CONTROL METHOD AND CONTROL DEVICE FOR PREVENTING FALSE ALARM OF AN AIR CONDITIONER ANTI-OVERFLOW WATER LEVEL SWITCH

Description

PRIORITY CLAIM

This application claims benefit of Chinese Patent Application No. 202411067961.4, filed Aug. 5, 2024, and all the benefits accruing therefrom under 35 U.S.C. § 119, the contents of which in their entirety are herein incorporated by reference.

BACKGROUND

This application relates to the technical field of a refrigeration/cooling apparatus, in particular to a control method for preventing a false alarm of an air conditioner anti-overflow water level switch and a control device for executing the control method.

SUMMARY

This application aims to provide a control method for preventing a false alarm of an air conditioner water level switch so as to at least solve or alleviate some problems existing in the prior art.

This application provides a control method for preventing a false alarm of an air conditioner anti-overflow water level switch, an air conditioner, to which the control method is applicable, including a compressor, an indoor heat exchanger, an indoor fan, a condensed water receiving tray disposed corresponding to the indoor heat exchanger, an anti-overflow water level switch configured to detect a water level in the condensed water receiving tray in real time to be turned on/off and send an ON/OFF signal, and a drainage pump disposed corresponding to the condensed water receiving tray. The control method provided by this application includes an air conditioner operation mode determination step of determining whether the air conditioner is working in a predetermined mode; an anti-overflow water level switch OFF signal receiving step of receiving an OFF signal sent by the anti-overflow water level switch; a condensed-water generation volume calculation step of calculating, based on an indoor ambient humidity Rh detected in real time and rotation speed data of the indoor fan, a condensed water generation volume L₁ per unit time under a current working condition; a condensed-water alarm water level calculated time calculation step of calculating, based on volume data on the condensed water receiving tray and the condensed water generation volume L₁ per unit time, a calculated time t₁ required for condensed water to reach a position where the anti-overflow water level switch sends the OFF signal under the current working condition; an anti-overflow water level switch false alarm determination step of determining an operation condition of the compressor according to the ON/OFF signal of the anti-overflow water level switch after a specified time t₂ has elapsed since starting the drainage pump. The control method provided by this application includes an air conditioner operation mode determination step of determining whether the air conditioner is working in a predetermined mode; an anti-overflow water level switch OFF signal receiving step of receiving an OFF signal sent by the anti-overflow water level switch; a condensed-water generation volume calculation step of calculating, based on an indoor ambient humidity Rh detected in real time and rotation speed data of the indoor fan, a condensed water generation volume L₁ per unit time under a current working condition; a condensed-water alarm water level calculated time calculation step of calculating, based on volume data on the condensed water receiving tray and the condensed water generation volume L₁ per unit time, a calculated time t₁ required for condensed water to reach a position where the anti-overflow water level switch sends the OFF signal under the current working condition; a drainage pump control step of starting the drainage pump to operate at a maximum drainage volume L₂ after the calculated time t₁ has elapsed since receiving the OFF signal; and an anti-overflow water level switch false alarm determination step of determining an operation condition of the compressor according to the ON/OFF signal of the anti-overflow water level switch after a specified time t₂ has elapsed since starting the drainage pump.

In one or more embodiments, the predetermined mode in which the air conditioner operates is a cooling mode or a dehumidification mode.

In one or more embodiments, the compressor maintains normal operation until the operation condition of the compressor is determined in the anti-overflow water level switch false alarm determination step from a time when the OFF signal sent by the anti-overflow water level switch is received in the anti-overflow water level switch OFF signal receiving step.

In one or more embodiments, the calculated time t₁ conforms to the following numerical relationship:

t 1 = S × h 1 L 1 ,

where S is a bottom area of the condensed water receiving tray, and h₁ is a height position of a water receiving tray corresponding to the OFF signal sent by the anti-overflow water level switch.

In one or more embodiments, the specified time t₂ conforms to the following numerical relationship:

t 2 = S × ( h 1 - h 2 ) L 2 ,

where h₂ is a height position of the water receiving tray corresponding to an ON signal sent by the anti-overflow water level switch, and L₂ is a maximum drainage volume during operation of the drainage pump in the drainage pump control step.

In one or more embodiments, in the anti-overflow water level switch false alarm determination step, after the specified time t₂ has elapsed, when the anti-overflow water level switch sends the ON signal, it is determined that the OFF signal received in the anti-overflow water level switch OFF signal receiving step is a false alarm, and the compressor continues to operate, and when the anti-overflow water level switch sends the OFF signal, it is determined that the drainage pump or the anti-overflow water level switch fails, and the compressor is stopped.

In one or more embodiments, a distance A between an OFF position of the anti-overflow water level switch and the top of the condensed water receiving tray satisfies the following numerical relationship:

A > L 2 × t 2 S .

In one or more embodiments, the control method further includes: an emergency protection shutdown step, in which when the following numerical relationship is satisfied and an ON/OFF state of the anti-overflow water level switch does not change, the compressor immediately shuts down and sends an alarm signal: t₁+t₂>m×t₀, where t₀ is a time required for the condensed water receiving tray to be full of water when the indoor heat exchanger generates a maximum condensed water generation volume, and m is 0.8 to 0.9.

In one or more embodiments, the control method further includes: a drainage pump priority control step of, upon receiving the OFF signal sent by the anti-overflow water level switch in the anti-overflow water level switch OFF signal receiving step, preferentially starting the drainage pump to operate at a maximum drainage volume L₂ for a drainage duration t₃ and then stopping the drainage pump, in which the drainage duration t₃ satisfies the following

t 3 = S × h 1 L 2 - L 1 .

In one or more embodiments, a control device includes: an air conditioner operation mode determination module configured to determine whether the air conditioner is working in a predetermined mode; an anti-overflow water level switch OFF signal receiving module configured to receive an OFF signal sent by the anti-overflow water level switch; a condensed-water generation volume calculation module configured to calculate, based on an indoor ambient humidity Rh detected in real time and rotation speed data of the indoor fan, a condensed water generation volume L₁ per unit time under a current working condition; a condensed-water alarm water level calculated time calculation module configured to calculate, based on volume data on the condensed water receiving tray and the condensed water generation volume L₁ per unit time, a calculated time t₁ required for condensed water to reach a position where the anti-overflow water level switch sends the OFF signal under the current working condition; a drainage pump control module configured to start the drainage pump to operate at a maximum drainage volume L₂ after the calculated time t₁ has elapsed since receiving the OFF signal; and an anti-overflow water level switch false alarm determination module configured to determine an operation condition of the compressor according to the ON/OFF signal of the anti-overflow water level switch after a specified time t₂ has elapsed since starting the drainage pump.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is a schematic diagram of a partial structural of an air conditioner according to one or more embodiments of this application.

FIG. 2 is a schematic diagram of execution steps of a control method for preventing a false alarm of an air conditioner anti-overflow water level switch according to one or more embodiments of this application.

FIG. 3 is a schematic diagram of execution steps of a control method for preventing a false alarm of an air conditioner anti-overflow water level switch according to one or more embodiments of this application.

FIG. 4 is a schematic diagram of execution steps of a control method for preventing a false alarm of an air conditioner anti-overflow water level switch according to one or more embodiments of this application.

FIG. 5 is a schematic diagram of modules of a control device for preventing a false alarm of an air conditioner anti-overflow water level switch according to one or more embodiments of this application.

Reference numerals: Air conditioner 101, indoor heat exchanger 1, condensed water receiving tray 2, drainage pump 3, anti-overflow water level switch 4, anti-overflow water level switch ON signal position 41, anti-overflow water level switch OFF signal position 42, floating ball 43, control device 5, compressor 6, outdoor heat exchanger 7, expansion device 8, indoor fan 11, air conditioner operation mode determination module 51, anti-overflow water level switch OFF signal receiving module 52, condensed-water generation volume calculation module 53, condensed-water alarm water level calculated time calculation module 54, drainage pump control module 55, anti-overflow water level switch false alarm determination module 56, air conditioner operation mode determination step S1, anti-overflow water level switch OFF signal receiving step S2, condensed-water generation volume calculation step S3, condensed-water alarm water level calculated time calculation step S4, drainage pump control step S5, anti-overflow water level switch false alarm determination step S6, emergency protection shutdown step S7, and drainage pump priority control step S8.

DETAILED DESCRIPTION OF THE DISCLOSURE

It should be noted that working principles, features, advantages, and the like of a refrigeration apparatus according to this application will be explained below by way of embodiments. However, it should be understood that all descriptions are only given for exemplification and therefore these embodiments should not be understood as forming any limitation on this application.

In addition, for any single technical feature described or implicit in the embodiments mentioned herein, or any single technical feature shown or implicit in the drawings, this application still allows any combination or deletion between these technical features (or their equivalents) without any technical obstacles, thereby obtaining more other embodiments of this application that may not be directly mentioned herein.

An air conditioner may provide a cooling or heating effect for an indoor environment to provide a comfortable indoor environment. In a cooling mode, condensed water is generated inside the air conditioner, and due to a drainage height, a drainage pump needs to be used for drainage sometimes. In order to prevent the condensed water of the air conditioner from overflowing a condensed water receiving tray when the drainage pump fails, the air conditioners are typically equipped with an anti-overflow water level switch. In existing systems, after the air conditioner has been used for a long time, the water level switch may become scaled, causing a floating ball to stick slightly at a scaled position and result in a false alarm from the water level switch, which in turn triggers a protection mechanism of a main control unit of an air conditioner, causes unnecessary shutdown, and affects a user experience.

This application aims to provide a control method for preventing a false alarm of an air conditioner anti-overflow water level switch so as to at least solve or alleviate some of these problems.

FIG. 1 is a schematic structural diagram of an air conditioner according to one or more embodiments of this application, and referring to FIG. 1, an air conditioner 101 according to some embodiments includes an indoor heat exchanger 1, an outdoor heat exchanger 7, an expansion device 8, a condensed water receiving tray 2, a drainage pump 3, an anti-overflow water level switch 4, and a floating ball 43.

As illustrated in FIG. 1, when air conditioner 101 operates in a cooling or dehumidification mode, the refrigerant discharged from the compressor 6 flows through the refrigerant piping to the outdoor heat exchanger 7. In the outdoor heat exchanger 7, it undergoes heat exchange and condensation with the heat exchange medium. The condensed refrigerant then continues to flow to the expansion device 8 where it is throttled and expanded. The refrigerant leaving the expansion device 8 enters the indoor heat exchanger 1, where it undergoes heat exchange and evaporation with the heat exchange medium. The evaporated refrigerant then returns to the compressor 1, thereby completing the refrigeration cycle. The condensed water receiving tray 2 is disposed below the indoor heat exchanger 1 to receive condensed water from the indoor heat exchanger 1. The drainage pump 3 is disposed corresponding to the condensed water receiving tray 2, and the condensed water accumulated in the condensed water receiving tray 2 is discharged to the outside of the air conditioner 101 through the operation of the drainage pump 3. The anti-overflow water level switch 4 is further provided corresponding to the condensed water receiving tray 2. The expansion device 8 may be an expansion valve or any equivalent thereof.

In general, in a case where a water level of the condensed water in the condensed water receiving tray 2 changes and a position of the floating ball 43 changes accordingly with the change of the water level, when the floating ball 43 is located at or below an anti-overflow water level switch ON signal position 41, the anti-overflow water level switch 4 is turned on and sends an ON signal, and when the floating ball 43 is located at or above an anti-overflow water level switch OFF signal position 42, the anti-overflow water level switch 4 is turned off and sends an OFF signal.

Specifically, the anti-overflow water level switch ON signal position 41 is set at a distance h₂ from the bottom of the condensed water receiving tray 2, and the anti-overflow water level switch OFF signal position 42 is set at a distance h₁ from the bottom of the condensed water receiving tray 2. The floating ball 43 is matched with the anti-overflow water level switch 4, and rises or falls along with a water level of the condensed water in the condensed water receiving tray 2. When the floating ball 43 is located between the bottom of the condensed water receiving tray 2 and the anti-overflow water level switch ON signal position 41, the anti-overflow water level switch 4 has a current in an ON state and sends an ON signal, that is, h₂ is a height position of the water receiving tray corresponding to the ON signal sent by the anti-overflow water level switch 4. When the floating ball 43 reaches the anti-overflow water level switch OFF signal position 42 or a higher position, the anti-overflow water level switch 4 has a current in an OFF state and sends an OFF signal, that is, h₁ is a height position of the water receiving tray corresponding to the OFF signal sent by the anti-overflow water level switch 4.

When the anti-overflow water level switch 4 is turned off (that is, the OFF signal is sent), a main control unit of the air conditioner triggers an alarm of the anti-overflow water level switch 4 upon receiving the OFF signal.

Here, h₁ is greater than h₂, and preferably h₁ is greater than h₂ by 2 to 3 mm, that is, a distance between the anti-overflow water level switch ON signal position 41 and the anti-overflow water level switch OFF signal position 42 is 2 to 3 mm. In this way, this situation can be prevented that the water level of the condensed water fluctuates due to vibrations when the drainage pump is turned on, causing the floating ball 43 to swing back and forth between the anti-overflow water level switch ON signal position 41 and the anti-overflow water level switch OFF signal position 42 due to the water level fluctuations, causing the anti-overflow water level switch 4 to frequently turn on or off, and triggering unnecessary alarms of the anti-overflow water level switch.

FIG. 2 is a schematic diagram of execution steps of a control method for preventing a false alarm of an air conditioner anti-overflow water level switch according to one or more embodiments of this application. As illustrated in FIG. 2, the control method for preventing a false alarm of an air conditioner water level switch according to some embodiments includes: an air conditioner operation mode determination step S1; an anti-overflow water level switch OFF signal receiving step S2; a condensed-water generation volume calculation step S3; a condensed-water alarm water level calculated time calculation step S4; a drainage pump control step S5; and an anti-overflow water level switch false alarm determination step S6.

In some embodiments of this application, when the air conditioner 101 is started to operate, the air conditioner operation mode determination step S1 is executed to detect a current operation mode of the air conditioner 101. When it is detected that the air conditioner 101 currently operates in a cooling or dehumidification mode, the anti-overflow water level switch OFF signal receiving step S2 is executed, that is, a signal of the anti-overflow water level switch is received in real time. Upon receiving an OFF signal sent by the anti-overflow water level switch 4, the condensed-water generation volume calculation step S3 is executed to calculate, based on an indoor ambient humidity Rh detected in real time and rotation speed data on an indoor fan 11, a condensed water generation volume L₁ per unit time under a current working condition. Further, the condensed-water alarm water level calculated time calculation step S4 is executed to calculate, based on volume data on the condensed water receiving tray 2 and the condensed water generation volume L₁ per unit time, a calculated time t₁ required for the water level of the condensed water to rise from the bottom of the condensed water receiving tray 2 to the anti-overflow water level switch OFF signal position 42 under the current working condition after the air conditioner 101 is started to operate.

Considering that the OFF signal of the anti-overflow water level switch may be a false alarm caused by the scaling of the anti-overflow water level switch 4 causing the floating ball 43 to get stuck, the actual water level of the condensed water in the condensed water receiving tray 2 cannot be detected through the floating ball 43. In general, when the air conditioner 101 is started to operate, no condensed water is generated in the indoor heat exchanger 1, and no condensed water is temporarily accumulated in the condensed water receiving tray 2. At this time, when the OFF signal of the anti-overflow water level switch is received in the anti-overflow water level switch OFF signal receiving step S2, it can be determined that no condensed water is accumulated in the condensed water receiving tray 2, and based on the determination, the air conditioner 101 is controlled to continue normal operation for the calculated time t₁ and the drainage pump 3 is not turned on.

When the air conditioner 101 is started to operate and the calculated time t₁ has elapsed since receiving the OFF signal, the water level in the condensed water receiving tray 2 has theoretically reached the anti-overflow water level switch OFF signal position 42. At this time, in the case where the OFF signal of the anti-overflow water level switch may be a false alarm caused by the scaling of the anti-overflow water level switch 4 causing the floating ball 43 to get stuck at a certain position, after the air conditioner 101 operates for the calculated time t₁, when the water level of the condensed water in the condensed water receiving tray 2 rises to the stuck position of the floating ball 43, buoyancy is generated on the floating ball 43, thereby pushing the floating ball 43 to leave the stuck position.

After the calculated time t₁ has elapsed since receiving the OFF signal, the drainage pump control step S5 is executed to start the drainage pump 3 to operate at a maximum drainage volume L₂, so as to pump out the condensed water in the condensed water receiving tray 2 to the outside of the air conditioner 101 as soon as possible. After the drainage pump 3 is started for a specified time t₂, the anti-overflow water level switch false alarm determination step S6 is executed to determine whether a compressor 6 continues to operate according to whether the signal of the anti-overflow water level switch acquired in real time is an ON signal or an OFF signal.

Specifically, when the floating ball 43 falls to the anti-overflow water level switch ON signal position 41 or a position lower than the anti-overflow water level switch ON signal position 41 after the specified time t₂ has elapsed, that is, after the drainage pump 3 has continuously drained the water for the specified time t₂, the anti-overflow water level switch 4 is turned on and sends an ON signal. At this time, in the anti-overflow water level switch false alarm determination step S6, it is determined that the floating ball 43 falls to the anti-overflow water level switch ON signal position 41 or a position lower than the anti-overflow water level switch ON signal position 41 according to the received ON signal, and accordingly, it is determined that the OFF signal received in the previous anti-overflow water level switch OFF signal receiving step S2 is caused by slight sticking of the floating ball 43. The reason is that since the air conditioner 101 operates for the calculated time t₁, the condensed water generated within the calculated time t₁ is accumulated in the condensed water receiving tray 2 and the water level thereof rises, and a pushing force of the rising water level causes the floating ball 43 to escape from the stuck position. Moreover, the drainage pump 3 is started to drain the condensed water in the condensed water receiving tray 2 to the outside of the air conditioner 101, and at this time, the floating ball 43 escaping from the stuck position falls along with the water level of the condensed water. In the anti-overflow water level switch false alarm determination step S6, it is determined that the air conditioner 101 can continue to operate without shutting down.

On the contrary, when the anti-overflow water level switch 4 is still in the off state and continues to send an OFF signal after the specified time t₂ has elapsed, it is determined that the OFF signal received in the previous anti-overflow water level switch OFF signal receiving step S2 is not caused by the sticking of the floating ball 43, but may be caused by a failure of the drainage pump 3 or the anti-overflow water level switch 4, which makes it impossible to drain water normally or give an alarm normally. At this time, in the anti-overflow water level switch false alarm determination step S6, the compressor 6 is controlled to stop operating accordingly to prevent the condensed water continuously generated in the indoor heat exchanger 1, causing a condensed water volume in the condensed water receiving tray 2 to exceed a maximum condensed water volume and overflow to the outside of the condensed water receiving tray 2.

In some embodiments, the condensed-water generation volume calculation step S3 is executed to calculate the condensed water generation volume L₁ per unit time based on the indoor ambient humidity Rh detected in real time and the rotation speed data of the indoor fan, but this application is not limited thereto. Other methods of calculating the condensed water generation volume L₁ per unit time, such as calculating the condensed water generation volume L₁ per unit time based on the previous same or similar working conditions, or based on a refrigeration capacity of the air conditioner 101, a set room temperature, and humidity data in the weather forecast, all fall within the scope of protection of this application.

In some embodiments, the condensed-water alarm water level calculated time calculation step S4 is executed to calculate, based on volume data on the condensed water receiving tray 2 and the condensed water generation volume L₁ per unit time, the calculated time t₁ required for the condensed water to reach a position where the anti-overflow water level switch sends the OFF signal under the current working condition, that is, the floating ball 43 to rise from a lowest position of the condensed water receiving tray 2 to the anti-overflow water level switch OFF signal position 42. However, the calculated time t₁ may also be a calculated time when the floating ball 43 rises from the lowest position of the condensed water receiving tray 2 to a certain preset position or set height instead of the anti-overflow water level switch OFF signal position 42, and the preset position or set height may be predetermined based on the refrigeration capacity of the air conditioner 101, an average condensed water volume generated under a refrigeration working condition in the previous period, the humidity data in the weather forecast, and the like.

Therefore, according to some embodiments of this application, upon receiving an OFF signal of the anti-overflow water level switch during operation, the air conditioner 101 does not need to shut down immediately. By executing the condensed-water generation volume calculation step S3, the condensed-water alarm water level calculated time calculation step S4 and the drainage pump control step S5, the water level in the condensed water receiving tray 2 is changed, driving the floating ball 43 to rise or fall, to determine whether the OFF signal of the anti-overflow water level switch is caused by slight scaling, or the like, which causes the floating ball 43 to be stuck in the anti-overflow water level switch OFF signal position 42, thereby identifying and determining whether the anti-overflow water level switch 4 generates a false alarm, and avoiding the problem that the air conditioner 101 is immediately triggered to shut down for protection upon receiving the OFF signal of the anti-overflow water level switch, which affects the user experience.

In some embodiments of this application, the compressor 6 maintains normal operation until an operation condition of the compressor 6 is determined in the anti-overflow water level switch false alarm determination step S6 from the time when the OFF signal sent by the anti-overflow water level switch 4 is received in the anti-overflow water level switch OFF signal receiving step S2.

According to the above embodiment, after the air conditioner 101 is started, even if the OFF signal sent by the anti-overflow water level switch 4 is received, the compressor 6 still maintains normal operation. Further, when the false alarm is caused by the sticking of the floating ball 43, the compressor 6 maintains normal operation, so that the indoor heat exchanger 1 continues to operate to generate condensed water, the water level of the condensed water in the condensed water receiving tray 2 rises, and thus the floating ball 43 is pushed to rise and leave the stuck position. In addition, this avoids the problem of unnecessary start-stop of the compressor 6, which affects the user experience, the unnecessary start-stop of the compressor 6 being caused by the compressor 6 stopping immediately when the anti-overflow water level switch alarms and then starting up again after manual detection as a false alarm.

Preferably, the calculated time t₁ conforms to the following numerical relationship:

t 1 = S × h 1 L 1 ,

where S is a bottom area of the condensed water receiving tray 2, and h₁ is the height position of the water receiving tray corresponding to the OFF signal sent by the anti-overflow water level switch 4. The specified time t₂ conforms to the following numerical relationship:

t 2 = S × ( h 1 - h 2 ) L 2 ,

where h₂ is the height position of the water receiving tray corresponding to the ON signal sent by the anti-overflow water level switch 4, and L₂ is the maximum drainage volume during operation of the drainage pump in the drainage pump control step S5.

In this way, the set calculated time t₁ is calculated based on a ratio of a volume of condensed water that can be accommodated between the bottom of the condensed water receiving tray 2 and the anti-overflow water level switch OFF signal position 42 to the condensed water generation volume L₁ per unit time. When the air conditioner 101 is started to operate, upon receiving the OFF signal in the anti-overflow water level switch OFF signal receiving step S2, the water level of the condensed water generated by the indoor heat exchanger 1 that continues to operate and accumulated in the condensed water receiving tray 2 can rise from the bottom of the condensed water receiving tray 2 to the anti-overflow water level switch OFF signal position 42, thereby avoiding the problem that the floating ball 43 cannot escape from the stuck position when the water level is lower than the anti-overflow water level switch OFF signal position 42, or the condensed water overflows the condensed water receiving tray 2 due to an overhigh water level.

The specified time t₂ is set based on a ratio of a volume of condensed water that can be accommodated between the anti-overflow water level switch ON signal position 41 and the anti-overflow water level switch OFF signal position 42 to the maximum drainage volume L₂ when the drainage pump 3 operates. At this time, when the signal sent by the anti-overflow water level switch 4 is the false alarm caused by the sticking of the floating ball 43, the water level of the condensed water in the condensed water receiving tray 2 can be lowered within the shortest time, and the rapid change of the water level causes the floating ball 43 to escape from the stuck position until the anti-overflow water level switch ON signal position 41, thereby facilitating the determination of a false alarm in the subsequent anti-overflow water level switch false alarm determination step S6 and maintaining a normal operation mode of the air conditioner 101. On the other hand, when the anti-overflow water level switch 4 gives a true alarm, that is, the water level of the condensed water does exceed the anti-overflow water level switch OFF signal position 42, the drainage pump 3 can also be driven to drain water within the shortest time, thereby preventing excessive accumulation of the condensed water in the condensed water receiving tray 2 from causing overflow.

In some embodiments, a distance A between the anti-overflow water level switch OFF signal position 42 of the anti-overflow water level switch 4 and the top of the condensed water receiving tray 2 satisfies the following numerical relationship:

A > L 2 × t 2 S .

Through the above embodiment, the distance between the anti-overflow water level switch OFF signal position 42 and the top of the condensed water receiving tray 2 is A, and A is greater than a ratio of the maximum drainage volume of the drainage pump 3 to a bottom area of the condensed water receiving tray 2 within the specified time t₂. When an alarm signal sent by the anti-overflow water level switch 4 is a true alarm caused by the failure of the drainage pump 3, even after the water level of the condensed water reaches the anti-overflow water level switch OFF signal position 42, the water level of the condensed water within the specified time t₂ continuously rises due to the failure of the drainage pump 3, but the water level of the condensed water does not exceed the top of the condensed water receiving tray 2, causing the overflow of the condensed water.

A specific length of the distance A between the anti-overflow water level switch OFF signal position 42 and the top of the condensed water receiving tray 2 can also be flexibly set according to refrigeration capacity of the air conditioner 101, a model of the drainage pump, a shape of the condensed water receiving tray 2 and the like. Any setting that can prevent the water level of the condensed water from exceeding the top of the condensed water receiving tray 2 and causing overflow of the condensed water when the drainage pump 3 fails falls within the scope of protection of this application.

A control method for preventing a false alarm of an air conditioner water level switch according to the second embodiment of this application is described using the same names or symbols as those in the control method for preventing the false alarm of the air conditioner anti-overflow water level switch in the above embodiment of this application, which pertain to the same content and will not be repeated here.

FIG. 3 is a schematic diagram of execution steps of a control method for preventing a false alarm of an air conditioner anti-overflow water level switch according to one or more embodiments of this application. Referring to FIG. 3, the control method for preventing a false alarm of an air conditioner anti-overflow water level switch in some embodiments further includes an emergency protection shutdown step S7.

Considering that the calculation or experimental results of the calculated time t₁ or the specified time t₂ under different working conditions may have deviations, in order to further prevent the condensed water from overflowing the condensed water receiving tray 2, assuming that the time required for the condensed water receiving tray 2 to be full of water when the indoor heat exchanger 1 generates a maximum condensed water generation volume is set as t₀, when t₁+t₂>m×t₀ and an ON/OFF signal of the anti-overflow water level switch does not change, the emergency protection shutdown step S7 is executed, and the compressor 6 is immediately shut down and sends an alarm signal.

Different n values can be flexibly set according to the sizes of different condensed water receiving trays 2. Any setting capable of preventing the overflow of the condensed water due to the maximum condensed water generation volume exceeding a maximum water storage volume of the condensed water receiving tray 2 shall fall within the scope of protection of this application, and preferably, in some embodiments, n is 0.8 to 0.9.

In a case where the condensed water generation volume L₁ per unit time increases due to a high indoor ambient humidity or other working conditions, when the drainage pump 3 fails and cannot drain water normally, the condensed water volume accumulated in the condensed water receiving tray 2 may exceed the maximum water storage volume of the condensed water receiving tray 2, causing the overflow of the condensed water, after the air conditioner 101 operates for the theoretical time t₁ and the specified time t₂. When the formula is satisfied and an ON/OFF state of the anti-overflow water level switch 4 does not change, regardless of the current step or working condition, the emergency protection shutdown step S7 is preferentially executed to control the compressor 6 to shut down immediately and send an alarm signal, thereby preventing the condensed water from overflowing the condensed water receiving tray 2 and affecting the air conditioner 101.

A control method for preventing a false alarm of an air conditioner anti-overflow water level switch according to the third embodiment of this application is described using the same names or symbols as those in the control method for preventing the false alarm of the air conditioner anti-overflow water level switch in the above embodiment of this application, which pertain to the same content and will not be repeated here.

FIG. 4 is a schematic diagram of execution steps of a control method for preventing a false alarm of an air conditioner anti-overflow water level switch according to one or more embodiments of this application. Referring to FIG. 4, the control method for preventing a false alarm of an air conditioner anti-overflow water level switch in some embodiments further includes a drainage pump priority control step S8.

Considering the situation that the anti-overflow water level switch 4 sends an alarm signal (that is, an OFF signal) during the use of the air conditioner 101, at this time, the air conditioner 101 has been operated for a period of time, a certain amount of condensed water may be stored in the condensed water receiving tray 2, and when the operation of the air conditioner 101 is not stopped but the air conditioner operation mode determination step S1, the anti-overflow water level switch OFF signal receiving step S2, the condensed-water generation volume calculation step S3, the condensed-water alarm water level calculated time calculation step S4, the drainage pump control step S5 and the anti-overflow water level switch false alarm determination step S6 continue to be executed according to the control method in the first embodiment, there is a risk that the condensed water has overflowed the condensed water receiving tray 2 before determining whether the alarm signal is a false alarm.

In order to avoid the above situation, in some embodiments, when the OFF signal sent by the anti-overflow water level switch 4 is received in the anti-overflow water level switch OFF signal receiving step S2 after the air conditioner 101 has operated for a specified time, on the premise that the air conditioner 101 continues to operate, the drainage pump control step S5 is not executed, but the drainage pump priority control step S8 is preferentially executed to control the drainage pump 3 to operate at the maximum drainage volume L₂ for a drainage duration t₃ and then stop the drainage pump 3. That is, when the OFF signal is received in the anti-overflow water level switch OFF signal receiving step S2 during the operation of the air conditioner 101, the drainage pump 3 is preferentially started to drain the condensed water in the condensed water receiving tray 2, then the drainage pump 3 stops operating, and the drainage pump control step S5 is resumed after the drainage pump 3 stops operating for the calculated time t₁.

Preferably, the drainage duration t₃ satisfies the following formula:

t 3 = S × h 1 L 2 - L 1 .

The drainage duration t₃ is a ratio of a water storage volume of the condensed water receiving tray 2 between the bottom of the condensed water receiving tray 2 and the anti-overflow water level switch OFF signal position 42 to a difference between the maximum drainage volume during operation of the drainage pump 3 and the condensed water generation volume L₁ per unit time (that is, a condensed water volume discharged from the condensed water receiving tray 2 to the outside of the air conditioner 101 per unit time).

In this way, when the OFF signal sent by the anti-overflow water level switch 4 is received in the anti-overflow water level switch OFF signal receiving step S2 during the operation of the air conditioner 101, in other words, the OFF signal sent by the anti-overflow water level switch 4 is received in the anti-overflow water level switch OFF signal receiving step S2 after the air conditioner 101 has been started and continuously operated for a period of time, considering that some condensed water has already accumulated in the condensed water receiving tray 2 at this time, the drainage pump priority control step S8 is executed to control the drainage pump 3 to operate preferentially for the drainage duration t₃, so that the condensed water accumulated in the condensed water receiving tray 2 can be discharged completely theoretically. This avoids the possibility that after the calculated time t₁ has elapsed, the condensed water volume may exceed the maximum water storage volume of the condensed water receiving tray 2, causing the overflow of the condensed water. Meanwhile, the situations are avoided that the condensed water in the condensed water receiving tray 2 is accumulated with the condensed water generated after the calculated time t₁, the water level of the condensed water exceeds the anti-overflow water level switch ON signal position 41, which affects the determination of whether the alarm of the water level switch is a false alarm, and leads to determining a false alarm as a true alarm and triggering unnecessary shutdown protection.

The drainage duration t₃ in the drainage pump priority control step S8 and may also be calculated based on an operation duration of the air conditioner 101, the condensed water generation volume related to the working condition of the air conditioner 101, an actual drainage volume of the drainage pump 3, and other data, which is not limited to the calculation formula in some embodiments.

A control device for preventing a false alarm of an air conditioner anti-overflow water level switch according to the fourth embodiment of this application is described using the same names or symbols as those in the control method for preventing the false alarm of the air conditioner anti-overflow water level switch in the above embodiment of this application, which pertain to the same content and will not be repeated here.

FIG. 5 is a schematic diagram of modules of a control device for preventing a false alarm of an air conditioner anti-overflow water level switch according to one or more embodiments of this application. As illustrated in FIG. 5, the control device 5 for preventing a false alarm of an air conditioner anti-overflow water level switch according to some embodiments includes: an air conditioner operation mode determination module 51; an anti-overflow water level switch OFF signal receiving module 52; a condensed-water generation volume calculation module 53; a condensed-water alarm water level calculated time calculation module 54; a drainage pump control module 55; and an anti-overflow water level switch false alarm determination module 56.

In some embodiments of this application, when the air conditioner 101 is started to operate, the air conditioner operation mode determination module 51 is operated to detect a current operation mode of the air conditioner 101. When it is detected that the air conditioner 101 currently operates in a cooling or dehumidification mode, the anti-overflow water level switch OFF signal receiving module 52 is operated, that is, a signal of the anti-overflow water level switch is received in real time. Upon receiving an OFF signal sent by the anti-overflow water level switch 4, the condensed-water generation volume calculation module 53 is operated to calculate, based on an indoor ambient humidity Rh detected in real time and rotation speed data on an indoor fan, a condensed water generation volume L₁ per unit time under a current working condition. Further, the condensed-water alarm water level calculated time calculation module 54 is operated to calculate, based on volume data on the condensed water receiving tray 2 and the condensed water generation volume L₁ per unit time, a calculated time t₁ required for the water level of the condensed water to rise from the bottom of the condensed water receiving tray 2 to the anti-overflow water level switch OFF signal position 42 under the current working condition after the air conditioner 101 is started to operate.

After the calculated time t₁ has elapsed since receiving the OFF signal, the drainage pump control module 55 is operated to start the drainage pump 3 to operate at a maximum drainage volume L₂, so as to pump out the condensed water in the condensed water receiving tray 2 to the outside of the air conditioner 101 as soon as possible. After the drainage pump 3 is started for a specified time t₂, the anti-overflow water level switch false alarm determination module 56 is operated to determine whether a compressor 6 continues to operate according to whether the signal of the anti-overflow water level switch acquired in real time is an ON signal or an OFF signal.

In some embodiments, the air conditioner operation mode determination module 51 controls the execution of the air conditioner operation mode determination step S1, the anti-overflow water level switch OFF signal receiving module 52 controls the execution of the anti-overflow water level switch OFF signal receiving step S2, the condensed-water generation volume calculation module 53 controls the execution of the condensed-water generation volume calculation step S3, the condensed-water alarm water level calculated time calculation module 54 controls the execution of the condensed-water alarm water level calculated time calculation step S4, the drainage pump control module 55 controls the execution of the drainage pump control step S5, and the anti-overflow water level switch false alarm determination module 56 controls the execution of the anti-overflow water level switch false alarm determination step S6.

The above embodiments are merely preferred embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of this application shall be included in the protection scope of this application.