Heating furnace capable of using both zero cold water and heating hot water and control method thereof

Abstract

The present invention discloses a heating furnace and a control method capable of using zero cold water and heating hot water at the same time, including a fully premixed gas combustion system containing a burner; the flue gas generated after the burner is burned is input into a gas-water heat exchanger to perform heat exchange with the heating water in the heating water circulation system; the inlet of the gas-water heat exchanger is connected to the return water end of the heating water circulation system, and is connected to the outlet of the heat release part in the water-water exchanger through a water inlet three-way valve; the outlet of the gas-water heat exchanger outputting heating water is connected to the inlet of the heat release part in the water-water exchanger through a three-way pipe; the water-water exchanger is used to perform heat exchange between heating water and domestic water to heat domestic water; domestic water circulates in a domestic water circulation pipeline including a hot water circulation pump; a circulating heating device is provided in the domestic water circulation pipeline, and various working states can be realized through a water inlet three-way valve. The present invention has the functions of using zero cold water, heating function and domestic hot water at the same time.

Description

Technical Field

[0001] The invention relates to the technical field of heating furnace manufacturing, and in particular to a heating furnace capable of using both zero cold water and heating hot water at the same time and a control method thereof. Background Art

[0002] In the existing heating furnace manufacturing technology, the heating function will be temporarily stopped during the use of domestic hot water or the operation of the zero cold water function. When the hot water is used for too long, the indoor temperature will drop significantly due to the long heating suspension time.

[0003] Moreover, the frequent operation and stopping of the hot water function or the cold water function of the existing heating furnace will cause indoor temperature fluctuations, and the user's comfort experience is poor.

[0004] Therefore, how to make the heating furnace have higher combustion efficiency and flue gas waste heat recovery capacity, and be able to heat and use hot water at the same time has become a technical problem that technical personnel in this field urgently need to solve. Summary of the invention

[0005] In view of the above-mentioned defects of the prior art, the present invention provides a heating furnace and a control method with the functions of simultaneous use of zero cold water and heating hot water. The purpose achieved is to have the function of simultaneous use of zero cold water and heating hot water, have higher combustion efficiency and flue gas waste heat recovery capacity, and better adapt to the current environmental needs of energy conservation and emission reduction. It can use heating and hot water at the same time, and can reduce the impact of heating comfort caused by temporary closure of the heating function when hot water is used by intelligently controlling the stepping position of the three-way valve.

[0006] To achieve the above object, the present invention discloses a heating furnace capable of using both zero cooling water and heating hot water, comprising a fully premixed gas combustion system; the fully premixed gas combustion system comprises a burner, and a fan and a venturi premixing device connected to the burner in sequence;

[0007] The venturi premixing device is used to mix the gas and air;

[0008] The fan is used to extract the gas and air mixed in the Venturi premixing device and input them into the burner;

[0009] The flue gas generated after the burner is burned is input into the gas-water heat exchanger, and heat is exchanged with the heating water in the heating water circulation system through the gas-water heat exchanger;

[0010] The inlet of the air-water heat exchanger is connected to the return water end of the heating water circulation system to obtain the heating water returned after heat release, and is connected to the outlet of the heat release part of the water-water exchanger through the water inlet three-way valve, and the connection and disconnection between the outlet of the heat release part of the water-water exchanger and the inlet of the air-water heat exchanger are controlled by the water inlet three-way valve;

[0011] The outlet of the air-water heat exchanger for outputting heating water is connected to the inlet of the heat release part of the water-water exchanger through a three-way pipe;

[0012] The water-water exchanger is used to perform heat exchange between the heating water and the domestic water to heat the domestic water;

[0013] The domestic water circulates in a domestic water circulation pipeline including a hot water circulation pump;

[0014] The domestic water circulation pipeline is provided with a circulation heating device through an externally laid circulation pipeline to achieve zero cold water output.

[0015] Preferably, the flue gas generated after combustion in the burner forms low-temperature flue gas after primary heat exchange and secondary condensation heat exchange in the gas-water heat exchanger, and is finally discharged through the exhaust port at the top of the burner.

[0016] Preferably, a pipeline between the air-water heat exchanger and the water inlet three-way valve is provided with a heating circulation pump for inputting the heating water into the air-water heat exchanger.

[0017] Preferably, the domestic water includes a heating branch input into the heat absorbing part of the water-water exchanger, and a cold water branch connected in parallel with the heating branch;

[0018] The input ports of the heating branch and the cold water branch are connected to the hot water circulation pump and the regulating valve in sequence, and the output ports are connected to the bypass servo valve.

[0019] Preferably, the outlet of the heat absorbing part in the water-water exchanger is provided with a plate temperature sensor; the output port of the bypass servo valve is provided with a hot water outlet temperature sensor;

[0020] The main pipe for inputting domestic water into the heating branch and the cold water branch is provided with a water inlet temperature sensor;

[0021] The difference between the hot water outlet temperature sensor and the hot water inlet temperature sensor is used to calculate the heat load required for hot water;

[0022] The plate exchanger temperature sensor and the hot water outlet temperature sensor are both connected to a controller that controls the opening of the bypass servo valve, and the opening of the bypass servo valve is controlled according to the difference between the temperature collected by the plate exchanger temperature sensor and the temperature collected by the hot water outlet temperature sensor.

[0023] Preferably, the heating water input end and the heating water output end of the air-water heat exchanger are respectively provided with a heating water outlet temperature sensor and a heating water return temperature sensor;

[0024] The difference between the temperatures collected by the heating outlet water temperature sensor and the heating return water temperature sensor is used to compare with the heating temperature set by the user to calculate the heat load required by the full premixed gas combustion system.

[0025] The present invention also provides a control method for a heating furnace capable of using both zero cold water and heating hot water simultaneously, including using the furnace only as a heating function, using the furnace only as a domestic hot water function, or using the heating function and the domestic hot water function simultaneously;

[0026] When used only for heating function, the water inlet three-way valve switches to the external heating return water side, and the heating cycle operates according to the large circulation system, that is, the water inlet three-way valve switches to the outlet of the heat release part in the water-water exchanger and the inlet of the air-water heat exchanger are in a closed state, so that the water entering the total water inlet end of the heating water circulation system passes through the air-water heat exchanger, and is fully heat-exchanged with the high-temperature flue gas generated by the burner in the air-water heat exchanger to increase the heating water temperature. The high-temperature heating water passes through the total water outlet end of the heating water circulation system to the external heating circulation system, and is used for indoor heating through floor heating or radiators;

[0027] When used only as domestic hot water function, the heating water input end of the warm water circulation system is closed, the water inlet three-way valve is switched to a state where the outlet of the heat release part in the water-water exchanger is connected to the inlet of the air-water heat exchanger, the heating hot water enters the small circulation, the cold water of the domestic hot water enters the water-water exchanger, and fully exchanges heat with the heating small circulation hot water flowing through the water-water exchanger, and the domestic hot water is output after the temperature is increased;

[0028] When the heating function and the domestic hot water function are used at the same time, the heating water input end of the warm water circulation system is opened, and the water inlet three-way valve is switched to a position between a connected state and a closed state so that the outlet of the heat release part in the water-water exchanger and the inlet of the air-water heat exchanger are connected, and the heating external circulation and the heating small circulation are kept open at the same time, so as to achieve the functions of heating and hot water being used at the same time.

[0029] Beneficial effects of the present invention:

[0030] Compared with ordinary atmospheric combustion heating furnaces, the present invention has higher combustion efficiency and flue gas waste heat recovery capacity, is more adaptable to the current environmental needs of energy conservation and emission reduction, can be used for heating and hot water at the same time, and can reduce the impact on heating comfort caused by temporary closure of the heating function when hot water is used by intelligently controlling the stepping position of the three-way valve.

[0031] The heating furnace with the function of using both cold water and hot water for heating can effectively reduce the frequent start and stop of the heating cycle, improve the comfort of hot water use, and reduce the impact on heating comfort caused by temporary closure of the heating function when hot water is used.

[0032] The concept, specific structure and technical effects of the present invention will be further described below in conjunction with the accompanying drawings to fully understand the purpose, characteristics and effects of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 A schematic structural diagram of a fully premixed gas combustion system in one embodiment of the present invention is shown.

[0034] Figure 2 A schematic structural diagram of an embodiment of the present invention is shown.

[0035] Figure 3 A schematic diagram showing the state of an embodiment of the present invention when used for heating function.

[0036] Figure 4 A schematic diagram showing the state of an embodiment of the present invention when used as a domestic hot water function.

[0037] Figure 5 A schematic diagram showing the state of an embodiment of the present invention when used for heating and hot water. DETAILED DESCRIPTION Example

[0038] like Figure 1 and Figure 2 As shown, the heating furnace with zero cooling water and heating hot water used at the same time includes a full premixed gas combustion system; the full premixed gas combustion system includes a burner 14, and a fan 13 and a venturi premixing device 12 connected to the burner 14 in sequence;

[0039] The venturi premixing device 12 is used to mix the gas and air;

[0040] The fan 13 is used to extract the mixed gas and air in the venturi premixing device 12 and input them into the burner 14;

[0041] The flue gas generated by the burner 14 after combustion is input into the gas-water heat exchanger 24, and heat is exchanged with the heating water in the heating water circulation system through the gas-water heat exchanger 24;

[0042] The inlet of the air-water heat exchanger 24 is connected to the return water end of the heating water circulation system to obtain the heating water returned after the heat release is completed, and is connected to the outlet of the heat release part in the water-water exchanger 34 through the water inlet three-way valve 21. The connection and disconnection between the outlet of the heat release part in the water-water exchanger 34 and the inlet of the air-water heat exchanger 24 are controlled by the water inlet three-way valve 21;

[0043] The outlet of the air-water heat exchanger 24 for outputting heating water is connected to the inlet of the heat release part of the water-water exchanger 34 through a three-way pipe;

[0044] The water-water exchanger 34 is used to perform heat exchange between heating water and domestic water to heat the domestic water;

[0045] Domestic water circulates in a domestic water circulation pipeline including a hot water circulation pump 33;

[0046] The domestic water circulation pipeline is passed through an externally laid circulation pipeline, and a circulation heating device is set up to achieve zero cold water output.

[0047] The present invention can realize the function of using both heating and hot water at the same time. Compared with the traditional heating furnace three-way valve which can only switch to the hot water side or the heating side, the water inlet three-way valve 21 can adjust the water inlet three-way valve 21 to control any opening between the outlet of the heat release part in the water-water exchanger 34 and the inlet of the air-water heat exchanger 24. According to user needs, the hot water demand can be met while reducing the impact of hot water use on the heating temperature.

[0048] The gas input pipeline of the burner 14 is usually further provided with a gas valve 11 for control.

[0049] The circulating heating device of the domestic water circulation pipeline including the hot water circulation pump 33 can keep hot water of the set temperature in the pipeline from the heating furnace to the hot water water point, realizing the zero cold water function, avoiding the disadvantage that the conventional heating furnace starts heating only when the valve of the hot water water point is opened, and the water point needs to wait for the cold water stored in the pipeline to flow out before obtaining hot water. The water temperature in the hot water pipeline can be kept close to the temperature set by the user, so that hot water can be used at any time when it is turned on.

[0050] In actual applications, you can also set a single hot water circulation function according to user habits, or a standard circulation function that always maintains the water temperature, as well as a circulation reservation function that is turned on during a specific time period every day according to the user's daily living habits.

[0051] In some embodiments, the flue gas generated by the burner 14 after combustion forms low-temperature flue gas after primary heat exchange and secondary condensation heat exchange in the air-water heat exchanger 24 , and is finally discharged through the exhaust port at the top of the burner 14 .

[0052] In some embodiments, a heating circulation pump 22 is provided in the pipeline between the air-water heat exchanger 24 and the water inlet three-way valve 21 for inputting heating water into the air-water heat exchanger 24 .

[0053] In some embodiments, the domestic water includes a heating branch that inputs the heat absorbing portion of the water-water exchanger 34, and a cold water branch connected in parallel with the heating branch;

[0054] The input ports of the heating branch and the cold water branch are connected to the hot water circulation pump 33 and the regulating valve 31 in sequence, and the output ports are connected to the bypass servo valve 36 .

[0055] In actual application, domestic water in the heating branch and the cold water branch is pumped in by the hot water circulation pump 33, and the amount is adjusted by the regulating valve 31. After passing through the hot water circulation pump, it is divided into the heating branch and the cold water branch. After the domestic water in the heating branch completes heat exchange and heats up, it enters the bypass servo valve 36 together with the cold water in the cold water branch. After being mixed in the bypass servo valve 36, it is transported to the water use end through the domestic water outlet.

[0056] When the hot water circulation function is used, the mixed hot water at the hot water outlet is transported back to the hot water inlet through the external pipeline and the external one-way valve, and the hot water circulation pump 33 is used to overcome the pipeline resistance loss, keep the hot water flowing in the hot water circulation pipeline and maintain a constant hot water temperature.

[0057] In some embodiments, the outlet of the heat absorbing part of the water-water exchanger 34 is provided with a plate exchange temperature sensor 35; the output port of the bypass servo valve 36 is provided with a hot water outlet temperature sensor 37;

[0058] The main pipes of the domestic water input heating branch and the cold water branch are provided with an inlet water temperature sensor 32;

[0059] The difference between the hot water outlet temperature sensor 37 and the water inlet temperature sensor 32 is used to calculate the heat load required for hot water;

[0060] The plate exchanger temperature sensor 35 and the hot water outlet temperature sensor 37 are both connected to a controller that controls the opening of the bypass servo valve 36 , and the opening of the bypass servo valve 36 is controlled according to the difference between the temperature collected by the plate exchanger temperature sensor 35 and the temperature collected by the hot water outlet temperature sensor 37 .

[0061] When the user uses hot water, the incoming water after the hot water circulation pump is divided into two paths. One path enters the water-water exchanger 34 and fully exchanges heat with the small heating circulation hot water flowing through the water-water exchanger 34. The temperature of the domestic hot water rises and reaches the bypass servo valve 36. The other path of cold water passing through the hot water circulation pump directly reaches the bypass servo valve 36. After the two paths of domestic hot water are mixed in the bypass servo valve 36, they are transported to the water use end through the hot water outlet. According to the required outlet water temperature set by the user, the system judges the plate-to-plate temperature sensor 35 and the hot water outlet temperature sensor 37, and adjusts the heat load to reach the required temperature. When the inlet water temperature is high and the outlet water temperature is set to a low level, if the system adjusts the heat load to the minimum heat load and still cannot meet the set temperature requirement, the opening of the bypass servo valve 36 can be adjusted to adjust the mixing ratio of cold water and hot water to obtain the set temperature that meets the user's needs. In addition, when there is a demand for domestic hot water, the heating furnace combustion system can automatically start and stop the gas combustion heating system, and in both the combustion and non-combustion states, the bypass servo valve 36 can adjust the flow ratio of the two branches of hot water in real time to ensure that both the combustion and non-combustion states can achieve the set temperature that meets the user's needs. Conventional heating furnaces will cause a sharp change in water temperature when switching between combustion and non-combustion, so they can only achieve combustion with the minimum heat load, but cannot achieve comfortable temperature control below the minimum heat load to meet the heat production demand.

[0062] In some embodiments, the heating water input end and the heating water output end of the air-water heat exchanger 24 are respectively provided with a heating water outlet temperature sensor 25 and a heating water return temperature sensor 23;

[0063] The difference between the temperatures collected by the heating water outlet temperature sensor 25 and the heating water return temperature sensor 23 is used to compare with the heating temperature set by the user to calculate the heat load required by the full premix gas combustion system.

[0064] The above technical means can make the heating furnace easier to accurately control the temperature and quickly reach the working conditions required by the user.

[0065] like Figures 3 to 5 As shown, the present invention also provides a control method for a heating furnace capable of using both zero cold water and heating hot water simultaneously, including using it only as a heating function, using it only as a domestic hot water function, or using the heating function and the domestic hot water function simultaneously;

[0066] When used only as a heating function, the water inlet three-way valve 21 switches to the external heating return water side, and the heating cycle operates according to the large circulation system, that is, the water inlet three-way valve 21 switches to the outlet of the heat release part in the water-water exchanger 34 and the inlet of the air-water heat exchanger 24 are in a closed state, so that the water entering the total water inlet end of the heating water circulation system passes through the air-water heat exchanger 24, and is fully heat-exchanged with the high-temperature flue gas generated by the burner 14 in the air-water heat exchanger 24, thereby raising the heating water temperature, and the high-temperature heating water passes through the total water outlet end of the heating water circulation system to the external heating circulation system, and is used for indoor heating through floor heating or radiators;

[0067] When used only as domestic hot water, the heating water input end of the warm water circulation system is closed, and the water inlet three-way valve 21 is switched to a state where the outlet of the heat release part in the water-water exchanger 34 is connected to the inlet of the air-water heat exchanger 24, and the heating hot water enters the small circulation, and the cold water of the domestic hot water enters the water-water exchanger 34, and fully exchanges heat with the heating small circulation hot water flowing through the water-water exchanger 34, and the domestic hot water is output after the temperature rises;

[0068] When the heating function and the domestic hot water function are used at the same time, the heating water input end of the warm water circulation system is opened, and the water inlet three-way valve 21 is switched to a position between the outlet of the heat release part of the water-water exchanger 34 and the inlet of the air-water heat exchanger 24 are in a connected state and a closed state, keeping the heating external circulation and the heating small circulation open at the same time, so as to achieve the functions of heating and hot water at the same time.

[0069] The preferred specific embodiments of the present invention are described in detail above. It should be understood that a person skilled in the art can make many modifications and changes based on the concept of the present invention without creative work. Therefore, any technical solution that can be obtained by a person skilled in the art through logical analysis, reasoning or limited experiments based on the concept of the present invention on the basis of the prior art should be within the scope of protection determined by the claims.

Claims

1. A heating furnace capable of using both zero cooling water and heating hot water, including a fully premixed gas combustion system; characterized in that: The fully premixed gas combustion system comprises a burner (14), and a fan (13) and a venturi premixing device (12) connected to the burner (14) in sequence; The Venturi premixing device (12) is used to mix the fuel gas and air; The fan (13) is used to extract the fuel gas and the air mixed in the Venturi premixing device (12) and input them into the burner (14); The flue gas generated after combustion by the burner (14) is input into the gas-water heat exchanger (24), and heat exchange is performed with heating water in the heating water circulation system through the gas-water heat exchanger (24); The inlet of the air-water heat exchanger (24) is connected to the return water end of the heating water circulation system to obtain the heating water returned after heat release, and is connected to the outlet of the heat release part of the water-water exchanger (34) through the water inlet three-way valve (21). The connection and disconnection between the outlet of the heat release part of the water-water exchanger (34) and the inlet of the air-water heat exchanger (24) are controlled by the water inlet three-way valve (21); The outlet of the air-water heat exchanger (24) for outputting heating water is connected to the inlet of the heat release part of the water-water exchanger (34) via a three-way pipe; The water-water exchanger (34) is used to perform heat exchange between the heating water and the domestic water to heat the domestic water; The domestic water circulates in a domestic water circulation pipeline including a hot water circulation pump (33); The domestic water circulation pipeline is provided with a circulation heating device through an externally laid circulation pipeline to achieve zero cold water output; The domestic water circulation pipeline comprises a heating branch connected to the heat absorbing part of the water-water exchanger (34), and a cold water branch connected in parallel with the heating branch; The input ports of the heating branch and the cold water branch are connected to the hot water circulation pump (33) and the regulating valve (31) in sequence, and the output ports are connected to the bypass servo valve (36); The outlet of the heat absorbing part of the water-water exchanger (34) is provided with a plate temperature sensor (35); the output port of the bypass servo valve (36) is provided with a hot water outlet temperature sensor (37); The main pipe for inputting domestic water into the heating branch and the cold water branch is provided with a water inlet temperature sensor (32); The difference between the hot water outlet temperature sensor (37) and the water inlet temperature sensor (32) is used to calculate the heat load required for the hot water; The plate heat exchanger temperature sensor (35) and the hot water outlet temperature sensor (37) are both connected to a controller for controlling the opening of the bypass servo valve (36), and the opening of the bypass servo valve (36) is controlled according to the difference between the temperature collected by the plate heat exchanger temperature sensor (35) and the temperature collected by the hot water outlet temperature sensor (37); The heating water input end and the heating water output end of the air-water heat exchanger (24) are respectively provided with a heating water outlet temperature sensor (25) and a heating water return temperature sensor (23); The difference between the temperatures collected by the heating water outlet temperature sensor (25) and the heating water return temperature sensor (23) is used to compare with the heating temperature set by the user to calculate the heat load required by the full premixed gas combustion system.

2. The heating furnace capable of using both cold water and hot water for heating according to claim 1, characterized in that: The flue gas generated by the burner (14) after combustion forms low-temperature flue gas after primary heat exchange and secondary condensation heat exchange in the gas-water heat exchanger (24), and is finally discharged through the exhaust port at the top of the burner (14).

3. The heating furnace capable of using both cold water and hot water for heating according to claim 1, characterized in that: The pipeline between the air-water heat exchanger (24) and the water inlet three-way valve (21) is provided with a heating circulation pump (22) for inputting the heating water into the air-water heat exchanger (24).

4. The control method of a heating furnace capable of using both cold water and hot water for heating according to any one of claims 1 to 3, characterized in that: This includes using it only for heating function, only for domestic hot water function, or using it for both heating function and domestic hot water function; When used only for heating, the water inlet three-way valve (21) switches to the external heating return water side, and the heating cycle operates according to the large circulation system, that is, the water inlet three-way valve (21) switches to the outlet of the heat release part in the water-water exchanger (34) and the inlet of the air-water heat exchanger (24) are in a closed state, so that the water entering the total water inlet end of the heating water circulation system passes through the air-water heat exchanger (24), and is fully heat-exchanged with the high-temperature flue gas generated by the burner (14) in the air-water heat exchanger (24), thereby raising the heating water temperature, and the high-temperature heating water passes through the total water outlet end of the heating water circulation system to the external heating circulation system, and is used for indoor heating through floor heating or heat sinks; When used only as domestic hot water, the heating water input end of the warm water circulation system is closed, the water inlet three-way valve (21) is switched to a state where the outlet of the heat release part of the water-water exchanger (34) is connected to the inlet of the air-water heat exchanger (24), the heating hot water enters the small circulation, the cold water of the domestic hot water enters the water-water exchanger (34), fully exchanges heat with the heating small circulation hot water flowing through the water-water exchanger (34), and the domestic hot water is output after the temperature is increased; When the heating function and the domestic hot water function are used simultaneously, the heating water input end of the warm water circulation system is opened, and the water inlet three-way valve (21) is switched to a position between a connected state and a closed state between the outlet of the heat release part of the water-water exchanger (34) and the inlet of the air-water heat exchanger (24), so that the heating external circulation and the heating small circulation are kept in the open state at the same time, thereby achieving the functions of heating and hot water being used simultaneously.

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