Pressure compensation pipe and gas water heating equipment

Abstract

The utility model belongs to the technical field of gas water heating equipment, and discloses a pressure compensation pipe and gas water heating equipment. The pressure compensation pipe comprises a pipe body, an opening is formed in one end of the pipe body, the other end of the pipe body is closed, the opening is used for being communicated with the positive pressure end of a wind pressure switch of the gas water heating equipment, and an air hole communicated with a channel of the pipe body is formed in the outer wall of the pipe body. The outer wall of the pipe body is provided with a first limiting part and a second limiting part in the axis direction of the pipe body, the first limiting part and the second limiting part are used for abutting against a box body of the gas water heating equipment in a limiting mode, and the air hole is located between the first limiting part and the second limiting part. The pressure compensation pipe can compensate the pressure of the wind pressure switch, the problem that the pressure of the wind pressure switch is small can be solved without disassembly and maintenance, the operation is simple and efficient, and the user experience is improved.

Description

Technical Field

[0001] This utility model relates to the technical field of gas-fired water heating equipment, and in particular to a pressure compensation pipe and a gas-fired water heating equipment. Background Technology

[0002] Gas-fired water heating equipment, such as gas water heaters and gas-fired heating boilers, typically uses a pressure switch or pressure sensor to monitor the air pressure generated by the fan during startup. When the fan stops, operates at a low speed, or the exhaust pipe is blocked, the amount of air entering the gas-fired water heating equipment decreases, leading to incomplete combustion and an increase in CO concentration in the flue gas. The gas-fired water heating equipment should be shut down before the CO concentration in the flue gas exceeds 0.2%. The gas-fired water heating equipment uses a pressure switch to control the boiler's operation. When the air volume decreases, the pressure transmitted to the pressure switch through the fan's venturi tube decreases, potentially failing to reach the switch's closing value, and the controller then shuts down the gas-fired water heating equipment.

[0003] In existing technology, the negative and positive pressure ends of the air pressure switch in gas-fired water heaters are both located inside the boiler's casing. When the fan speed is low due to low power supply voltage or there is a slight blockage in the flue pipe, the air pressure will not reach the opening value of the air pressure switch, and the controller will shut down the gas-fired water heater. Currently, the common practice is to remove the front cover and air box cover and bring the pressure tapping point from inside the air box to the outside to increase the pressure difference of the air pressure switch to meet the fan operating conditions. The entire maintenance process is cumbersome. Utility Model Content

[0004] One of the problems to be solved by this utility model is to provide a pressure compensation tube, which can effectively solve the problem that the maintenance process is complicated in the prior art because it is necessary to remove the face shell, box cover plate and other parts to bring the pressure tapping point from the inside of the box to the outside in order to increase the pressure difference of the wind pressure switch.

[0005] The second problem to be solved by this utility model is to provide a gas-fired water heater that can effectively solve the problem in the prior art that requires removing parts such as the front shell and the cover plate of the box to bring the pressure tapping point from the inside of the box to the outside in order to increase the pressure difference of the wind pressure switch, which leads to a complicated maintenance process.

[0006] The first problem mentioned above is solved by the following technical solution:

[0007] The pipe body has an opening at one end and is closed at the other end. The opening is used to connect with the positive pressure terminal of the air pressure switch of the gas water heater. The outer wall of the pipe body is provided with an air hole that communicates with the channel of the pipe body.

[0008] The outer wall of the pipe is provided with a first limiting part and a second limiting part along the axial direction of the pipe, which are respectively used to abut against the housing of the gas water heater. The air hole is located between the first limiting part and the second limiting part.

[0009] The pressure compensation tube described in this utility model has the following advantages compared with the prior art:

[0010] The pressure compensation pipe provided by this utility model is used in gas water heaters. The gas water heater housing has mounting holes, and the pipe passes through these holes with one closed end extending out of the housing. When the gas water heater is operating normally, the second limiting part abuts against the outer wall of the housing to prevent the pipe from falling completely into the housing. At this time, the gas outlet is located inside the housing. When low power supply voltage causes low fan speed or slight blockage in the exhaust pipe, the pressure difference between the positive and negative pressure terminals of the pressure switch decreases, causing the gas water heater to stop operating. [The last sentence appears to be incomplete and requires further context.] The pulling force pulls the sealed end of the pipe towards the outside of the housing, causing the first limiting part to abut against the outer wall of the housing, so that the vent is kept outside the housing. At this time, the vent is outside the housing, and the positive pressure end of the air pressure switch is connected to the outside atmosphere through the vent. Since the external pressure is greater than the internal pressure of the housing, the pressure difference of the air pressure switch is increased, enabling the gas water heater to meet the normal working requirements. Therefore, during the adjustment of the pressure tapping point, it is not necessary to remove the front cover or housing cover to bring the pressure tapping point from the inside of the housing to the outside. This pressure compensation pipe makes the adjustment process of the pressure tapping point simple and convenient.

[0011] In one embodiment, the first limiting part is a first annular protrusion disposed on the outer wall of the tube, and the first annular protrusion can abut against the box body limiting part.

[0012] In one embodiment, the second limiting part is a second annular protrusion disposed on the outer wall of the tube, and the second annular protrusion can abut against the box body limiting part.

[0013] In one embodiment, the outer wall of the tube is further provided with a third annular protrusion and a fourth annular protrusion; the third annular protrusion and the first annular protrusion are spaced apart along the axial direction of the tube, and the third annular protrusion and the first annular protrusion form a first groove for engaging and fixing with the box body; the second annular protrusion and the fourth annular protrusion are spaced apart along the axial direction of the tube, and the second annular protrusion and the fourth annular protrusion form a second groove for engaging and fixing with the box body; the air hole is located between the fourth annular protrusion and the first annular protrusion.

[0014] In one embodiment, the outer diameter of the third annular protrusion is greater than the outer diameter of the fourth annular protrusion and the outer diameter of the first annular protrusion; the outer diameter of the second annular protrusion is greater than the outer diameter of the fourth annular protrusion and the outer diameter of the first annular protrusion.

[0015] In one embodiment, the third annular protrusion is configured as a conical structure, and the cross-section of the third annular protrusion gradually increases from the direction of the third annular protrusion to the second annular protrusion.

[0016] In one embodiment, the outer edges of both the first annular protrusion and the fourth annular protrusion are configured as arc structures.

[0017] In one embodiment, the tube is a flexible component;

[0018] A handle is provided at one closed end of the tube body; the handle includes a grip portion connected to the closed end of the tube body and an anti-slip portion provided at one end of the grip portion, wherein the outer diameter of the anti-slip portion is larger than the outer diameter of the grip portion.

[0019] The second technical problem mentioned above is solved by the following technical solution:

[0020] A gas-fired water heater includes a housing, a pressure switch, a fan, and a pressure compensation pipe as described in any of the above embodiments. The fan and the pressure switch are disposed inside the housing. The negative pressure connector of the fan is connected to the negative pressure end of the pressure switch. The opening of the pipe is connected to the positive pressure end of the pressure switch. When the first limiting part abuts against the outer wall of the housing, the air hole is located outside the housing. When the second limiting part abuts against the outer wall of the housing, the air hole is located inside the housing.

[0021] The gas-fired water heater provided by this utility model has the following advantages compared with the prior art:

[0022] The gas-fired water heater provided by this utility model achieves pressure compensation for the air pressure switch by setting a pressure compensation pipe, avoiding disassembly and maintenance, making operation simple and convenient, and improving the user experience.

[0023] In one embodiment, the top wall of the housing is provided with a mounting hole, the pipe is inserted into the mounting hole, and the wind pressure switch is disposed on the top wall of the housing. Attached Figure Description

[0024] Figure 1 This is a first structural schematic diagram of the gas-fired water heater provided in this embodiment of the utility model;

[0025] Figure 2 yes Figure 1Enlarged view of the structure at point A in the middle;

[0026] Figure 3 This is a second structural schematic diagram of the gas-fired water heater provided in this embodiment of the present invention;

[0027] Figure 4 yes Figure 3 Enlarged view of the structure at point B.

[0028] In the picture:

[0029] 1. Pressure compensation tube; 11. Tube body; 12. Air vent; 13. Second annular protrusion; 14. Fourth annular protrusion; 15. First annular protrusion; 16. Third annular protrusion; 17. Handle; 171. Grip part; 172. Anti-slip part;

[0030] 2. Fan; 21. Venturi; 3. Main heat exchanger; 4. Burner; 5. Proportional valve; 6. Controller; 7. Display; 8. Water pressure switch; 9. Air pressure switch; 91. Air pressure pipe; 10. Water pump; 20. Housing. Detailed Implementation

[0031] The embodiments of this utility model are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar parts or parts having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this utility model, and should not be construed as limiting this utility model.

[0032] In the description of this utility model, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection or a detachable connection; a mechanical connection or an electrical connection; a direct connection or an indirect connection through an intermediate medium; or the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0033] In the description of this utility model, unless otherwise expressly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0034] The technical solution of this utility model will be further described below with reference to the accompanying drawings and specific embodiments.

[0035] like Figure 1 As shown, this utility model embodiment provides a pressure compensation pipe and a gas water heater. By installing a pressure compensation pipe 1 inside the gas water heater, the problem of low fan speed caused by low power supply voltage and slight blockage in the exhaust pipe causing the controller 6 to shut down the gas water heater is solved.

[0036] The gas-fired water heater includes components such as a housing 20, a fan 2, a main heat exchanger 3, a burner 4, a proportional valve 5, a controller 6, a display 7, a water pressure switch 8, an air pressure switch 9, an air pressure pipe 91, and a water pump 10. The fan 2, the main heat exchanger 3, the burner 4, and the air pressure switch 9 are located inside the housing 20. The air pressure switch 9 is located inside the housing 20 and installed on the top wall of the housing 20. The fan 2 is equipped with a venturi 21, which is connected to the negative pressure end of the air pressure switch 9 through the air pressure pipe 91. The pressure compensation pipe 1 is connected to the positive pressure end of the air pressure switch 9.

[0037] After the gas-fired water heater is powered on via the power button on display 7, the water pressure switch 8 detects the static water pressure in the water supply pipeline. When the static water pressure reaches a certain value, the water pressure switch 8 closes. The controller 6 receives the closing signal from the water pressure switch 8 and provides power to the water pump 10. After the water pump 10 is powered on, it starts running. The water pressure switch 8 then checks again to see if the pressure reaches its closing value. If it meets the requirements, it checks if the air pressure switch 9 is open. If it is, the fan 2 is started. After the fan 2 rotates, it generates pressure through the venturi 21 installed on the fan 2. When the fan 2... Once the pressure generated by the rotation reaches the closing value of the air pressure switch 9, the air pressure switch 9 closes. Subsequently, the controller 6 provides voltage to the pulse igniter. The high voltage generated by the pulse igniter begins to discharge through the ignition needle. At the same time, the proportional valve 5 opens, and the gas enters the burner 4 through the proportional valve 5. When the gas and air mixture comes into contact with the electric spark, it ignites and burns instantly. At this time, the electro-ions generated on the flame surface flow to the controller 6 through the feedback needle. The controller 6 receives the electro-ion feedback signal and continuously supplies power to the proportional valve 5. The proportional valve 5 continues to open the gas supply, ensuring the normal operation of the gas water heater.

[0038] When the low speed of fan 2 is caused by low power supply voltage and the slight blockage of the flue pipe, causing the controller 6 to shut down the gas water heater, pressure compensation can be performed through pressure compensation pipe 1 to make the pressure of the air pressure switch 9 reach the closing value.

[0039] This gas-fired water heater uses a pressure compensation pipe 1 to compensate for the pressure of the air pressure switch 9, avoiding disassembly and maintenance, making operation simple and convenient, and improving the user experience.

[0040] Specifically, such as Figures 1-4 As shown, the pressure compensation pipe 1 includes a pipe body 11, with an opening at one end and a closed end at the other. The opening is used to connect with the positive pressure terminal of the air pressure switch 9 of the gas water heater. The outer wall of the pipe body 11 has an air hole 12 communicating with the channel of the pipe body 11. Along the axial direction of the pipe body 11, the outer wall of the pipe body 11 has a first limiting part and a second limiting part, respectively, for limiting and abutting against the housing 20 of the gas water heater. The air hole 12 is located between the first limiting part and the second limiting part. In a gas water heater using this pressure compensation pipe, the housing of the gas water heater has a mounting hole, through which the pipe body 11 passes, with the closed end of the pipe body 11 extending outside the housing 20. When the gas... When the gas water heater is running normally, the second limiting part abuts against the outer wall of the housing 20. At this time, the air hole 12 is located inside the housing 20. When the fan speed is low due to low power supply voltage and there is a slight blockage in the flue pipe, the pressure difference between the positive pressure end and the air pressure end of the air pressure switch 9 decreases, causing the gas water heater to stop running. Applying a pulling force pulls the closed end of the pipe 11 out of the housing 20, so that the first limiting part abuts against the outer wall of the housing 20. At this time, the air hole 12 is located outside the housing 20. The positive pressure end of the air pressure switch 9 is connected to the outside atmosphere through the air hole 12. Since the pressure outside is greater than the pressure inside the housing 20, the pressure difference of the air pressure switch 9 increases.

[0041] It is understandable that when the vent 12 is located inside the housing 20, the positive pressure end of the pressure switch 9 is connected to the inside of the housing 20. Since the inside of the housing 20 is under negative pressure, the positive pressure end of the pressure switch 9 is also under negative pressure. The positive and negative pressure ends of the pressure switch 9 cancel each other out. For a normally functioning gas water heater, the above structure does not pose a problem. However, when the fan 2 rotates at a low speed due to low power supply voltage or when there is a slight blockage in the exhaust pipe, the pressure of the pressure switch 9 decreases. By switching the position of the pipe 11, the vent 12 is located outside the housing 20 and connected to the outside. The pressure outside is greater than the pressure inside the housing 20, that is, the positive pressure end of the pressure switch 9 is converted to positive pressure at this time. There is a pressure difference between the positive and negative pressure ends of the pressure switch 9. Due to the existence of the pressure difference, the pressure of the pressure switch 9 reaches the closing value.

[0042] When the pressure of the wind pressure switch 9 decreases, the pressure compensation tube 1 applies a pulling force to pull the closed end of the tube body 11 outwards towards the housing 20, so that the first limiting part abuts against the outer wall of the housing 20. At this time, the air hole 12 is located outside the housing 20, and the positive pressure end of the wind pressure switch 9 is connected to the outside atmosphere through the air hole 12. Since the external pressure is greater than the internal pressure of the housing 20, the pressure difference of the wind pressure switch 9 is increased, which can compensate for the pressure of the wind pressure switch 9. The problem of small pressure difference of the wind pressure switch 9 can be solved without disassembly and maintenance. The operation is simple and efficient, and the user experience is improved.

[0043] Optionally, such as Figure 2 and Figure 4 As shown, the first limiting part is a first annular protrusion 15 provided on the outer wall of the tube body 11, and the first annular protrusion 15 can be limited and abutted against the box body 20; the second limiting part is a second annular protrusion 13 provided on the outer wall of the tube body 11, and the second annular protrusion 13 can be limited and abutted against the box body 20.

[0044] Specifically, the top wall of the housing 20 is provided with mounting holes; the outer wall of the tube 11 is also provided with a third annular protrusion 16 and a fourth annular protrusion 14; the third annular protrusion 16 and the first annular protrusion 15 are distributed at intervals along the axial direction of the tube 11, and the third annular protrusion 16 and the first annular protrusion 15 form a first slot for snapping and fixing with the housing 20; the second annular protrusion 13 and the fourth annular protrusion 14 are distributed at intervals along the axial direction of the tube 11, and the second annular protrusion 13 and the fourth annular protrusion 14 form a second slot for snapping and fixing with the housing 20; the air hole 12 is located between the fourth annular protrusion 14 and the first annular protrusion 15. By providing a second and a first slot distributed along its axis on the outer wall of the tube body 11, when the air hole 12 is located inside the housing 20, the tube body 11 is engaged with the mounting hole in the second slot and installed on the housing 20. When the air hole 12 is located outside the housing 20, the tube body 11 is engaged with the mounting hole in the first slot and installed on the housing 20. In this way, the slot structure can be engaged and fixed with the housing 20, preventing the tube body 11 from moving and causing changes in the tube hole 12, thus affecting the pressure tapping effect. Furthermore, this structure can improve the structural strength of the tube body 11 by protruding a second annular protrusion 13, a fourth annular protrusion 14, a first annular protrusion 15, and a third annular protrusion 16 on the outer wall of the tube body 11. It is understood that the second annular protrusion 13, the fourth annular protrusion 14, the first annular protrusion 15, and the third annular protrusion 16 are all made of flexible material.

[0045] Of course, in other embodiments, the second slot and the first slot can also be formed by cutting grooves in the outer wall of the tube body 11.

[0046] To prevent excessive movement of the tube body 11 when switching between the first and second mounting positions, the outer diameter of the second annular protrusion 13 is larger than the outer diameters of the fourth annular protrusion 14 and the first annular protrusion 15. The outer diameters of the fourth annular protrusion 14 and the first annular protrusion 15 are the same. The outer diameter of the third annular protrusion 16 is larger than the outer diameters of the fourth annular protrusion 14 and the first annular protrusion 15. By setting the outer diameters of the second annular protrusion 13 and the third annular protrusion 16 to be relatively large, the tube body 11 is always confined between the second annular protrusion 13 and the third annular protrusion 16 when it is moved.

[0047] To facilitate the insertion of the tube 11 into the mounting hole of the housing 20, the third annular protrusion 16 is designed as a tapered structure. From the direction of the third annular protrusion 16 to the second annular protrusion 13, the cross-section of the third annular protrusion 16 gradually increases. This structure allows the tube 11 to be inserted into the mounting hole through the end with the opening and to be engaged by the third annular protrusion 16. The tapered structure makes it easier for the third annular protrusion 16 to pass through the mounting hole.

[0048] To ensure smooth movement of the tube body 11 within the mounting hole, the outer edges of the fourth annular protrusion 14 and the first annular protrusion 15 are designed with rounded edges. By designing the outer edges of the fourth annular protrusion 14 and the first annular protrusion 15 with rounded edges, the tube body 11 can more smoothly engage with the second and first slots during movement.

[0049] In this embodiment, the tube body 11 is a flexible component, which is manufactured using a flexible material (such as rubber or silicone). Preferably, the tube body 11, the second annular protrusion 13, the fourth annular protrusion 14, the first annular protrusion 15, and the third annular protrusion 16 are an integral structure.

[0050] To facilitate the movement of the tube body 11, a handle 17 is provided at the closed end of the tube body 11. The handle 17 is located outside the housing 20. By pulling or pushing the handle 17, the tube body 11 can be switched between the first installation position and the second installation position, making the operation more convenient.

[0051] Specifically, the handle 17 includes a gripping portion 171 connected to one end of the tube body 11 that is closed, and an anti-slip portion 172 disposed at one end of the gripping portion 171. The outer diameter of the anti-slip portion 172 is larger than the outer diameter of the gripping portion 171. This structure allows the anti-slip portion 172 to provide a limit when the handle 17 is pulled by gripping the gripping portion 171, so as to prevent it from slipping out of the hand.

[0052] In other embodiments, a pull rope can also be provided at the closed end of the tube 11, so that the tube 11 can be pulled out by pulling the rope.

[0053] In another embodiment, such as Figure 1-4 As shown, the gas water heater using the aforementioned pressure compensation pipe includes a housing 20, a pressure switch 9, and a fan 2. The fan 2 and the pressure switch 9 are located inside the housing 20. The negative pressure connector of the fan 2 is connected to the negative pressure end of the pressure switch 9, and the opening of the pipe 11 is connected to the positive pressure end of the pressure switch 9. When the first limiting part abuts against the outer wall of the housing 20, the air hole 12 is located outside the housing 20. When the second limiting part abuts against the outer wall of the housing 20, the air hole is located inside the housing 20.

[0054] Furthermore, the top wall of the housing 20 is provided with a mounting hole, the pipe 11 passes through the mounting hole, and the wind pressure switch 9 is provided on the top wall of the housing 20.

[0055] In gas water heaters using this pressure compensation pipe, the housing of the gas water heater is provided with an installation hole. The pipe 11 passes through the installation hole, with one closed end of the pipe 11 extending outside the housing 20. When the gas water heater is running normally, the second limiting part abuts against the outer wall of the housing 20. At this time, the vent 12 is located inside the housing 20. When the fan speed is low due to low power supply voltage or slight blockage of the exhaust pipe, the pressure difference between the positive pressure end and the air pressure end of the pressure switch 9 decreases, causing the gas water heater to stop running. A pulling force is applied to pull the closed end of the pipe 11 out of the housing 20, so that the first limiting part abuts against the outer wall of the housing 20. At this time, the vent 12 is located outside the housing 20, and the positive pressure end of the pressure switch 9 is connected to the outside atmosphere through the vent 12. Since the external pressure is greater than the pressure inside the housing 20, the pressure difference of the pressure switch 9 is increased, which can compensate for the pressure of the pressure switch 9. The problem of low pressure difference of the pressure switch 9 can be solved without disassembly and maintenance. The operation is simple and efficient, improving the user experience.

[0056] Obviously, the above embodiments of this utility model are merely examples for clearly illustrating the present utility model, and are not intended to limit the implementation of the present utility model. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of the claims of this utility model.

Claims

1. Pressure-compensating tube for a gas-fired water heating appliance, characterized in that, The utility model relates to a kind of gas hot water equipment, including: Pipe body (11), one end of the pipe body (11) is provided with opening, the other end is closed, the opening is used to communicate with the positive pressure end of the gas pressure switch (9) of the gas hot water equipment, the outer wall of the pipe body (11) is provided with air hole (12) with the passage of the pipe body (11) communication; The outer wall of the pipe body (11) is provided with first limiting portion and second limiting portion for limiting abutment with the box (20) of the gas hot water equipment along the axis direction of the pipe body (11), and the air hole (12) is located between the first limiting portion and the second limiting portion.

2. The pressure-compensating tube according to claim 1, characterized in that The first limiting portion is first annular protrusion (15) arranged on the outer wall of the pipe body (11), and the first annular protrusion (15) can limit abutment with the box (20).

3. The pressure-compensating tube of claim 2, wherein, The second limiting portion is second annular protrusion (13) arranged on the outer wall of the pipe body (11), and the second annular protrusion (13) can limit abutment with the box (20).

4. The pressure-compensating tube according to claim 3, characterized in that The outer wall of the pipe body (11) is further provided with third annular protrusion (16) and fourth annular protrusion (14); The third annular protrusion (16) and the first annular protrusion (15) are spaced apart along the axis direction of the pipe body (11), and the first annular protrusion (15) and the third annular protrusion (16) form a first clamping groove for clamping fixation with the box (20); The second annular protrusion (13) and the fourth annular protrusion (14) are spaced apart along the axis direction of the pipe body (11), and the second annular protrusion (13) and the fourth annular protrusion (14) form a second clamping groove for clamping fixation with the box (20); The air hole (12) is located between the fourth annular protrusion (14) and the first annular protrusion (15).

5. The pressure-compensating tube of claim 4, wherein, The outer diameter of the third annular protrusion (16) is greater than the outer diameter of the fourth annular protrusion (14) and the outer diameter of the first annular protrusion (15), and the outer diameter of the second annular protrusion (13) is greater than the outer diameter of the fourth annular protrusion (14) and the outer diameter of the first annular protrusion (15).

6. The pressure-compensating tube of claim 4, wherein, The third annular protrusion (16) is arranged in a tapered structure, and the cross section of the third annular protrusion (16) gradually increases in the direction from the third annular protrusion (16) to the second annular protrusion (13).

7. The pressure-compensating tube of claim 4, wherein, The outer edge of the first annular protrusion (15) and the outer edge of the fourth annular protrusion (14) are both arranged in a circular arc structure.

8. The pressure-compensating tube according to any one of claims 1 to 7, characterized in that The pipe body (11) is a flexible member. The closed end of the pipe body (11) is provided with a handle (17), and the handle (17) includes a gripping portion (171) connected to one end of the pipe body (11) and an anti-slip portion (172) arranged at one end of the gripping portion (171), and the outer diameter of the anti-slip portion (172) is greater than the outer diameter of the gripping portion (171).

9. Gas water heating apparatus comprising a casing (20), a draft pressure switch (9), a fan (2), characterized in that, The gas water heating device further comprises the pressure compensation pipe (1) according to any one of claims 1-8, the fan (2) and the air pressure switch (9) are arranged in the box (20), a negative pressure joint of the fan (2) is communicated with a negative pressure end of the air pressure switch (9), an opening of the pipe body (11) is communicated with a positive pressure end of the air pressure switch (9), when the first limiting portion abuts against an outer wall of the box (20), the air hole (12) is located outside the box (20), when the second limiting portion abuts against the outer wall of the box (20), the air hole (12) is located inside the box (20).

10. Gas water heating apparatus according to claim 9, characterised in that, A top wall of the box (20) is provided with a mounting hole, the pipe body (11) is arranged in the mounting hole, and the air pressure switch (9) is arranged on the top wall of the box (20).

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