A preheating and heat preservation control method for a zero-cold-water gas water heater

Abstract

The present invention discloses a preheating and heat preservation control method for a zero-cold-water gas water heater, which is characterized in that the control method comprises the following steps: S1, the gas water heater is in a standby mode; S2, controlling the gas water heater to enter a preheating working mode; S3, judging whether the return water temperature is greater than the difference between a preset temperature and a preheating temperature difference, if so, entering step S4, if not, maintaining the preheating working mode; S4, entering a preheating and heat preservation mode, and recording a real-time preheating pump-off water outlet temperature; S5, judging whether the water temperature drop is greater than the product of a heat preservation coefficient and a heat preservation temperature difference, if so, returning to step S2, if not, entering step S6; S6, judging whether the accumulated heat preservation time is greater than the program heat preservation time, if so, returning to step S1, if not, returning to step S5; the user experience can be improved.

Description

Technical Field

[0001] The invention relates to the technical field of water heaters, and in particular to a preheating and heat preservation control method for a zero-cold-water gas water heater, which is suitable for a domestic hot water supply gas water heater or a dual-purpose furnace. Background Art

[0002] In the related technologies, zero-cold-water gas water heaters have become a trend in the gas water heater industry because they can provide hot water immediately after it is turned on. When the existing gas water heaters start the preheating function, the built-in water pump drives the water in the hot water pipe and return pipe outside the machine to circulate and preheat. Some zero-cold-water gas water heaters on the market also have preheating and heat preservation functions. After preheating, they monitor the return water temperature for heat preservation. During the heat preservation period, the water temperature can be kept above a certain temperature value, ensuring that users can enjoy hot water immediately when they use water again, improving the comfort of hot water.

[0003] However, some existing zero-cold-water gas water heaters frequently turn on the water pump during the preheating and insulation process, which consumes too much gas and causes energy saving. It also makes the water temperature in the pipeline too high, affecting the water temperature comfort and providing users with a poor experience. Summary of the invention

[0004] The present invention aims to solve at least one of the problems existing in the existing related technologies to a certain extent. To this end, one purpose of the present invention is to propose a preheating and insulation control method for a zero-cold-water gas water heater, which can improve the user experience.

[0005] The above purpose is achieved through the following technical solutions:

[0006] A preheating and heat preservation control method for a zero-cold-water gas water heater, the control method comprising the following steps:

[0007] S1, the gas water heater is in standby mode;

[0008] S2, controls the gas water heater to enter the preheating working mode;

[0009] S3, determine whether the return water temperature is greater than the difference between the preset temperature and the preheating temperature difference, if so, proceed to step S4, if not, maintain the preheating working mode;

[0010] S4, enter the preheating and heat preservation mode, and record the real-time preheating pump shut-off water outlet temperature;

[0011] S5, determining whether the water temperature drop is greater than the product of the insulation coefficient and the insulation temperature difference, if so, returning to step S2, if not, proceeding to step S6;

[0012] S6, judging whether the accumulated insulation time is greater than the programmed insulation time, if so, returning to step S1, if not, returning to step S5.

[0013] In some embodiments, step S5 includes:

[0014] Determine whether the water temperature is less than the difference between the preset temperature and the insulation temperature difference. If so, return to step S2; if not, enter step S6.

[0015] In some embodiments, the insulation coefficient has a proportional linear relationship with the real-time preheating pump-off water outlet temperature.

[0016] In some embodiments, the insulation coefficient is determined as follows:

[0017] When the real-time preheating pump-off water outlet temperature is greater than the preset maximum preheating pump-off water outlet temperature, the insulation coefficient is equal to the preset maximum insulation coefficient;

[0018] When the real-time preheating pump-off water outlet temperature is lower than the preset minimum preheating pump-off water outlet temperature, the insulation coefficient is equal to the preset minimum insulation coefficient;

[0019] When the real-time preheating pump-off water outlet temperature is greater than the preset minimum preheating pump-off water outlet temperature and less than the preset maximum preheating pump-off water outlet temperature, the insulation coefficient is determined according to the following formula:

[0020] K=K min +(K max -K min )×(T 关出 -T 关出min ) / (T 关出max -T 关出min );

[0021] Where K min is the preset minimum insulation coefficient, K max is the preset maximum insulation coefficient, T 关出 The real-time preheating pump outlet water temperature, T 关出min is the preset minimum preheating pump shut-off water outlet temperature, T 关出max The preset maximum preheating pump shut-off water outlet temperature.

[0022] In some embodiments, the insulation coefficient has a proportional linear relationship with the real-time ambient temperature.

[0023] In some embodiments, the insulation coefficient is determined as follows:

[0024] When the real-time ambient temperature is greater than the preset maximum ambient temperature, the insulation coefficient is equal to the preset maximum insulation coefficient;

[0025] When the real-time ambient temperature is lower than the preset minimum ambient temperature, the insulation coefficient is equal to the preset minimum insulation coefficient;

[0026] When the real-time ambient temperature is greater than the preset minimum ambient temperature and less than the preset maximum ambient temperature, the insulation coefficient is determined according to the following formula:

[0027] K=K min +(K max -K min )×(T 环境 -T 环境min ) / (T 环境max -T 环境min );

[0028] Where K min is the preset minimum insulation coefficient, K max is the preset maximum insulation coefficient, T 环境 is the real-time ambient temperature, T 环境min is the preset minimum ambient temperature, T 环境max The preset maximum ambient temperature.

[0029] In some embodiments, the insulation coefficient is 0.1 to 5.

[0030] In some embodiments, the setting range of the insulation temperature difference is 3°C to 15°C.

[0031] In some embodiments, the incubation time is from 0 to 60 minutes.

[0032] Compared with the prior art, the present invention has at least the following beneficial effects:

[0033] 1. A preheating and heat preservation control method for a zero-cold-water gas water heater of the present invention can improve the user experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 is a schematic structural diagram of a zero cold water gas water heater according to an embodiment of the present invention;

[0035] Figure 2 1 is a flow chart of a preheating and heat preservation control method according to an embodiment of the present invention;

[0036] Figure 3 Schematic diagram of the relationship between the pipe water temperature and the temperature drop rate in an embodiment of the present invention;

[0037] Figure 4 Schematic diagram of the relationship between the preheating pump-off water outlet temperature and the insulation coefficient in an embodiment of the present invention;

[0038] Figure 5 Schematic diagram of the relationship between ambient temperature and thermal insulation coefficient in an embodiment of the present invention. DETAILED DESCRIPTION

[0039] The following examples illustrate the present invention, but the present invention is not limited to these examples. Modifications to the specific embodiments of the present invention or equivalent replacement of some technical features without departing from the spirit of the present invention should be included in the scope of the technical solution claimed by the present invention.

[0040] Embodiment 1: Figure 1 and Figure 2 As shown, this embodiment provides a preheating and heat preservation control method for a zero-cold-water gas water heater, wherein the zero-cold-water gas water heater comprises a gas water heater body 1, a water pump 2, an outlet water temperature probe 3, a return water temperature probe 4, a gas control valve 5, an operation display 6 and a controller 7, the water pump 2 is installed on the main waterway in the gas water heater body 1, the outlet water temperature probe 3 is installed at the outlet end of the main waterway of the gas water heater body 1 for real-time monitoring of the outlet water temperature, the return water temperature probe 4 is installed at the inlet end of the main waterway of the gas water heater body 1 for real-time monitoring of the return water temperature, the gas control valve 5 is installed on the gas supply passage in the gas water heater body 1 for controlling the opening and disconnection of the gas, and the operation display 6 is provided with a temperature setting key and a preheating function key. The water pump 2, the outlet water temperature probe 3, the return water temperature probe 4, the gas control valve 5 and the operation display 6 are all electrically connected to the controller 7. The controller 7 has a heat preservation timing function. During the preheating and heat preservation period, the controller 7 realizes preheating and heat preservation by monitoring the change of the outlet water temperature.

[0041] As a further illustration of the above solution, the temperature setting key of the operating display 6 can be used to set a preset temperature, and the preset temperature setting range is generally: 35°C to 60°C.

[0042] As a further illustration of the above solution, the preheating function key of the operating display 6 can turn the preheating function on and off.

[0043] As a further illustration of the above solution, the preheating function key of the operating display 6 can set the insulation temperature difference ΔT 保温 And insulation time, insulation temperature difference △T 保温 The setting range is generally from 3°C to 15°C, and the holding time setting range is generally from 0 to 60 minutes.

[0044] As a further illustration of the above scheme, a return pipe 8 is provided at the hot water faucet at the water use point to connect to the water inlet end of the gas water heater body 1, and a one-way valve 9 is provided on the return pipe 8 to prevent tap water from flowing directly to the hot water faucet. After the preheating function is started, the water in the pipeline is heated and flows into the hot water pipe from the water outlet end of the gas water heater body 1, and then flows back to the water inlet end of the gas water heater body 1 through the return pipe 8.

[0045] The preheating and heat preservation control method provided in this embodiment includes the following steps:

[0046] S1, the gas water heater is in standby mode;

[0047] S2, control the gas water heater to enter the preheating working mode. Specifically, the preheating function is started by operating the preheating function key of the display 6, the controller 7 turns on the water pump 2 and the gas control valve 5, starts the ignition to preheat the water in the pipeline, and enters the preheating working mode;

[0048] S3, determine the return water temperature T 回 Is it greater than the preset temperature T 预设 and preheating temperature difference △T 预设 If yes, then go to step S4, if no, then maintain the preheating mode. Specifically, when the return water temperature probe 4 measures the return water temperature T 回 Greater than the preset temperature T 预设 Subtract preheating temperature difference △T 预设 When, that is, T 回 >T 预设 -△T 预设 , the controller 7 turns off the water pump 2 and the gas control valve 5, turns off the flame, and switches to the preheating and heat preservation mode. The controller records the outlet water temperature when the pump is turned off and the flame is turned off, that is, the real-time preheating pump outlet water temperature T 关出 ;

[0049] S4, enter the preheating and heat preservation mode, and record the real-time preheating pump off water outlet temperature T 关出 ;

[0050] S5, determine the water temperature drop △T 关 Is it greater than the insulation coefficient K and the insulation temperature difference △T 保温 If yes, then return to step S2, if no, then go to step S6. Specifically, when the outlet water temperature probe 3 measures the water temperature drop △T 关 When it is greater than the product of the insulation coefficient K and the insulation temperature difference △T, that is, △T 关 =T 关出 -T 出 >K×△T 保温 When the temperature is too high, the controller 7 starts the water pump 2 and the gas control valve 5, and starts the ignition to preheat the water in the pipeline. The insulation coefficient K is a fixed value or is set by the parameter setting method of the controller. The value range of the insulation coefficient K is 0.1 to 5, and the preferred value range is 0.5 to 2.0;

[0051] S6, determine whether the cumulative insulation time is greater than the program insulation time. If so, return to step S1, if not, return to step S5. Specifically, when the controller 7 measures that the cumulative insulation time is greater than the program insulation time, it exits the preheating insulation mode and switches to the standby mode.

[0052] The present embodiment provides a preheating and insulation control method for a zero-cold-water gas water heater, which can improve the user experience. Specifically, it can extend the start time of the water pump during the insulation period, prevent the water pump from being frequently turned on for preheating and insulation, thereby achieving the purpose of saving gas and energy. It can also prevent the insulation water from being too hot, thereby improving the water use experience. The method is suitable for household hot water supply gas water heaters and dual-purpose furnaces.

[0053] In this embodiment, step S5 includes:

[0054] Determine the outlet water temperature T 出 Is it lower than the preset temperature T? 预设 Temperature difference with insulation △T 保温 If yes, then return to step S2, if no, then enter step S6, specifically, the gas water heater body is in the preheating and heat preservation mode, when the outlet water temperature probe 3 measures the outlet water temperature T 出 Less than the preset temperature T 预设 Subtract the insulation temperature difference △T 保温 When, that is, T 出 <T 预设 -△T 保温 As a supplement to the above-mentioned water outlet temperature reduction and heat preservation control scheme, the present invention also controls the heat preservation start water pump by monitoring the difference between the water outlet temperature and the preset temperature, which can prevent the water temperature in the pipeline from being too low and affecting the hot water experience during the heat preservation period.

[0055] As a further illustration of the above scheme, Figure 3 As shown in the figure, it is a temperature drop rate curve of the water temperature in the pipeline. The higher the water temperature, the faster the temperature drop rate. The controller 7 preheats the pump according to the real-time water outlet temperature T 关出 Automatically match a thermal insulation coefficient K, and the matched thermal insulation coefficient K is consistent with the real-time preheating pump off water outlet temperature T 关出 There is a proportional linear relationship. When the real-time preheating pump outlet water temperature T 关出 When it is higher, a larger insulation coefficient K is matched to extend the insulation pump start time, and the water in the pipeline will not be overcooled during the insulation period, achieving energy saving and gas saving effects. One of the better determination methods is as follows:

[0056] like Figure 4 As shown, the preset minimum preheating pump shut-off water outlet temperature T 关出min Corresponding to the preset minimum insulation coefficient K min , preset the maximum preheating pump off water outlet temperature T 关出max Corresponding to the preset maximum insulation coefficient K max ; Preset minimum preheating pump shut-off water outlet temperature T 关出min , preset the maximum preheating pump off water outlet temperature T 关出max , preset maximum insulation coefficient K maxAnd preset minimum insulation coefficient K min All are fixed values ​​or set by the controller parameter setting method. Preset minimum preheating pump off water outlet temperature T 关出min Generally, it is 35℃, and the preset maximum preheating pump shut-off water outlet temperature is T 关出max Generally it is 50℃.

[0057] In this embodiment, the thermal insulation coefficient K is determined as follows:

[0058] When the real-time preheating pump is turned off, the outlet water temperature T 关出 Greater than the preset maximum preheating pump shut-off water outlet temperature T 关出max When the insulation coefficient K is equal to the preset maximum insulation coefficient K max ;

[0059] When the real-time preheating pump is turned off, the outlet water temperature T 关出 Less than the preset minimum preheating pump shut-off water outlet temperature T 关出min When the insulation coefficient K is equal to the preset minimum insulation coefficient K min ;

[0060] When the real-time preheating pump is turned off, the outlet water temperature T 关出 Greater than the preset minimum preheating pump shut-off water outlet temperature T 关出min And it is less than the preset maximum preheating pump shut-off water outlet temperature T 关出max When the insulation coefficient K is determined by the following formula:

[0061] K=K min +(K max -K min )×(T 关出 -T 关出min ) / (T 关出max -T 关出min );

[0062] Where K min is the preset minimum insulation coefficient, K max is the preset maximum insulation coefficient, T 关出 The real-time preheating pump outlet water temperature, T 关出min is the preset minimum preheating pump shut-off water outlet temperature, T 关出max The preset maximum preheating pump shut-off water outlet temperature.

[0063] like Figure 5 As shown, the preset minimum ambient temperature T 环境min Corresponding to the preset minimum insulation coefficient K min , preset maximum ambient temperature T 环境max Corresponding to the preset maximum insulation coefficient K max ; Preset minimum ambient temperature T 环境min , preset maximum ambient temperature T 环境max , preset maximum insulation coefficient Kmax And preset minimum insulation coefficient K min All are fixed values ​​or set by the parameter setting method of the controller 7. The program presets the minimum ambient temperature T 环境min Generally, it is 5℃, and the program presets the maximum ambient temperature T 环境max Generally, it is 30℃, and the insulation coefficient K is related to the real-time ambient temperature T 环境 There is a proportional linear relationship.

[0064] In this embodiment, the thermal insulation coefficient K is determined as follows:

[0065] When the real-time ambient temperature T 环境 Greater than the preset maximum ambient temperature T 环境max When the insulation coefficient K is equal to the preset maximum insulation coefficient K max ;

[0066] When the real-time ambient temperature T 环境 Lower than the preset minimum ambient temperature T 环境min When the insulation coefficient K is equal to the preset minimum insulation coefficient K min ;

[0067] When the real-time ambient temperature T 环境 Greater than the preset minimum ambient temperature T 环境min And is less than the preset maximum ambient temperature T 环境max When the insulation coefficient K is determined by the following formula:

[0068] K=K min +(K max -K min )×(T 环境 -T 环境min ) / (T 环境max -T 环境min );

[0069] Where K min is the preset minimum insulation coefficient, K max is the preset maximum insulation coefficient, T 环境 is the real-time ambient temperature, T 环境min is the preset minimum ambient temperature, T 环境max The preset maximum ambient temperature.

[0070] The preheating and heat preservation control method of this embodiment realizes the heat preservation function according to the change of the outlet water temperature in its preheating and heat preservation mode, which can extend the heat preservation pump start time, prevent the heat preservation pump from being started frequently, save energy and gas, and improve the water temperature comfort.

[0071] In addition, the insulation time is automatically adjusted by the preheating pump water outlet temperature or ambient temperature to meet the preheating water temperature or preheating insulation requirements in different seasons, reflecting the intelligence of the product.

[0072] The above are only some embodiments of the present invention. For those skilled in the art, several modifications and improvements can be made without departing from the creative concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A preheating and heat preservation control method for a zero-cold-water gas water heater, characterized in that: The control method comprises the following steps: S1, the gas water heater is in standby mode; S2, controls the gas water heater to enter the preheating working mode; S3, determine whether the return water temperature is greater than the difference between the preset temperature and the preheating temperature difference, if so, proceed to step S4, if not, maintain the preheating working mode; S4, enter the preheating and heat preservation mode, and record the real-time preheating pump shut-off water outlet temperature; S5, determining whether the water temperature drop is greater than the product of the insulation coefficient and the insulation temperature difference, if so, returning to step S2, if not, proceeding to step S6; S6, determining whether the accumulated insulation time is greater than the programmed insulation time, if so, returning to step S1, if not, returning to step S5; The insulation coefficient has a proportional linear relationship with the real-time preheating pump shut-off water outlet temperature. The insulation coefficient is determined as follows: When the real-time preheating pump-off water outlet temperature is greater than the preset maximum preheating pump-off water outlet temperature, the insulation coefficient is equal to the preset maximum insulation coefficient; When the real-time preheating pump-off water outlet temperature is lower than the preset minimum preheating pump-off water outlet temperature, the insulation coefficient is equal to the preset minimum insulation coefficient; When the real-time preheating pump-off water outlet temperature is greater than the preset minimum preheating pump-off water outlet temperature and less than the preset maximum preheating pump-off water outlet temperature, the insulation coefficient is determined according to the following formula: K = Kmin + (Kmax - Kmin) × (Toff - Toffmin) / (Toffmax - Toffmin); Where Kmin is the preset minimum insulation coefficient, Kmax is the preset maximum insulation coefficient, Tshunt is the real-time preheating pump-off water outlet temperature, Tshuntmin is the preset minimum preheating pump-off water outlet temperature, and Tshuntmax is the preset maximum preheating pump-off water outlet temperature; or The insulation coefficient has a proportional linear relationship with the real-time ambient temperature and is determined as follows: When the real-time ambient temperature is greater than the preset maximum ambient temperature, the insulation coefficient is equal to the preset maximum insulation coefficient; When the real-time ambient temperature is lower than the preset minimum ambient temperature, the insulation coefficient is equal to the preset minimum insulation coefficient; When the real-time ambient temperature is greater than the preset minimum ambient temperature and less than the preset maximum ambient temperature, the insulation coefficient is determined according to the following formula: K = Kmin + (Kmax - Kmin) × (Tenvironment - Tenvironmentmin) / (Tenvironmentmax - Tenvironmentmin); Wherein Kmin is the preset minimum insulation coefficient, Kmax is the preset maximum insulation coefficient, Tenvironment is the real-time ambient temperature, Tenvironmentmin is the preset minimum ambient temperature, and Tenvironmentmax is the preset maximum ambient temperature.

2. A preheating and heat preservation control method for a zero-cold-water gas water heater according to claim 1, characterized in that: Step S5 comprises: Determine whether the water temperature is less than the difference between the preset temperature and the insulation temperature difference. If so, return to step S2; if not, enter step S6.

3. A preheating and heat preservation control method for a zero-cold-water gas water heater according to claim 1 or 2, characterized in that: The thermal insulation coefficient is 0.1 to 5.

4. A preheating and heat preservation control method for a zero-cold-water gas water heater according to claim 1 or 2, characterized in that: The setting range of the insulation temperature difference is 3℃ to 15℃.

5. A preheating and heat preservation control method for a zero-cold-water gas water heater according to claim 1 or 2, characterized in that: The holding time is from 0 to 60 minutes.

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