gas water heater body, a temperature probe arranged at the water inlet end of the main water path of the gas water heater body, an operation display arranged on the gas water heater body, a water pump and a water flow sensor respectively arranged on the main water path of the gas water heater body, and a controller arranged inside the gas water heater body. The controller is electrically connected to the temperature probe, the operation display, the water pump and the water flow sensor respectively, and the controller at least has the control method for the gas water heater boosting function as described above.

[0023] Compared with the prior art, the present invention has at least the following beneficial effects:

[0024] 1. In the boosting mode with a return water circulation pipeline, after the water is turned off, by monitoring the return water temperature rise, a quick pump - off action is realized, saving gas and power consumption, and avoiding the water temperature being too hot when using water again.

[0025] 2. The pump - off temperature difference is adaptive according to the difference between the set temperature and the inlet water temperature, realizing intelligent identification and meeting the different water temperature requirements in different seasons. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a flowchart of a control method for the boosting function of a gas water heater according to the present invention;

[0027] Figure 2 Schematic diagram of the relationship between the pump - off temperature difference and the heating temperature difference for the control method of the pressurization function of a gas water heater according to the present invention;

[0028] Figure 3 Schematic diagram of the structure of a gas water heater according to the present invention and its external connection pipelines. Detailed implementation manners

[0029] In order to enable those skilled in the art to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of the technical solutions claimed by the present invention.

[0030] As Figure 1-2 shown, a control method for the pressurization function of a gas water heater includes a controller, a temperature probe provided at the water inlet end of the main water path of the gas water heater, and a water pump and a water flow sensor respectively provided on the main water path of the gas water heater. A return pipe is provided between the external hot water pipe and the cold water pipe of the gas water heater to realize the water circulation pre - heating in the pipeline of the gas water heater. A one - way valve is provided on the return pipe to prevent the water in the external cold water pipe from flowing into the external hot water pipe. The control method includes the following steps:

[0031] S1: Start the pressurization function;

[0032] S2: Judge whether the water flow detected by the water flow sensor is greater than or equal to the start - up water flow. If so, ignite and start the machine and turn on the water pump; if not, return to step S1;

[0033] S3: Judge whether the water flow detected by the water flow sensor in real - time is less than the shutdown water flow. If so, shut down and extinguish the fire and turn off the water pump; if not, enter step S4:

[0034] S4: Detect the inlet water temperature in real - time according to the temperature probe, and judge whether the water temperature rise per unit time is greater than the pump - off temperature difference △T 关泵 , if not, maintain the operation of the pressurization function and return to step S3; if so, turn off the water pump and enter step S5;

[0035] S5: Judge whether the water flow detected by the water flow sensor is less than the shutdown water flow. If so, shut down and extinguish the fire; if not, restart the water pump, maintain the operation of the pressurization function and return to step S3.

[0036] During use, the user first sets the temperature and activates the pressurization mode. It determines whether the start-up water flow rate is reached based on the water flow rate detected by the water flow sensor in real time. If so, it starts the ignition and activates the water pump. During use, the water flow sensor continuously detects the water flow rate in real time. When the water flow rate is less than the shutdown water flow rate, it shuts down the water pump and turns off the fire; when the water flow rate is not less than the shutdown water flow rate, it determines whether the water temperature rise within a unit time is greater than the pump shutdown temperature difference △T 关泵 , if not, it maintains the operation of the pressurization function; if so, it shuts down the water pump and checks whether the water flow rate is less than the shutdown water flow rate. If so, it shuts down the fire; if not, it restarts the water pump and maintains the operation of the pressurization function. In the pressurization mode with a recirculating water pipeline, after the water is turned off, by monitoring the water temperature rise in the return water, it realizes a quick pump shutdown action, saving gas and electricity consumption and preventing the water temperature from being too hot when using water again; the pump shutdown temperature difference is adaptive according to the difference between the set temperature and the inlet water temperature, achieving intelligent recognition and meeting the different water temperature requirements in all seasons.

[0037] In step S4 of the present invention, the water temperature rise within a unit time is determined according to the formula water temperature rise = T 进 -T′ 进 to determine, where T 进 is the inlet water temperature measured in real time by the temperature probe, and T′ 进 is the inlet water temperature measured before the unit time. The unit time is generally 20s to 60s.

[0038] The pump shutdown temperature difference △T of the present invention 关泵 has a proportional linear relationship with the heating temperature difference △T 加热 . The higher the heating temperature difference △T 加热 , the larger the pump shutdown temperature difference △T 关泵 follows, adapting to different bathing water temperatures throughout the year. For example, in summer, the ambient temperature and the inlet water temperature are relatively high, and the user sets a relatively low bathing temperature. The heating temperature difference △T 加热 is small, matching a small pump shutdown temperature difference △T 关泵 , realizing a quick pump shutdown after the water is turned off while avoiding mis-pump shutdown due to the relatively high inlet water temperature; in winter, the ambient temperature and the inlet water temperature are relatively low, and the user sets a relatively high bathing temperature. The heating temperature difference △T 加热 is large, matching a large pump shutdown temperature difference △T 关泵 , realizing a quick pump shutdown after the water is turned off, reducing unnecessary gas and electricity consumption, and also reducing user misunderstandings. The heating temperature difference △T 加热 is determined according to the formula △T 加热＝ T 设 -T 进 to determine, where T 设 is the set temperature, and T 进 is the inlet water temperature measured in real time by the temperature probe.

[0039] The pump shutdown temperature difference △T of the present invention关泵 Determined according to the following formula:

[0040] When △T 加热 <△T 加热min , △T 关泵 =△T 关泵min ;

[0041] When △T 加热min ≤△T 加热 ≤△T 加热max , △T 关泵 =(△T 关泵max -△T 关泵min )*(△T 加热 -△T 加热min ) / (△T 加热max -△T 加热min )+△T 关泵min ;

[0042] When △T 加热 >△T 加热max , △T 关泵 =△T 关泵max ;

[0043] In the formula, △T 加热min is the minimum heating temperature difference set by the program, △T 加热max is the maximum heating temperature difference set by the program, △T 关泵min is the minimum pump shutdown temperature difference, △T 关泵max is the maximum pump shutdown temperature difference, △T 加热min corresponds to △T 关泵min , △T 加热max corresponds to △T 关泵max .

[0044] The minimum heating temperature difference △T 加热min set by the program, the maximum heating temperature difference △T 加热max set by the program, the minimum pump shutdown temperature difference △T 关泵min and the maximum pump shutdown temperature difference △T 关泵max are all fixed values or set according to the parameter setting method of the controller.

[0045] The pump shutdown temperature difference △T 关泵 of the present invention is a fixed value or set according to the parameter setting method of the controller, and the pump shutdown temperature difference △T 关泵 is a fixed value, generally 5°C to 10°C.

[0046] Such as Figure 3As shown in the figure, a gas water heater includes a gas water heater body 1, a temperature probe 2 provided at the water inlet end of the main water path of the gas water heater body 1, an operation display 3 provided on the gas water heater body 1, a water pump 4 and a water flow sensor 5 respectively provided on the main water path of the gas water heater body 1, and a controller 6 provided inside the gas water heater body 1. The controller 6 is electrically connected to the temperature probe 2, the operation display 3, the water pump 4 and the water flow sensor 5 respectively. The operation display 3 is provided with a temperature increase key and a temperature decrease key for temperature setting, a preheating key for turning on the preheating cycle function, and a pressurization key for turning on the pressurization function. The pipeline of the preheating cycle function of the gas water heater body 1 includes: a return pipe 7 provided between the external hot water pipe and the external cold water pipe outside the gas water heater body 1. By providing the return pipe 7, the water path of the gas water heater body 1 can form a circulation loop, so as to realize circulation preheating through the water pump 4. A one-way valve 8 for preventing the external cold water pipe from flowing back to the external hot water pipe is provided on the return pipe 7. The controller 6 at least has the control method for the gas water heater pressurization function as described above.

[0047] The above specific embodiments have detailed the technical solutions and beneficial effects of the present invention. It should be understood that the above is only the most preferred embodiment of the present invention and is not used to limit the present invention. Any modifications, supplements, equivalent replacements, etc. made within the scope of the principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A control method for the pressurization function of a gas water heater, including a controller, a temperature probe arranged at the water inlet end of the main water path of the gas water heater, and a water pump and a water flow sensor respectively arranged on the main water path of the gas water heater. Characterized in that, The control method includes the following steps: S1: Start the pressurization function; S2: Judge whether the water flow detected by the water flow sensor is greater than or equal to the startup water flow. If so, ignite and start up and turn on the water pump; if not, return to step S1; S3: Judge whether the water flow detected by the water flow sensor in real time is less than the shutdown water flow. If so, shut down and extinguish the fire and turn off the water pump; if not, enter step S4: S4: Detect the inlet water temperature in real time according to the temperature probe, and judge whether the water temperature rise per unit time is greater than the pump shutdown temperature difference △Tshut - off pump. If not, maintain the operation of the pressurization function and return to step S3; if so, turn off the water pump and enter step S5; S5: Judge whether the water flow detected by the water flow sensor is less than the shutdown water flow. If so, shut down and extinguish the fire; if not, restart the water pump, maintain the operation of the pressurization function and return to step S3; In step S4, the water temperature rise per unit time is determined according to the formula water temperature rise = Tin - T'in, where Tin is the inlet water temperature measured in real time by the temperature probe, and T'in is the inlet water temperature measured one unit time ago; The pump shutdown temperature difference △Tshut - off pump has a proportional linear relationship with the heating temperature difference △Theating. The heating temperature difference △Theating is determined according to the formula △Theating = Tset - Tin, where Tset is the set temperature and Tin is the inlet water temperature measured in real time by the temperature probe; The pump shutdown temperature difference △Tshut - off pump is determined according to the following formula: When △Theating < △Theating min, △Tshut - off pump = △Tshut - off pump min; When △Theating min ≤ △Theating ≤ △Theating max, △Tshut - off pump = (△Tshut - off pump max - △Tshut - off pump min) * (△Theating - △Theating min) / (△Theating max - △Theating min) + △Tshut - off pump min; When △Theating > △Theating max, △Tshut - off pump = △Tshut - off pump max; In the formula, △Theating min is the minimum heating temperature difference set by the program, △Theating max is the maximum heating temperature difference set by the program, △Tshut - off pump min is the minimum pump shutdown temperature difference, and △Tshut - off pump max is the maximum pump shutdown temperature difference.

2. The control method for the pressurization function of a gas water heater according to claim 1, Characterized in that, The minimum heating temperature difference △Theating min set by the program, the maximum heating temperature difference △Theating max set by the program, the minimum pump shutdown temperature difference △Tshut - off pump min and the maximum pump shutdown temperature difference △Tshut - off pump max are all fixed values or set according to the parameter setting method of the controller.

3. The control method for the pressurization function of a gas water heater according to claim 1, Characterized in that, The pump shutdown temperature difference △Tshut - off pump is a fixed value or set according to the parameter setting method of the controller.

4. A gas water heater, comprising a gas water heater body (1), a temperature probe (2) arranged at the water inlet end of the main water path of the gas water heater body (1), an operation display (3) arranged on the gas water heater body (1), a water pump (4) and a water flow sensor (5) respectively arranged on the main water path of the gas water heater body (1), and a controller (6) arranged inside the gas water heater body (1), wherein the controller (6) is electrically connected to the temperature probe (2), the operation display (3), the water pump (4) and the water flow sensor (5) respectively. It is characterized in that the controller (6) at least has the control method of the gas water heater boosting function as described in any one of claims 1 to 3.

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