CN112344425A - Gas heating equipment, heating and hot water supplying system and control method thereof - Google Patents
Gas heating equipment, heating and hot water supplying system and control method thereof Download PDFInfo
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- CN112344425A CN112344425A CN201910726131.0A CN201910726131A CN112344425A CN 112344425 A CN112344425 A CN 112344425A CN 201910726131 A CN201910726131 A CN 201910726131A CN 112344425 A CN112344425 A CN 112344425A
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24D—DOMESTIC- OR SPACE-HEATING SYSTEMS, e.g. CENTRAL HEATING SYSTEMS; DOMESTIC HOT-WATER SUPPLY SYSTEMS; ELEMENTS OR COMPONENTS THEREFOR
- F24D15/00—Other domestic- or space-heating systems
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24D—DOMESTIC- OR SPACE-HEATING SYSTEMS, e.g. CENTRAL HEATING SYSTEMS; DOMESTIC HOT-WATER SUPPLY SYSTEMS; ELEMENTS OR COMPONENTS THEREFOR
- F24D19/00—Details
- F24D19/10—Arrangement or mounting of control or safety devices
- F24D19/1006—Arrangement or mounting of control or safety devices for water heating systems
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- Steam Or Hot-Water Central Heating Systems (AREA)
- Heat-Pump Type And Storage Water Heaters (AREA)
Abstract
The invention discloses gas heating equipment, a heating and hot water supplying system and a control method thereof. The gas heating apparatus includes: the heating water outlet joint, the heating water return joint, the water inlet joint, the zero cold water joint and the hot water joint are arranged on the shell; the hot water supply assembly comprises a water tank and a water pump, and the water pump is connected with the water tank; the water outlet switching valve is used for controlling the main water outlet to be selectively connected with a water tank or a heating water outlet joint; the water inlet switching valve and the water outlet switching valve are used for controlling the selective connection of the total water inlet with a water inlet joint or a heating water return joint; the circulating pump is connected between the water inlet switching valve and the main water inlet; wherein, the hot water joint is connected with the water tank, and the zero cold water joint is connected with the water pump. The water tank is used for heating the stored water in the external water pipe, so that the gas consumption is saved, and the water use experience of a user is improved.
Description
Technical Field
The invention belongs to the technical field of heating furnaces, and particularly relates to a gas heating device, a heating hot water supply system and a control method thereof.
Background
At present, gas heating equipment adopts gas as energy to heat water to realize heating, and along with the improvement of the technology, the gas heating equipment can also have the function of supplying domestic hot water for users. For example: chinese patent application No. 201811537311.6 discloses a zero-cold water gas wall-mounted boiler system which can meet the heating requirement in a room on one hand and can also meet the zero-cold water hot water supply on the other hand. However, in the actual use process, in order to realize zero cold water, the cold water in the water outlet pipe needs to be conveyed to the gas furnace from the water return pipe through the water pump for heating, and then conveyed to the water outlet pipe again. However, because the water quantity stored in the water outlet pipe is small, when the water is heated by burning of the gas furnace, the heat generated by burning and heating is far greater than the requirement of the stored water quantity under the influence of the minimum heating power of the gas furnace, and the starting and stopping of the burner of the gas furnace are controlled by detecting whether the heating temperature reaches a set value or not. In the actual use process, in order to keep the temperature of water in a water pipe, the water in the pipe needs to be heated, when the water temperature reaches the preset temperature, the machine does not work, when the water temperature is lower than the preset water temperature, the water pump needs to be ignited again for heating, the water pump is restarted for running, the machine is started repeatedly, the service life of the gas furnace is influenced, and the waste of gas is caused by frequent starting; because the amount of the zero-cold water is small, the temperature is easy to exceed the temperature when the water is heated by combustion, and the temperature difference between the zero-cold water and the temperature to be used is large (suddenly cold and suddenly hot) in the use process of a user, so that uncomfortable water using experience is caused. The invention aims to solve the technical problem of how to design a technology for saving gas consumption and improving water use experience of a user.
Disclosure of Invention
The invention provides a gas heating device, a heating and hot water supplying system and a control method thereof, aiming at the technical problems in the prior art, in the zero cold water heating process, water stored in an external water pipe is heated or buffered by a water tank, so that the starting and stopping times of a gas furnace are reduced, the fluctuation of the outlet water temperature is reduced, the gas consumption is saved, and the water use experience of a user is improved.
In order to realize the purpose of the invention, the invention is realized by adopting the following technical scheme:
the present invention provides a gas heating apparatus, comprising:
the heating water outlet joint, the heating water return joint, the water inlet joint, the zero cold water joint and the hot water joint are arranged on the shell;
the gas furnace is provided with a main water outlet and a main water inlet;
the hot water supply assembly comprises a water tank and a water pump, and the water pump is connected with the water tank;
the water outlet switching valve is used for controlling the main water outlet to be selectively connected with the water tank or the heating water outlet joint;
the water inlet switching valve is used for controlling the main water inlet to be selectively connected with the water inlet connector or the heating water return connector;
the circulating pump is connected between the water inlet switching valve and the main water inlet;
wherein, hot water connects with the water tank is connected, zero cold water connects with the water pump is connected.
Further, the water tank is provided with a first water port, a second water port and a third water port; the first water port is connected with the hot water joint, the second water port is connected with the water outlet switching valve, and the third water port is respectively connected with the water inlet switching valve and the water inlet joint.
Further, the water pump is connected with the second water gap or the third water gap.
Furthermore, a one-way valve is arranged between the zero cold water joint and the water tank.
Furthermore, a plurality of hanging jacks are formed in the side wall of the shell, a first inserting tongue and a fixing support are arranged on the gas furnace, a hanging frame is arranged on the water tank, a second inserting tongue is formed in the hanging frame, the first inserting tongue and the second inserting tongue are respectively inserted into the corresponding hanging jacks, and the fixing support and the hanging frame are fixed on the shell through screws.
Further, the water tank includes:
the heat preservation tank is internally provided with a water storage cavity;
the hot water outlet pipe is inserted into the heat-preserving tank, and a pipe orifice of the hot water outlet pipe, which is positioned outside the heat-preserving tank, forms the first water gap;
the circulating water pipe is inserted into the heat-preserving tank, and a pipe orifice of the circulating water pipe positioned outside the heat-preserving tank forms the second water port;
and the water inlet and outlet pipe is inserted into the heat-insulating tank, and the pipe orifice of the water inlet and outlet pipe, which is positioned outside the heat-insulating tank, forms the third water port.
Further, the bottom of the heat-preserving tank is provided with a mounting opening; the water tank further comprises a sealing cover, the sealing cover is connected to the mounting opening in a sealing mode, and the hot water outlet pipe, the circulating water pipe and the water inlet and outlet pipe penetrate through the sealing cover in a sealing mode.
Furthermore, a first expansion tank is connected to the water tank, and a second expansion tank is connected to a pipeline between the heating water return joint and the main water inlet.
The invention also provides a heating and hot water supply system, which comprises a hot water output terminal, a heat dissipation terminal and the gas heating equipment; and a heating water outlet joint and a heating water return joint of the gas heating equipment are respectively connected with the heat dissipation terminal.
The invention also provides a control method of the heating and hot water supply system, which comprises the following steps: executing a zero cold water heating mode;
in the zero cold water heating mode, water flowing in through the zero cold water joint enters the water tank, is mixed with water in the water tank and then is output from the hot water joint.
Compared with the prior art, the invention has the advantages and positive effects that: by adding the water tank, hot water stored in the water tank is used for conveying domestic hot water to the outside, and when zero cold water is heated, water in the external water pipe enters the water tank through the zero cold water joint, so that the water in the external water pipe is mixed with the hot water stored in the water tank, the effect of reducing the switching times of the gas furnace can be achieved, the gas consumption is saved, and the service life is prolonged; the zero cold water heating process is realized by utilizing the water in the water tank, the condition that a user is scalded by high water temperature due to the fact that zero cold water is output by direct heating is avoided, and the user experience is improved.
Other features and advantages of the present invention will become more apparent from the following detailed description of the invention when taken in conjunction with the accompanying drawings.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.
FIG. 1 is a schematic view of a schematic structure of an embodiment of a gas heating apparatus according to the present invention;
FIG. 2 is a schematic view showing the structure of an embodiment of the gas heating apparatus according to the present invention;
FIG. 3 is a schematic view of a gas heating apparatus according to an embodiment of the present invention with an outer case removed;
FIG. 4 is a schematic view showing a structure of a water tank in an embodiment of the gas heating apparatus of the present invention;
FIG. 5 is a schematic structural view of a water inlet and outlet pipe group in an embodiment of the gas heating apparatus of the present invention;
FIG. 6 is a schematic diagram illustrating the structure of a heating and hot water supply system according to the present invention;
FIG. 7 is a flow chart of the present invention for performing a domestic hot water heating mode;
FIG. 8 is a control flow chart of a heating and hot water supply system in a bathing mode;
FIG. 9 is a flow chart of the present invention for implementing a zero cold water heating mode.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail with reference to the accompanying drawings and examples.
It should be noted that in the description of the present invention, the terms of direction or positional relationship indicated by the terms "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, which are merely for convenience of description, and do not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
As shown in fig. 1 to 5, the gas heating apparatus of the present embodiment includes: the device comprises a shell 2, a gas furnace 1, a hot water supply assembly 3, a circulating pump 4, a water outlet switching valve 5 and a water inlet switching valve 6.
The shell 2 is provided with a heating water outlet joint 21, a heating water return joint 22, a water inlet joint 23, a zero cold water joint 24 and a hot water joint 25. Specifically, the water inlet connector 23 may be connected to an external water supply source (e.g., a tap water pipe) to introduce new cold water; the heating water outlet joint 21 and the heating water return joint 22 are connected with an external heat dissipation terminal to realize the circulating flow of heating water; the hot water joint 25 is used for delivering domestic hot water to the outside.
The gas furnace 1 is provided with a main water outlet 11 and a main water inlet 12, and the gas furnace 1 is used for burning gas to heat water input from the main water inlet 12 and output hot water from the main water outlet 11. The gas stove 1 is also provided with a burner 13, a heat exchanger 14 and other components, the water is input into the heat exchanger 14 from the main water inlet 12, the burner 13 can heat the water in the heat exchanger 14 by burning gas, and the water heated by the heat exchanger 14 is output through the main water outlet 11. Here, the specific configuration of the gas furnace 1 will not be described in detail. The heating water outlet joint 21 is used for delivering the hot water output from the main water outlet 11 to a heat dissipation terminal (for example, a ground heating pipe or a radiator) arranged in a user room, and the water output from the heat dissipation terminal flows back to the heat exchanger 14 through the heating water return joint 22.
The hot water supply unit 3 is provided with a water tank 31 and a water pump 32. Specifically, the hot water in the water tank 31 is delivered to the outside through the hot water joint 25, and the hot water delivered from the hot water joint 25 is delivered to a hot water delivery terminal (for example, a shower head or a hot water faucet) through a water supply pipe disposed in the home of the user. The water return pipe connected to the water supply pipe for realizing the zero-cold-water function is connected to the zero-cold-water joint 24, and the specific connection mode between the water supply pipe and the water return pipe is not limited or described herein, referring to the gas water heating device with the zero-cold-water function in the conventional technology.
The water outlet switching valve 5 is used for controlling the main water outlet 11 to be selectively connected with the water tank 31 or the heating water outlet joint 21;
the water inlet switching valve 6 is used for controlling the main water inlet 11 to be selectively connected with a water inlet joint 23 or a heating water return joint 22.
The circulating pump 4 is connected between the water inlet switching valve 6 and the main water inlet 12;
wherein, the hot water joint 25 is connected with the water tank 31, and the zero cold water joint 24 is connected with the water pump 32.
Specifically, the burner 13 in the gas stove 1 heats the water in the heat exchanger 14 and outputs the water through the main water outlet 11. The hot water output from the main water outlet 11 can be directly delivered to the heating water outlet joint 21 for heating, and the hot water output from the main water outlet 11 can also be delivered to the water tank 31. The hot water in the water tank 31 can be output to the outside through the hot water joint 25 to supply domestic hot water. The zero cold water junction 24 can input cold water in a water supply pipe and a water return pipe into the water tank 31 through the water pump 32 to perform a function of zero cold water by mixing hot water in the water tank 31 with cold water. For the circulation pump 4, in the heating water heating process, the circulation pump 4 pumps the heating water in the external heat radiation terminal into the gas furnace 1 through the heating water return joint 22, and the heating water heated by the gas furnace 1 is delivered back to the heat radiation terminal through the heating water outlet joint 21. And after cold water introduced by the water inlet joint 23 enters the gas furnace 1 to be heated, hot water output from the main water outlet 11 enters the water tank 31.
The water tank 31 is connected with a first expansion tank 71, a pipeline between the heating water return joint 22 and the main water inlet 11 is also connected with a second expansion tank 72, and the first expansion tank 71 can meet the volume change of water in the water tank 31 caused by expansion with heat and contraction with cold in the heating process; similarly, the second expansion tank 72 can satisfy the volume change of the heating pipeline caused by the expansion and contraction of the heating water body.
In addition, as the gas stove 1 and the water tank 31 are arranged in the housing 1, for convenience of assembly and installation at home of later users, a plurality of hanging jacks 201 are arranged on the side wall of the housing 2, a first inserting tongue 101 and a fixing bracket 102 are arranged on the gas stove 1, the water tank 31 is provided with a hanging frame 3101, a second inserting tongue 3102 is formed on the hanging frame 3101, the first inserting tongue 101 and the second inserting tongue 3102 are respectively inserted into the corresponding hanging jacks 201, and the fixing bracket 102 and the hanging frame 3101 are fixed on the housing 2 through screws. Specifically, in the assembly stage of a factory, the gas furnace 1 and the water tank 31 are hung on the back plate of the housing 1 through corresponding inserting tongues, so that the rapid positioning and assembly on site are facilitated; then, the gas burner 1 and the water tank 31 are firmly fixed to the housing 1 by screws to complete the assembly of the whole apparatus. When the casing 1 is installed and used in the home of a later user, the casing only needs to be installed in the home of the user integrally to realize one-time integral installation.
Further, the water tank 31 has a first water port (not marked), a second water port (not marked) and a third water port (not marked), the first water port is connected to the hot water connector 25, the second water port is connected to the outlet switching valve 5, and the third water port is connected to the inlet connector 23 and the inlet switching valve 6, respectively. Specifically, during the normal domestic hot water supply process, the hot water in the water tank 31 is output through the first water port and flows to the hot water joint 25 to realize the external domestic hot water supply, and when the water tank 31 supplies the domestic hot water to the outside, the water supplied from the external water source is input into the water tank 31 through the water inlet joint 23 to realize the pressing out of the hot water stored in the water tank 31. When the hot water in the water tank 31 is insufficient, the cold water introduced by the water inlet joint 23 firstly enters the gas furnace 1 through the water inlet switching valve 6 to be heated, and then enters the water tank 31 from the second water port, and the hot water in the water tank 31 passes through the hot water joint 25 to be output to the outside as the domestic hot water. In the zero cold water mode, the water pump 32 is activated to pump the water stored in the external water pipe from the zero cold water joint 24 into the water tank 31 and mix the water with the hot water in the water tank 31 to perform the zero cold water function. The water pump 32 may be connected to the second water port of the water tank 31, or may be connected to the third water port of the water tank 31. In order to avoid the water from being reversely output from the zero-cold water joint 24 during use, a check valve 321 is further disposed between the zero-cold water joint 24 and the water tank 31, the check valve 321 is used for controlling the water flowing out from the zero-cold water joint 24 to flow into the water tank 31 in a one-way manner, and the check valve 321 may be installed at an inlet or an outlet of the water pump 32.
When water is needed for heating, the water outlet switching valve 5 is switched to enable the main water outlet 11 to be communicated with the heating water outlet joint 21, so that high-temperature water output by the main water outlet 11 is directly conveyed to a heat dissipation terminal through the heating water outlet joint 21; meanwhile, the water inlet switching valve 6 is switched to enable the main water inlet 12 to be communicated with the heating water return joint 22, and heating water enters the main water inlet 12 through the heating water return joint 22 after being radiated by the radiating terminal so as to be heated through the gas furnace 1.
When domestic hot water needs to be heated, the water outlet switching valve 5 is switched to enable the main water outlet 11 to be communicated with the water tank 31, and the main water inlet 12 can be switched to be communicated with the water inlet connector 23 and the water tank 31 through the water inlet switching valve 6. When the external water source of the water inlet joint 23 is closed and the circulating pump 4 is started, the water in the water tank 31 can be circulated to the gas stove 1 for heating. When the water inlet joint 23 is provided with an external water source, the circulating pump 4 is started to guide cold water introduced by the water inlet joint 23 to enter the water tank 31 after being heated by the gas stove 1.
In actual use, the gas heating apparatus includes: a tank water supply mode and an instant heating water supply mode. In the tank water supply mode, if the temperature sensor in the tank 31 detects that the temperature of water in the tank 31 is higher than a set temperature, the water inlet switching valve 6 cuts off the flow path between the total water inlet 12 and the tank 31, and when the user uses hot water, cold water output from the water inlet joint 23 directly enters the tank 31, hot water in the tank 31 is squeezed out, and the hot water is output from the hot water joint 25. In the process of using water, when the temperature sensor in the water tank 31 detects that the temperature of the water tank 31 is lower than the set temperature, the instant hot water supply mode is started. Under the instant water supply mode, the water outlet switching valve 5 is switched to enable the main water outlet 11 to be communicated with the water tank 31, the water inlet switching valve 6 is switched to enable the main water inlet 12 to be communicated with the water tank 31, the gas furnace 1 and the circulating pump 4 are started simultaneously, and under the action of the circulating pump 4, water output by the water inlet joint 23 enters the gas furnace 1 to be heated and then enters the water tank 31 and is output from the hot water joint 25, so that instant water supply is realized; meanwhile, under the water inlet pressure of the water inlet joint 23, the water in the water tank 31 can be prevented from being output from the third water port.
When the user does not use hot water, the water stored in the water tank 31 needs to be heated, and in this case, in order to ensure that the water in the water tank 31 can be circulated into the heat exchanger 4 and to prevent the external water from entering through the water inlet joint 23, the water inlet joint 23 may be provided with a control valve 231. When it is necessary to heat the water in the water tank 31, the water inlet joint 23 is closed by the control valve 231 and then the gas furnace 1 and the circulation pump 4 are started. The water in the water tank 31 is conveyed into the gas furnace 1 to be heated and then returns to the water tank 31, the combustion and heating are stopped until the water in the water tank 31 reaches the set temperature, the whole machine enters a standby state, and meanwhile, the heat of the water tank 31 is preserved.
The specific process of the gas furnace 1 for heating water and supplying the water to the heating assembly 2 for outputting hot water refers to a gas heating furnace of the conventional technology, and is not limited and described herein. The specific process of the gas furnace 1 in the process of heating the domestic water of the user is as follows: in the zero-cold-water mode, when the temperature of water in the water supply pipe is lower than the set temperature, the zero-cold-water heating function is started, and at this time, under the action of the water pump 32, water in the water supply pipe enters the water tank 31 through the zero-cold-water joint 24 to circularly flow until the temperature of water in the water supply pipe reaches the set temperature.
Based on the above technical solution, optionally, in order to utilize the hot water in the water tank 31 to the maximum, the water tank 31 includes: the heat preservation tank 311, the hot water outlet pipe 312, the circulating water pipe 313 and the water inlet and outlet pipe 314, wherein a water storage cavity is formed inside the heat preservation tank 311; the hot water outlet pipe 312 is inserted into the heat preservation tank 311 and is used for outputting water in the upper area in the water storage cavity, and a pipe orifice of the hot water outlet pipe 312 positioned outside the heat preservation tank 311 forms a first water port; the circulating water pipe 313 is inserted into the heat preservation tank 311 and is used for supplying water to the upper area in the water storage cavity, and a pipe orifice of the circulating water pipe 313 positioned outside the heat preservation tank 311 forms a second water port; the water inlet and outlet pipe 314 is inserted into the heat preservation tank 311, the water inlet and outlet pipe 314 is used for supplying water to the lower area in the water storage cavity, the water inlet and outlet pipe 314 is also used for outputting water in the lower area in the water storage cavity, and a pipe orifice of the water inlet and outlet pipe 314, which is positioned outside the heat preservation tank 311, forms a third water opening. Specifically, a hot water outlet pipe 312, a circulating water pipe 313 and a water inlet and outlet pipe 314 are inserted into the heat preservation tank 311, the hot water outlet pipe 312 is used for outputting hot water in the water tank 31 to supply hot water for users, the circulating water pipe 313 is used for circulating water to flow, and the water inlet and outlet pipe 314 is used for supplying water to the water tank 31 and outputting and heating water in the water tank 31 to meet the requirement of rapidly heating water stored in the water tank 31. Thus, the water tank 31 can effectively meet the requirement of the user for using hot water, so that the hot water in the water tank 31 can be utilized to the maximum extent to heat zero-cold water or supply hot water to the outside.
Wherein, the bottom of the heat-preserving tank 311 is provided with a mounting port; the water tank 31 further comprises a sealing cover 315, the sealing cover 315 is hermetically connected to the mounting port, and the hot water outlet pipe 312, the circulating water pipe 313 and the water inlet and outlet pipe 314 are hermetically penetrated through the sealing cover 315. Specifically, the hot water outlet pipe 312, the circulating water pipe 313, and the water inlet/outlet pipe 314 are installed on the sealing cover 315, and then, the assembly is completed from the bottom of the thermal insulation tank 311 through the sealing cover 315. And the hot water outlet pipe 312, the circulating water pipe 313 and the water inlet and outlet pipe 314 are vertically arranged. In order to reduce the fluctuation range of the water temperature output by the hot water output pipe 312, the upper end of the circulating water pipe 313 is a closed structure, the pipe wall of the upper end of the circulating water pipe 313 is provided with a plurality of water outlet holes 3131, the water outlet holes 3131 are distributed on the pipe wall of the circulating water pipe 313, and the hot water output from the water outlet holes 3131 can be dispersed into the thermal insulation tank 311 to be effectively mixed with the water in the thermal insulation tank 311 so as to buffer the fluctuation of the water temperature in the thermal insulation tank 311. Meanwhile, the upper end of the hot water outlet pipe 312 is in an open structure and forms a hot water inlet 3121, the height of the hot water inlet 3121 is not lower than that of the water outlet 3131, and the hot water inlet 3121 can ensure that water in the heat-insulating tank 311 is uniformly mixed and then output. In order to increase the hot water output rate, the upper end of the water inlet/outlet pipe 314 is of a closed structure, the wall of the upper end of the water inlet/outlet pipe 314 is provided with a plurality of water through holes 3141, and when cold water is injected into the thermal insulation tank 311, the water through holes 3141 can disperse the cold water to the bottom of the thermal insulation tank 311, so that the impact on the hot water at the upper part of the thermal insulation tank 311 is reduced, and the hot water output rate is increased.
In order to detect the temperature of the water in the thermal insulation tank 311 so that the temperature of the thermal insulation tank 311 can be controlled, a first temperature sensor may be provided on the sealing lid 315 and/or a second temperature sensor may be provided on the upper portion of the thermal insulation tank 311, as required. Specifically, the first temperature sensor can detect the temperature of the incoming water at the bottom of the thermal insulation tank 311, and the second temperature sensor can detect the temperature of the outgoing water at the top of the thermal insulation tank 311.
The representation entities of the water outlet switching valve 5 and the water inlet switching valve 6 may be implemented by using an electric control valve such as a two-position three-way valve, which is not limited herein. In order to control the opening and closing of the water passage, control valves may be disposed at the heating water outlet joint 21, the heating water return joint 22, the water inlet joint 23, and the zero cold water joint 24 as needed to control the opening and closing of the water passage.
Based on the gas heating equipment, the invention further provides a heating and hot water supplying system, as shown in fig. 6, the heating and hot water supplying system includes the gas heating equipment 100, a hot water output terminal 300 and a heat dissipation terminal 200, wherein a heating water outlet joint 21 and a heating water return joint 22 of the gas heating equipment 100 are connected to the heat dissipation terminal 200, a hot water joint 25 of the gas heating equipment 100 is connected to the hot water output terminal 300, a water inlet joint 23 of the gas heating equipment 100 can be connected to a tap water pipe in a user's home, and a zero cold water joint 24 is connected to a water return pipe configured in the user's home.
In actual use, the gas heating apparatus 100 has at least the following heating modes: the heating system comprises a domestic hot water heating mode, a zero cold water heating mode and a heating water heating mode, and the following specific description is provided for different heating modes.
In the case where the gas heating apparatus 100 performs the domestic hot water heating mode.
As shown in fig. 7, in step S101, when the temperature of the water stored in the water tank is not lower than the set outlet water temperature, the gas stove is in a closed state, and the external water source enters the water tank to directly output the hot water in the water tank to the hot water output terminal. Specifically, when the temperature sensor in the water tank detects that the temperature of the hot water stored in the water tank is not lower than the set outlet temperature, the hot water stored in the water tank can meet the temperature requirement of the domestic hot water required by the user, and when the user needs to use the domestic hot water, an external water source (such as tap water) directly enters the bottom of the water tank through the water inlet joint 23, so that the hot water at the top in the water tank is output to the hot water output terminal 300 from the hot water joint 25.
And S102, starting a gas furnace under the condition that the temperature of water stored in the water tank is lower than the set water outlet temperature, heating an external water source by the gas furnace, then entering the water tank, and outputting hot water from the water tank to a hot water output terminal. Specifically, after the hot water in the water tank is used for a period of time, more cold water is injected into the water tank, so that the overall water temperature of the water tank is reduced. When the temperature of the water stored in the water tank is lower than the set water outlet temperature, the gas furnace is started and the water pump is started correspondingly, so that an external water source is heated by the gas furnace and then conveyed to the top of the water tank, and the hot water at the top in the water tank is output to the hot water output terminal 300 from the hot water joint 25.
Preferably, in the actual use process, under the condition that no domestic hot water is required to be output, if the water temperature stored in the water tank is lower than the set water outlet temperature by a difference value which is greater than a set temperature difference value delta T1, the gas furnace is started, and the water in the water tank circularly flows into the gas furnace to be heated until the water temperature stored in the water tank is higher than the set water outlet temperature by a difference value which is greater than a set temperature difference value delta T2. Specifically, under the condition that the user does not use domestic hot water, hot water in the water tank can lead to the temperature to drop because of the heat dissipation, and the water temperature is less than and sets for the leaving water temperature and the difference in temperature is greater than delta T1 in the water tank, then starts the gas furnace, and corresponding cooperation starts the water pump, and under the effect of water pump, the hydrologic cycle output in the water tank is flowed back to the water tank after being heated by the gas furnace. Thus, the water in the water tank can be circularly heated, and when the water temperature in the water tank rises and is higher than the set outlet water temperature delta T2, the gas furnace and the water pump are stopped.
In the case where the gas heating apparatus 100 performs the heating water heating mode.
In the heating water heating mode, when the return water temperature of the heating return water joint 22 is lower than the set heating temperature, the gas furnace is started to heat the return water introduced by the heating return water joint 22 under the condition that domestic hot water is not required to be heated by the gas furnace. Specifically, the heating water flows into the heat dissipation terminal 200 to heat the user's home, and when the return water temperature of the heating water is lower than the set heating temperature, the gas furnace needs to be started to heat the heating water. After the heating water in the heat dissipation terminal 200 enters the gas furnace from the heating return water joint 22 to be heated, the hot heating water is output to the heat dissipation terminal 200 through the heating water outlet joint 21.
When the domestic hot water and the heating water are both required to be heated through the gas furnace in the actual use process of a user, the domestic hot water is preferentially heated through the gas furnace. In the process of executing the heating water heating mode, the gas furnace heats the heating water so that the return water temperature of the heating return water joint 22 is lower than the set heating temperature, and the gas furnace is started to heat the heating water when the two conditions are met.
Preferably, during the actual use of the user, especially when bathing, the gas heating apparatus 100 alternately performs the domestic hot water heating mode and the heating water heating mode as needed. In order to improve the bathing experience of the user when bathing, the hot water output terminal 300 at least comprises a shower arranged in a bathroom, and the heat dissipation terminal 200 at least comprises a first radiator 201 arranged in the bathroom and a second radiator 202 arranged outside the bathroom; as shown in fig. 8, the specific control method for the heating and hot water supply system includes: after the shower is turned on in step S201, the flow rate of the heating water flowing into the first radiator 201 is increased, and the flow rate of the heating water flowing into the second radiator 202 is decreased.
Specifically, when a user bathes in the bathroom, the initial bathing stage exists, the temperature in the bathroom is low, the body feeling of the user is easy to be cold, when the bathing is finished, the temperature in the bathroom is high, the temperature difference between the bathroom and an external room is large, and the body feeling of the user after the user leaves the bathroom is still cold. By adopting the control mode, when a user bathes, the heating water flow of the first radiator 201 in the bathroom is increased in the initial stage, so that the temperature in the bathroom can be effectively increased.
In the initial bathing stage, the user can rapidly and efficiently increase the overall temperature in the bathroom through the first radiator 201, so that the poor experience that the body feeling temperature is low in the initial bathing stage of the user is reduced, and the experience of the user in the initial bathing stage is effectively improved.
As the bath time is prolonged, the temperature in the bathroom is further increased by the bath hot water, and when the cumulative shower water outlet time exceeds the first set time period t1, the heating water flow flowing into the first radiator 201 is decreased to the first rated flow, and the heating water flow flowing into the second radiator 202 is increased to the second rated flow in step S202. Specifically, after the user bathes for a period of time, the temperature in the bathroom is gradually increased, and the sensible temperature of the user is also increased, so that the first radiator 201 does not need to be provided with large-flow heating water. Thus, the first radiator 201 and the second radiator 202 can be made to normally supply the heating water. The rated flow rates of the corresponding first radiator 201 and the second radiator 202 are the corresponding flow rates of different radiators finally determined by the user according to the set temperature at home. For example: under the condition of normal heating, the set temperature of the home of the user is 25 degrees, taking the first radiator 201 as an example, the heating water flow of the first radiator 201 is adjusted until the temperature in the bathroom reaches 25 degrees, and at this time, the heating water flow of the first radiator 201 is the first rated flow; similarly, the second rated flow obtaining process of the second radiator 202 is the same as the first rated flow obtaining process, and is not described herein again.
And at the end of bathing, in order to reduce the temperature difference felt by the user when the user goes out of the bathroom, the control method further comprises the following steps: step S203, when the accumulated water outlet time of the shower exceeds a second set time t2, reducing the flow rate of the heating water circularly flowing into the first radiator 201 again, and increasing the flow rate of the heating water circularly flowing into the second radiator 202 again; wherein t1< t 2. Specifically, when the bathing time of the user reaches the time length t2, the temperature of the room outside the bathroom needs to be raised in advance. At this time, the flow rate of the heating water in the first radiator 201 is further reduced, and more heating water is supplied to the second radiator 202. And because the user is still in the bathing state, the temperature in the bathroom can be ensured not to be reduced too fast through the shower which still outputs hot water in the bathroom, and the temperature can be kept to be adjusted at a higher temperature. Meanwhile, the second radiator 202 obtains a larger flow of heating water, so that the temperature of the room outside the bathroom is rapidly raised. Therefore, after the user takes the bathroom after bathing, the temperature difference between the inside and the outside of the bathroom is small, and the discomfort of the user can be effectively reduced.
Among them, there are various ways of controlling the flow rate of heating water in the radiator, for example: the radiator is provided with a flow regulating valve for regulating flow, and the flow of the radiator is correspondingly regulated through the flow regulating valve. Taking the first radiator 201 as an example, when the flow rate of the heating water of the first radiator 201 needs to be increased, the opening degree of the flow regulating valve on the first radiator 201 is increased to increase the flow rate of the heating water; on the contrary, the opening degree of the flow rate adjustment valve on the first radiator 201 is decreased to decrease the flow rate of the heating water.
In the case where the gas heating apparatus 100 performs the zero cold water heating mode.
As shown in fig. 9, in the zero cold water heating mode, water in an external water return pipe connected to a zero cold water joint enters a water tank of the gas heating apparatus, and water introduced by the zero cold water joint is mixed with hot water stored in the water tank and is output from a hot water joint. Specifically, in the zero cold water heating mode, cold water in the external water return is drawn into the appliance by the water pump and water will flow into the tank to mix with hot water in the tank. Thus, after a period of circulating flow, the temperature of the water in the external water pipe of the device can be raised to the temperature set by the device.
Wherein, the water in the related external water return pipe can directly enter the water tank after being introduced through the zero cold water joint so as to be mixed with the hot water in the water tank. Or the water introduced from the zero cold water joint is heated by the gas furnace, enters the water tank and is mixed with the water in the water tank and then is output. The concrete description is as follows:
and S301, when the water temperature in the water tank is not less than the set outlet water temperature, circularly flowing the water in the external pipeline into the water tank, mixing the water with the water stored in the water tank, and outputting the mixed water to the external pipeline. Specifically, in the zero-cold-water mode, when the water storage temperature in the water tank is higher than the set water outlet temperature, the zero-cold-water function is realized, and the cold water in the external pipeline can be heated to the temperature set by the user through the hot water in the water tank. In this case, the water in the external pipe return enters the water tank through the zero cold water joint without being heated, and the effect of zero cold water is achieved by mixing with the hot water in the water tank. The heating of the zero cold water is realized by the hot water in the water tank, so that the gas furnace does not need to be started, the starting times of the gas furnace can be reduced, and the purpose of reducing the gas consumption is achieved.
Step S302, when the water temperature in the water tank is lower than the set water outlet temperature, the gas furnace is started, and water in the external pipeline flows into the water tank after being heated by the gas furnace, is mixed with water stored in the water tank and then is output to the external pipeline. Specifically, when the water storage temperature in the water tank is lower than the set water outlet temperature, the function of zero cold water cannot be directly achieved by heating the cold water in the external pipeline with the hot water stored in the water tank, and therefore, the function of zero cold water by starting the gas stove to heat the cold water in the introduced external pipeline is required. In this case, the water in the external pipe return pipe enters the gas furnace through the zero-cold water joint to be heated, and then the heated water flows into the water tank again to achieve the effect of zero-cold water by mixing with the hot water in the water tank. In the process of heating zero-cold water by the gas furnace, the heated water firstly enters the water tank to be mixed, and is not directly output. Like this, alright take place with avoiding out the phenomenon that the water temperature is too high and scald the user, more be favorable to improving the constant temperature degree of outlet water temperature, optimize user experience nature.
Preferably, the length of the external piping connecting the devices in the homes differs from user to user, in order to complete the zero cold water heating process within a defined time. After the device is installed in the home of a user, when the zero cold water heating mode is executed for the first time, a self-learning mode is needed to acquire the water quantity stored in the external pipeline of the device, and the specific process is as follows.
When the zero cold water heating mode is executed for the first time, detecting the initial water temperature T1 of water in the water tank and the initial water temperature T2 of water input by an external pipeline, starting the gas furnace to operate and heat at the set power P until the water temperature of the water in the water tank is detected to rise to T3, recording the heating time T of the gas furnace at the same time, and then calculating the water storage quantity L of the external pipeline. Specifically, the length of the external pipeline connecting the hot water output terminal and the equipment in each user's home is determined after the installation is completed, and correspondingly, the amount of water in the external pipeline to be heated in the zero-cold-water mode is also fixed. The water storage capacity of the water tank in the equipment is fixed, and the water storage capacity can be recorded according to the formula by measuring the water temperature T1 of the water tank, the water inlet temperature T2 of the zero cold water joint 24 and the time T for heating the water in the water tank and the external pipeline to the temperature T3 by set power: the quantity of water stored in the external pipeline can be calculated by the heat quantity Q = C × M × T = P × T (wherein C is the specific heat capacity of water, M is the mass of water, and T is the temperature rise degree). Therefore, in the zero-cold-water mode, the water flow speed can be adjusted according to the water storage capacity of the external pipeline in the house of different users, so that the heating operation of the zero-cold water is completed within a specified time.
The specific operation is as follows: and controlling the water flow speed of the external pipeline flowing into the water tank according to the calculated water storage quantity L of the external pipeline. Specifically, if the water storage quantity L of the external pipeline is greater than a set standard pipeline water quantity value L0, the water flow speed of the external pipeline flowing into the water tank is increased; and if the calculated water storage quantity L of the external pipeline is not more than the set standard pipeline water quantity value L0, reducing the water flow speed of the external pipeline flowing into the water tank. After the actual amount of stored water L is calculated in the user's home by setting a standard amount of water L0 in the apparatus before shipment from the factory, the flow rate of the zero-cooling water is adjusted by comparing the magnitudes of L and L0. That is, when L is greater than L0, the rotation speed of the water pump is increased to increase the flow rate of the zero-cold water, so that the heating speed of the zero-cold water can be increased, and the zero-cold water mode is completed within a set time.
Likewise, the set run time t0 of the zero cold water heating mode. Then, for controlling the water flow rate of the external pipeline flowing into the water tank, specifically: and calculating the water flow speed v of the external pipeline flowing into the water tank according to the water storage quantity L of the external pipeline and the set operation time t0 so as to control the water flow speed of the external pipeline flowing into the water tank. Specifically, in the zero cold water mode, the heat for heating the stored water in the external pipeline to the set temperature within the time t0 can be known according to the temperature of the water tank and the water inlet temperature of the zero cold water joint. The number of times of circulation flow is known from the quantity of heat required to heat the stored water quantity L of the external pipe and the quantity of heat exchange that can be generated by one time of circulation flow, based on the calculated quantity of heat, and the quantity of heat exchange generated by one time of circulation flow of water between the tank and the external pipe is constant, and thus the water speed is calculated from t0 and the number of times of circulation, thereby controlling the operation of the water pump.
The above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions.
Claims (10)
1. A gas heating apparatus, comprising:
the heating water outlet joint, the heating water return joint, the water inlet joint, the zero cold water joint and the hot water joint are arranged on the shell;
the gas furnace is provided with a main water outlet and a main water inlet;
the hot water supply assembly comprises a water tank and a water pump, and the water pump is connected with the water tank;
the water outlet switching valve is used for controlling the main water outlet to be selectively connected with the water tank or the heating water outlet joint;
the water inlet switching valve is used for controlling the main water inlet to be selectively connected with the water inlet connector or the heating water return connector;
the circulating pump is connected between the water inlet switching valve and the main water inlet;
wherein, hot water connects with the water tank is connected, zero cold water connects with the water pump is connected.
2. The gas heating apparatus according to claim 1, wherein the water tank has a first water port, a second water port, and a third water port; the first water port is connected with the hot water joint, the second water port is connected with the water outlet switching valve, and the third water port is respectively connected with the water inlet switching valve and the water inlet joint.
3. The gas heating apparatus according to claim 1, wherein the water pump is connected to the second water port or the third water port.
4. The gas heating apparatus according to claim 1, wherein a check valve is further provided between the zero cold water joint and the water tank.
5. The gas heating apparatus according to claim 1, wherein a plurality of hanging insertion holes are formed in a side wall of the housing, a first insertion tongue and a fixing bracket are formed in the gas furnace, the water tank is provided with a hanging bracket, a second insertion tongue is formed in the hanging bracket, the first insertion tongue and the second insertion tongue are respectively inserted into the corresponding hanging insertion holes, and the fixing bracket and the hanging bracket are fixed to the housing by screws.
6. The gas heating apparatus according to claim 2, wherein the water tank comprises:
the heat preservation tank is internally provided with a water storage cavity;
the hot water outlet pipe is inserted into the heat-preserving tank, and a pipe orifice of the hot water outlet pipe, which is positioned outside the heat-preserving tank, forms the first water gap;
the circulating water pipe is inserted into the heat-preserving tank, and a pipe orifice of the circulating water pipe positioned outside the heat-preserving tank forms the second water port;
and the water inlet and outlet pipe is inserted into the heat-insulating tank, and the pipe orifice of the water inlet and outlet pipe, which is positioned outside the heat-insulating tank, forms the third water port.
7. The gas heating apparatus according to claim 6, wherein a mounting port is provided at a bottom of the heat-insulating tank; the water tank further comprises a sealing cover, the sealing cover is connected to the mounting opening in a sealing mode, and the hot water outlet pipe, the circulating water pipe and the water inlet and outlet pipe penetrate through the sealing cover in a sealing mode.
8. The gas heating equipment according to claim 1, wherein a first expansion tank is connected to the water tank, and a second expansion tank is further connected to a pipeline between the heating water return joint and the main water inlet.
9. A heating and hot-water supplying system comprising a hot-water output terminal and a heat radiation terminal, characterized by further comprising the gas heating apparatus according to any one of claims 1 to 8; and a heating water outlet joint and a heating water return joint of the gas heating equipment are respectively connected with the heat dissipation terminal.
10. A control method for a heating and hot water supply system according to claim 9, wherein the control method comprises: executing a zero cold water heating mode;
in the zero cold water heating mode, water flowing in through the zero cold water joint enters the water tank, is mixed with water in the water tank and then is output from the hot water joint.
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