CN117646949A - Anti-freezing protection device and protection method for water-cooled air conditioning unit - Google Patents
Anti-freezing protection device and protection method for water-cooled air conditioning unit Download PDFInfo
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- CN117646949A CN117646949A CN202311734618.6A CN202311734618A CN117646949A CN 117646949 A CN117646949 A CN 117646949A CN 202311734618 A CN202311734618 A CN 202311734618A CN 117646949 A CN117646949 A CN 117646949A
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- 238000004378 air conditioning Methods 0.000 title claims abstract description 49
- 238000007710 freezing Methods 0.000 title claims abstract description 31
- 238000000034 method Methods 0.000 title claims abstract description 14
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 322
- 238000010438 heat treatment Methods 0.000 claims abstract description 55
- 238000005086 pumping Methods 0.000 claims abstract description 51
- 238000001514 detection method Methods 0.000 claims description 6
- 230000002528 anti-freeze Effects 0.000 claims description 3
- 230000008014 freezing Effects 0.000 abstract description 9
- 238000005336 cracking Methods 0.000 description 3
- 230000002265 prevention Effects 0.000 description 3
- 108010053481 Antifreeze Proteins Proteins 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000008236 heating water Substances 0.000 description 1
- 239000003507 refrigerant Substances 0.000 description 1
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Abstract
The invention discloses an anti-freezing protection device and a protection method for a water-cooled air conditioning unit, wherein the air conditioning unit comprises an evaporator, a water inlet pipeline and a water outlet pipeline, the water inlet pipeline and the water outlet pipeline are respectively connected with an inlet end and an outlet end of the evaporator, and the water inlet pipeline and the water outlet pipeline are communicated through the evaporator; the anti-freezing protection device comprises an auxiliary pipeline, a water pumping device and a heating device, one end of the auxiliary pipeline is communicated with the water inlet pipeline, the other end of the auxiliary pipeline is communicated with the water outlet pipeline, the water pumping device and the heating device are arranged on the auxiliary pipeline, the water pumping device is used for driving water in the water inlet pipeline and the water outlet pipeline to circularly flow through the evaporator and the auxiliary pipeline, and the heating device is used for heating the water in the auxiliary pipeline. Based on the protection device, the risk of freezing damage of the water-cooled air conditioning unit in a low-temperature environment is effectively reduced.
Description
Technical Field
The invention relates to the technical field of air conditioning unit freezing prevention, in particular to a freezing prevention protection device and a freezing prevention protection method for a water-cooled air conditioning unit.
Background
The working principle of the current water-cooled air conditioning system is mainly that water is circularly conveyed into an evaporator through a water conveying pipeline by a water pump, heat exchange is carried out with refrigerant in the evaporator to obtain low-temperature water, and then low-temperature water is output from the evaporator to terminal equipment, such as an indoor unit, so that cold and heat exchange is carried out with indoor air, heat in the air is absorbed, and the indoor temperature is reduced. However, in the actual situation, the air conditioning unit has the condition that the water temperature in the water pipeline is too low in the operation process, the water pump and the air conditioning unit are not in joint control, if the water pump fails or the water in the water pipeline does not flow, the risk of frost cracking of the evaporator is easily caused, and on the other hand, in the low-temperature environment in winter, the water reserved by the unit is also easy to cause the freezing of the evaporator when the air conditioning unit is in a stop state.
In the prior art, a mechanical water flow sensor is added on a water conveying pipeline, when the air conditioning unit operates, the water flow sensor is used for detecting the water flow state in the pipeline, if the water flow sensor detects that the water flow is smaller than a preset value, alarm information is sent, and a compressor of the air conditioning unit is forcibly stopped, so that the operation of the air conditioning unit is stopped; another conventional anti-freezing protection scheme is to install a water temperature sensor on a water pipeline, detect the temperature of a water inlet pipeline and a water outlet pipeline of the water pipeline when an air conditioning unit is stopped, and forcedly start a water pump to avoid freezing damage of an evaporator if the water temperature is too low and has a freezing risk.
However, the water pump in the scheme is not combined with the air conditioner unit, and the failure of the anti-freezing protection can be caused under the condition that the water flow sensor possibly fails. More importantly, if the external temperature is low, even if the water pump is forcibly started in the shutdown state of the air conditioning unit, the risk of frost cracking of the evaporator cannot be avoided.
Disclosure of Invention
The invention aims to provide an anti-freezing protection device and an anti-freezing protection method for a water-cooled air conditioning unit, which can still effectively avoid the air conditioning unit from being frozen down under the conditions that water in a water inlet pipeline and a water outlet pipeline in the air conditioning unit do not flow and are in an extremely low-temperature environment.
In order to achieve the above purpose, the invention discloses an anti-freezing protection device of a water-cooled air conditioning unit, which comprises an evaporator, a water inlet pipeline and a water outlet pipeline, wherein the water inlet pipeline and the water outlet pipeline are respectively connected with the inlet end and the outlet end of the evaporator, and the water inlet pipeline and the water outlet pipeline are communicated through the evaporator; the anti-freezing protection device comprises an auxiliary pipeline, a water pumping device and a heating device, wherein one end of the auxiliary pipeline is communicated with the water inlet pipeline, the other end of the auxiliary pipeline is communicated with the water outlet pipeline, the water pumping device and the heating device are arranged on the auxiliary pipeline, the water pumping device is used for driving water in the water inlet pipeline, the water in the water outlet pipeline circularly flows through the evaporator and the auxiliary pipeline, and the heating device is used for heating the water in the auxiliary pipeline.
Preferably, a first water flow sensor is arranged on the water outlet pipeline, and a controller is electrically connected with the first water flow sensor, the pumping device and the heating device, and can control the states of the pumping device and the heating device according to the detection result of the first water flow sensor.
Preferably, the auxiliary pipeline is provided with a second water flow sensor, and a controller is electrically connected with the second water flow sensor, the pumping device and the heating device, and the controller can control the states of the pumping device and the heating device according to the detection result of the second water flow sensor.
Preferably, the water outlet pipeline and the water inlet pipeline are provided with pressure sensors for measuring water pressure, and are electrically connected with the pressure sensors, the water pumping device and the heating device, and the controller can control the states of the water pumping device and the heating device according to the pressure difference between the water outlet pipeline and the water inlet pipeline detected by the pressure sensors.
Preferably, the auxiliary pipeline is provided with a check valve, and the check valve is used for limiting water in the water inlet pipeline from flowing back into the auxiliary pipeline.
The invention also discloses an anti-freezing protection method of the water-cooled air conditioning unit, the air conditioning unit comprises an evaporator, a water inlet pipeline and a water outlet pipeline, the water inlet pipeline and the water outlet pipeline are respectively connected with the inlet end and the outlet end of the evaporator, and the water inlet pipeline and the water outlet pipeline are communicated through the evaporator; the anti-freezing protection method comprises the following steps: providing an auxiliary pipeline, a water pumping device and a heating device, wherein one end of the auxiliary pipeline is communicated with the water inlet pipeline, the other end of the auxiliary pipeline is communicated with the water outlet pipeline, and the water pumping device and the heating device are arranged on the auxiliary pipeline; and controlling the opening or closing of the water pumping device and the heating device according to the state parameters of the water in the water outlet pipeline and/or the water inlet pipeline, wherein when the water pumping device and the heating device are in an opening state, the water in the water inlet pipeline and the water outlet pipeline circularly flows from the auxiliary pipeline to the evaporator and is heated in the auxiliary pipeline.
Preferably, the state parameter of the water includes a water pressure difference between the water inlet pipeline and the water outlet pipeline, when the air conditioning unit is operated, if the water pressure difference is smaller than a set value, the operation of the air conditioning unit is forcibly stopped, and the water pumping device and the heating device are started.
Preferably, the state parameters of the water further include a first water flow rate in the water inlet pipeline and/or the water outlet pipeline, when the air conditioning unit operates, if the first water flow rate is smaller than a set value, the operation of the air conditioning unit is forcedly stopped, and at the moment, if the water pumping device and the heating device are in a working state, the water pumping device and the heating device are controlled to continuously operate for a preset period of time.
Preferably, the state parameters of the water comprise water temperature in the water inlet pipeline and/or the water outlet pipeline, when the air conditioning unit is stopped, the water temperature in the water inlet pipeline and/or the water outlet pipeline is detected, and when the water temperature is smaller than or equal to a set value, the water pumping device and the heating device are started; and when the water temperature is greater than a set value, closing the water pumping device and the heating device.
Preferably, the state parameter of the water further includes a second water flow rate in the auxiliary pipeline, when the water temperature reaches a condition of starting the pumping device and the heating device, the pumping device and the heating device are started and a buffer time is continued, and at this time, if the second water flow rate is smaller than a set value, the pumping device and the heating device are closed.
Compared with the prior art, the technical scheme disclosed by the invention has the advantages that the water outlet pipeline and the water inlet pipeline of the air conditioning unit are provided with the auxiliary pipeline communicated with the water outlet pipeline, the auxiliary pipeline is provided with the water pumping device and the heating device, the water pumping device drives the water inlet pipeline and the water outlet pipeline to circularly flow to the evaporator through the auxiliary pipeline, and the heating device heats the water flowing through the evaporator in the auxiliary pipeline, so that the water pumping device and the heating device can be used for heating the water circulating through the evaporator, the risk of frost cracking of the evaporator of the air conditioning unit under various conditions can be effectively reduced on the premise of not influencing the normal operation of the air conditioning unit, and the stability and the reliability of the water-cooled air conditioning unit under winter or low-temperature environments are remarkably improved.
Drawings
Fig. 1 is a schematic structural diagram of an antifreezing protection device for a water-cooled air conditioning unit in an embodiment of the invention.
Detailed Description
In order to describe the technical content, the constructional features, the achieved objects and effects of the present invention in detail, the following description is made in connection with the embodiments and the accompanying drawings.
The embodiment discloses an anti-freezing protection device of a water-cooled air conditioner unit, which is used for anti-freezing protection of the air conditioner unit. As shown in fig. 1, the air conditioning unit in this embodiment includes an evaporator 8, a water inlet pipeline 1 and a water outlet pipeline 2, the water inlet pipeline 1 and the water outlet pipeline 2 are respectively connected to an inlet end and an outlet end of the evaporator 8, the water inlet pipeline 1 and the water outlet pipeline 2 are communicated through the evaporator 8, and a first water pump 3 is installed on the water inlet pipeline 1. In a normal state, the first water pump 3 delivers water from the water inlet pipeline 1 into the evaporator 8 and then flows out from the water outlet pipeline 2 at the other end of the evaporator 8, and the water flows through a path a, b, c, d.
However, in a low temperature environment, if the water in the water inlet line 1 and/or the water outlet line 2 does not flow or the flow rate is small, while the evaporator 8 is in operation and still continues to exchange heat with the water entering the evaporator 8 from the water inlet line 1, the water temperature in the evaporator 8 is too low, with the risk of being frozen. To avoid this risk, the present embodiment discloses an anti-freeze protection device. The anti-freezing protection device comprises an auxiliary pipeline 11, a water pumping device 13 and a heating device 15, wherein the water pumping device 13 and the heating device 15 are arranged on the auxiliary pipeline 11, and specifically, the water pumping device comprises a second water pump 13, and the heating device comprises an electric heater 15. One end of the auxiliary pipeline 11 is communicated with the water inlet pipeline 1, and the other end is communicated with the water outlet pipeline 2. The second water pump 13 and the electric heater 15 are arranged on the auxiliary pipeline 11, the second water pump 13 is used for driving water in the water inlet pipeline 1 and the water outlet pipeline 2 to circularly flow to the evaporator 8 through the auxiliary pipeline 11, the electric heater 15 is used for heating water in the auxiliary pipeline 11, and the second water pump 13 and the electric heater 15 are electrically connected with a controller (not shown). The controller controls the second water pump 13 and the electric heater 15 to be turned on or off according to the state parameters of the water in the water outlet pipeline 2 and/or the water inlet pipeline 1, and when the second water pump 13 and the electric heater 15 are in an on state, the water in the water inlet pipeline 1 and the water outlet pipeline 2 circularly flows from the auxiliary pipeline 11 to the evaporator 8 and is heated in the auxiliary pipeline 11.
Further, the state parameters of the water include the water pressure difference between the water inlet pipeline 1 and the water outlet pipeline 2 when the air conditioning unit is operated. The water inlet pipeline 1 and the water outlet pipeline 2 are respectively provided with a first pressure sensor 5 and a second pressure sensor 6 for detecting water pressure, and the first pressure sensor 5 and the second pressure sensor 6 are electrically connected with a controller. The controller calculates the water pressure difference according to the water pressure detected by the first pressure sensor 5 and the second pressure sensor 6, if the water pressure difference is smaller than a set value, the operation of the compressor 9 of the air conditioning unit is forcibly stopped, and the second water pump 13 and the electric heater 15 on the auxiliary pipeline 11 are started by the controller, so that the heated water can circularly flow into the evaporator 8 in the auxiliary pipeline 11.
Further, a check valve 14 is provided on the auxiliary line 11, the check valve 14 being used to restrict the backflow of water in the water inlet line 1 into the auxiliary line 11, the water flowing through the line e, f, g, b, c, e during circulation.
Further, the state parameter of the water comprises the first water flow in the water inlet line 1 and/or the water outlet line 2, in addition to by detecting the water pressure difference between the water inlet line 1 and the water outlet line 2. As shown in fig. 1, the water outlet pipeline 1 is provided with a first water flow sensor 4, the first water flow sensor 4 is electrically connected with a controller, when the air conditioner unit is operated, if the first water flow sensor 4 detects that the first water flow is smaller than a set value, the operation of the compressor 9 of the air conditioner unit is forcibly stopped, and at this time, if the second water pump 13 and the electric heater 15 are in an operating state, the controller controls the second water pump 13 and the electric heater 15 to continuously heat for a period of time, for example, 300s.
On the other hand, when the air conditioning unit is in a shutdown state, in order to avoid freezing of water in the water inlet pipeline 1 and/or the water outlet pipeline 2 in a low-temperature environment, further freezing the evaporator 8, the detection of the state parameters of the water further comprises detecting the water temperature in the water inlet pipeline 1 and/or the water outlet pipeline 2, as shown in fig. 1, detecting the water temperature in any one of the positions B1 and B2 on the water inlet pipeline and the water outlet pipeline, and the controller controls the second water pump 13 and the electric heater 15 to be turned on or turned off according to the magnitude relation between the water temperature and the set value. If the water temperature is less than or equal to the set value, the second water pump 13 and the electric heater 15 are turned on; if the water temperature is greater than the temperature set point, the second water pump 13 and the electric heater 15 are turned off.
Further, when the air conditioning unit is in a shutdown state and meets the condition of opening the electric heater 15, in order to avoid dry burning of the electric heater 15, it is necessary to ensure that water flows through the auxiliary pipeline 11, so the auxiliary pipeline 11 is provided with a second water flow sensor 12, and the second water flow sensor 12 is electrically connected with the controller. When the water temperature meets the condition of turning on the second water pump 13 and the electric heater 15, the second water pump 13 and the electric heater 15 are turned on by the controller and continuously operated for a period of time, such as 5s. After 5s, if the second water flow sensor 12 detects that the second water flow in the auxiliary pipeline 11 is smaller than the set value, the controller turns off the second water pump 13 and the electric heater 15; if the second water flow in the auxiliary pipeline 11 is normal, the states of the second water pump 13 and the electric heater 15 are unchanged, and the second water pump 13 and the electric heater 15 are turned off until the water temperature is greater than a set value, so that the condition of dry burning of the electric heater 15 in the auxiliary pipeline 11 is avoided.
In summary, the above embodiment of the invention discloses an anti-freezing protection device for a water-cooled air conditioning unit, which can sensitively sense the water flow state in a water inlet and outlet pipeline under the double detection of a first pressure sensor 5, a second pressure sensor 6 and a first water flow sensor 4, and once the detected water flow is smaller than a set value or the water pressure difference is smaller than the set value, a second water pump 13 and an electric heater 15 on an auxiliary pipeline 11 are started, so that the safety of the air conditioning unit during operation is effectively ensured; in the other case, in the state that the air conditioning unit is stopped, the water temperature in the water inlet pipeline 1 and/or the water outlet pipeline 2 is detected, the second water pump 13 and the electric heater 15 are controlled to be turned on or off according to the magnitude relation between the water temperature and the temperature set value, and the condition of dry burning of the electric heater 15 in the auxiliary pipeline 11 is prevented by the second water flow sensor 12. The protection device can effectively protect the air conditioning unit from being frozen out under different states of the air conditioning unit.
The foregoing description of the preferred embodiments of the present invention is not intended to limit the scope of the claims, which follow, as defined in the claims.
Claims (10)
1. The anti-freezing protection device of the water-cooled air conditioning unit is characterized by comprising an evaporator, a water inlet pipeline and a water outlet pipeline, wherein the water inlet pipeline and the water outlet pipeline are respectively connected with the inlet end and the outlet end of the evaporator, and the water inlet pipeline and the water outlet pipeline are communicated through the evaporator;
the anti-freezing protection device comprises an auxiliary pipeline, a water pumping device and a heating device, wherein one end of the auxiliary pipeline is communicated with the water inlet pipeline, the other end of the auxiliary pipeline is communicated with the water outlet pipeline, the water pumping device and the heating device are arranged on the auxiliary pipeline, the water pumping device is used for driving water in the water inlet pipeline, the water in the water outlet pipeline circularly flows through the evaporator and the auxiliary pipeline, and the heating device is used for heating the water in the auxiliary pipeline.
2. The water-cooled air conditioning unit anti-freezing protection device according to claim 1, wherein a first water flow sensor is arranged on the water outlet pipeline, and a controller is further electrically connected with the first water flow sensor, the water pumping device and the heating device, and can control states of the water pumping device and the heating device according to detection results of the first water flow sensor.
3. The water-cooled air conditioning unit anti-freezing protection device according to claim 1, wherein the auxiliary pipeline is provided with a second water flow sensor, and a controller is electrically connected with the second water flow sensor, the water pumping device and the heating device, and can control the states of the water pumping device and the heating device according to the detection result of the second water flow sensor.
4. The antifreeze protection device of the water-cooled air conditioner set according to claim 1, wherein the water outlet pipeline and the water inlet pipeline are provided with pressure sensors for measuring water pressure, and a controller is electrically connected with the pressure sensors, the water pumping device and the heating device, and can control the states of the water pumping device and the heating device according to the pressure difference between the water outlet pipeline and the water inlet pipeline detected by the pressure sensors.
5. The antifreeze protection device of the water-cooled air conditioner set according to claim 1, wherein the auxiliary pipeline is provided with a check valve for restricting the water in the water inlet pipeline from flowing back into the auxiliary pipeline.
6. The anti-freezing protection method for the water-cooled air conditioning unit is characterized in that the air conditioning unit comprises an evaporator, a water inlet pipeline and a water outlet pipeline, wherein the water inlet pipeline and the water outlet pipeline are respectively connected with the inlet end and the outlet end of the evaporator, and the water inlet pipeline and the water outlet pipeline are communicated through the evaporator;
the anti-freezing protection method comprises the following steps: providing an auxiliary pipeline, a water pumping device and a heating device, wherein one end of the auxiliary pipeline is communicated with the water inlet pipeline, the other end of the auxiliary pipeline is communicated with the water outlet pipeline, and the water pumping device and the heating device are arranged on the auxiliary pipeline;
and controlling the opening or closing of the water pumping device and the heating device according to the state parameters of the water in the water outlet pipeline and/or the water inlet pipeline, wherein when the water pumping device and the heating device are in an opening state, the water in the water inlet pipeline and the water outlet pipeline circularly flows from the auxiliary pipeline to the evaporator and is heated in the auxiliary pipeline.
7. The method according to claim 6, wherein the state parameter of the water includes a water pressure difference between the water inlet pipe and the water outlet pipe, and when the air conditioner is operated, if the water pressure difference is smaller than a set value, the operation of the air conditioner is forcibly stopped, and the pumping means and the heating means are turned on.
8. The method according to claim 6, wherein the state parameters of the water further include a first water flow rate in the water inlet pipeline and/or the water outlet pipeline, when the air conditioning unit is operated, if the first water flow rate is smaller than a set value, the operation of the air conditioning unit is forcibly stopped, and at this time, if the pumping device and the heating device are in an operating state, the pumping device and the heating device are controlled to continuously operate for a preset period of time.
9. The method according to claim 6, wherein the state parameters of the water include water temperature in the water inlet pipeline and/or the water outlet pipeline, when the air conditioner is shut down, the water temperature in the water inlet pipeline and/or the water outlet pipeline is detected, and when the water temperature is less than or equal to a set value, the water pumping device and the heating device are started; and when the water temperature is greater than a set value, closing the water pumping device and the heating device.
10. The method of claim 9, wherein the water condition parameter further comprises a second water flow rate in the auxiliary pipeline, and when the water temperature reaches a condition of turning on the pumping device and the heating device, the pumping device and the heating device are turned on for a buffer time, and at this time, if the second water flow rate is smaller than a set value, the pumping device and the heating device are turned off.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311734618.6A CN117646949A (en) | 2023-12-15 | 2023-12-15 | Anti-freezing protection device and protection method for water-cooled air conditioning unit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311734618.6A CN117646949A (en) | 2023-12-15 | 2023-12-15 | Anti-freezing protection device and protection method for water-cooled air conditioning unit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117646949A true CN117646949A (en) | 2024-03-05 |
Family
ID=90043300
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202311734618.6A Pending CN117646949A (en) | 2023-12-15 | 2023-12-15 | Anti-freezing protection device and protection method for water-cooled air conditioning unit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117646949A (en) |
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2023
- 2023-12-15 CN CN202311734618.6A patent/CN117646949A/en active Pending
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