A method for detecting the cleaning requirements of an air conditioner indoor heat exchanger and an air conditioner

Abstract

This invention provides a method for detecting the cleaning needs of an indoor heat exchanger in an air conditioner, and an air conditioner comprising an indoor casing; an indoor air duct connecting an indoor air inlet and an indoor air outlet is formed inside the indoor casing, and an indoor heat exchanger is disposed within the indoor air duct; the cleaning needs detection method includes: controlling the air conditioner to a cleaning needs detection state, acquiring the inlet air temperature at the indoor air inlet and the outlet air temperature at the indoor air outlet, calculating the inlet-outlet temperature difference between the inlet and outlet air temperatures, and determining whether the indoor heat exchanger needs cleaning based on the inlet-outlet temperature difference; it can intelligently and accurately determine whether the indoor heat exchanger needs cleaning, thereby enabling timely cleaning of the indoor heat exchanger, ensuring its cleanliness, and improving its heat exchange capacity; it requires no sensors and has a simple structure.

Description

Technical Field

[0001] This invention belongs to the field of heat exchanger technology, and particularly relates to a method for detecting the cleaning requirements of an indoor heat exchanger in an air conditioner and an air conditioner. Background Technology

[0002] After an air conditioner has been in use for a period of time, dust will accumulate on the indoor heat exchanger. A large amount of dust accumulation increases air resistance, reduces the heat exchanger's thermal conductivity, and causes a decrease in cooling efficiency and energy waste. Furthermore, prolonged dust accumulation can breed bacteria, affecting indoor air quality and user health. Most air conditioners on the market currently have self-cleaning functions. Some require users to manually assess the dirt level of the indoor heat exchanger and activate the self-cleaning function, leading to delayed cleaning and poor heat exchange efficiency. Others use the air conditioner's intelligent system to determine the dirt level of the indoor heat exchanger and activate the self-cleaning function, but this requires carefully placed sensors, increasing costs. Summary of the Invention

[0003] In view of this, the present invention provides a method for detecting the cleaning needs of an indoor heat exchanger and an air conditioner, to solve the problems in the prior art where users judge the dirt status of the indoor heat exchanger themselves, resulting in untimely cleaning of the indoor heat exchanger and poor heat exchange effect, and where the air conditioner needs to arrange additional sensors to intelligently judge the dirt status of the indoor heat exchanger, resulting in complex structure and high cost.

[0004] According to a first aspect of the embodiments of this application, a method for detecting the cleaning requirements of an indoor heat exchanger in an air conditioner is provided. The air conditioner includes an indoor casing, the casing wall of which forms an indoor air inlet and an indoor air outlet. An indoor air duct communicating with the indoor air inlet and the indoor air outlet is formed inside the indoor casing, and the indoor heat exchanger is disposed within the indoor air duct. The cleaning requirements detection method includes:

[0005] The air conditioner is controlled to be in a state of cleaning requirement detection;

[0006] Obtain the air inlet temperature of the indoor air inlet and the air outlet temperature of the indoor air outlet;

[0007] Calculate the temperature difference between the inlet and outlet air temperatures;

[0008] Based on the temperature difference between the inlet and outlet air, determine whether the indoor heat exchanger needs cleaning;

[0009] The air conditioner's operating mode includes at least one of a cooling mode and a heating mode; when the air conditioner is in a cleaning demand detection state, the air conditioner operates according to parameters related to the operating mode.

[0010] When the air conditioner is in the cooling mode, the temperature difference between the inlet and outlet air is equal to the inlet air temperature minus the outlet air temperature; when the air conditioner is in the heating mode, the temperature difference between the inlet and outlet air is equal to the outlet air temperature minus the inlet air temperature.

[0011] Using this embodiment, it is possible to intelligently and accurately determine whether the indoor heat exchanger needs cleaning, and thus clean the indoor heat exchanger in a timely manner, ensuring the cleanliness of the indoor heat exchanger, improving the heat exchange capacity of the indoor heat exchanger, and preventing bacteria from growing on the surface of the indoor heat exchanger; no sensors are required, the structure is simple, and no additional cost is added;

[0012] In conjunction with the first aspect, in an optional implementation of this application embodiment, determining whether the indoor heat exchanger needs cleaning based on the inlet and outlet air temperature difference includes:

[0013] Calculate the difference between the inlet and outlet air temperature difference and the preset temperature difference;

[0014] Based on the difference between the inlet and outlet air temperature difference and the preset temperature difference, determine whether the indoor heat exchanger needs cleaning;

[0015] The preset temperature difference is determined based on the air conditioner's operating mode, the indoor ambient temperature before the air conditioner enters the detection state, and the outdoor ambient temperature.

[0016] In conjunction with the first aspect, in an optional implementation of this application embodiment, determining whether the indoor heat exchanger needs cleaning based on the difference between the inlet and outlet air temperature difference and a preset temperature difference includes:

[0017] When the value of the preset temperature difference minus the inlet and outlet air temperature difference is greater than the preset temperature, it is determined that the indoor heat exchanger needs to be cleaned.

[0018] When the value of the preset temperature difference minus the inlet and outlet air temperature difference is less than or equal to the preset temperature, it is determined that the indoor heat exchanger does not need to be cleaned.

[0019] In conjunction with the first aspect, in an optional implementation of this application embodiment, controlling the air conditioner to be in a cleaning demand detection state includes:

[0020] Determine the mode in which the air conditioner last operated;

[0021] Determine the operating parameters based on the previous operating mode;

[0022] Control the air conditioner to be in the previous operating mode and control the air conditioner to operate with the operating parameters.

[0023] In conjunction with the first aspect, in one optional implementation of this application embodiment, the air conditioner includes an indoor fan, an outdoor fan, and a compressor, a four-way valve, an indoor heat exchanger, a throttling device, and an outdoor heat exchanger connected sequentially via refrigerant piping; controlling the air conditioner to be in the previous operating mode and controlling the air conditioner to operate with the operating parameters includes:

[0024] When the air conditioner was previously in cooling mode, the air conditioner is controlled to be in cooling mode, and the compressor is controlled to run at a preset frequency. The four-way valve is in a power-off state, the indoor fan runs at a preset indoor fan speed, the throttling device is in a preset opening degree, and the outdoor fan runs at a preset outdoor fan speed.

[0025] When the air conditioner was previously in heating mode, the air conditioner is controlled to be in heating mode, and the compressor is controlled to run at a preset frequency. The four-way valve is powered on, the indoor fan runs at a preset indoor fan speed, the throttling device is at a preset opening, and the outdoor fan runs at a preset outdoor fan speed.

[0026] In conjunction with the first aspect, in an optional implementation of this application embodiment, the step of controlling the air conditioner to enter the cleaning demand detection state further includes:

[0027] Determine whether the time since the last cleaning of the indoor heat exchanger of the air conditioner is greater than a second preset time.

[0028] When the time since the last cleaning of the indoor heat exchanger by the air conditioner is less than or equal to the second preset time, the air conditioner is controlled not to perform the cleaning requirement detection.

[0029] If the time since the last cleaning of the indoor heat exchanger is longer than the second preset time, it is determined whether the air conditioner is currently running.

[0030] Based on the determination of whether the air conditioner is running, control the air conditioner to perform or not perform cleaning requirement detection.

[0031] In conjunction with the first aspect, in an optional implementation of this application embodiment, controlling the air conditioner to perform or not perform cleaning requirement detection based on the determination result of whether the air conditioner is running includes:

[0032] When the air conditioner is running, after the current operation of the air conditioner is completed, control the air conditioner to perform a cleaning demand detection;

[0033] When the air conditioner is not running, control the air conditioner to perform a cleaning requirement detection.

[0034] In conjunction with the first aspect, in an optional implementation of the embodiments of this application, the cleaning requirement detection method further includes:

[0035] When it is determined that the indoor heat exchanger needs to be cleaned, after the cleaning of the indoor heat exchanger is completed, the time elapsed since the last cleaning of the indoor heat exchanger is initialized to zero and the timer is restarted.

[0036] When it is determined that the indoor heat exchanger does not need to be cleaned, a new second preset duration is determined as t' = k * t2, where k is a coefficient that satisfies: 0.4 ≤ k ≤ 0.6;

[0037] Where t2 is the second preset duration.

[0038] In conjunction with the first aspect, in an optional implementation of this application embodiment, the operating mode of the air conditioner, the relationship between the indoor ambient temperature and the preset indoor ambient temperature, the relationship between the outdoor ambient temperature and the preset outdoor ambient temperature, and the preset temperature difference have a preset corresponding relationship; the method for determining the preset temperature difference includes:

[0039] Compare the indoor ambient temperature with the preset indoor ambient temperature, and the outdoor ambient temperature with the preset outdoor ambient temperature;

[0040] Determine the relationship between the indoor ambient temperature and the preset indoor ambient temperature, and the relationship between the outdoor ambient temperature and the preset outdoor ambient temperature;

[0041] The preset temperature difference is determined based on the air conditioner's operating mode, the relationship between the indoor ambient temperature and the preset indoor ambient temperature, the relationship between the outdoor ambient temperature and the preset outdoor ambient temperature, and the preset correspondence.

[0042] According to a second aspect of the present application, an air conditioner is provided, including an indoor casing, an indoor fan, an outdoor fan, and a compressor, a four-way valve, an indoor heat exchanger, a throttling device, and an outdoor heat exchanger connected in sequence via refrigerant piping; the shell wall of the indoor casing has an indoor air inlet and an indoor air outlet, and the interior of the indoor casing has an indoor air duct connecting the indoor air inlet and the indoor air outlet, and the indoor fan and the indoor heat exchanger are disposed in the indoor air duct;

[0043] The air conditioner uses any of the above-described methods for detecting the cleaning requirements of the indoor heat exchanger to determine whether the indoor heat exchanger needs to be cleaned.

[0044] Using this method, it is possible to intelligently and accurately determine whether the indoor heat exchanger needs cleaning, thereby enabling timely cleaning of the indoor heat exchanger, improving its heat exchange capacity, and preventing bacteria growth on its surface. Attached Figure Description

[0045] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0046] The structures, proportions, sizes, etc. illustrated in this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed herein, and are not intended to limit the conditions under which the present invention can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and objectives that the present invention can produce, should still fall within the scope of the technical content disclosed in the present invention.

[0047] Figure 1 This is a schematic diagram of the structure of an air conditioner embodiment provided by the present invention;

[0048] Figure 2 This is a schematic diagram of the structure of an air conditioner indoor unit embodiment provided by the present invention;

[0049] Figure 3 A schematic flowchart of Embodiment 1 of the cleaning requirement detection method for air conditioner indoor heat exchangers provided by the present invention;

[0050] Figure 4 This is a schematic flowchart of Example 4 of the method for detecting the cleaning requirements of an indoor heat exchanger for an air conditioner provided by the present invention. Detailed Implementation

[0051] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0052] The terminology used in the embodiments of this invention is for the purpose of describing particular embodiments only and is not intended to limit the invention. The singular forms “a,” “the,” and “the” used in the embodiments of this invention and the appended claims are also intended to include the plural forms, unless the context clearly indicates otherwise. “Multiple” generally includes at least two, but does not exclude the inclusion of at least one.

[0053] It should be understood that the term "and / or" used in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0054] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a product or system comprising a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a product or system. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the product or system that includes said element.

[0055] Among existing air conditioners with self-cleaning functions, some require users to manually determine the dirt level of the indoor heat exchanger and then manually operate it to activate the self-cleaning function, resulting in untimely cleaning of the indoor heat exchanger and poor heat exchange efficiency; others use the air conditioner's intelligent system to determine the dirt level of the indoor heat exchanger and then activate the self-cleaning function, but this requires reasonable sensor placement, which increases costs.

[0056] This invention creatively provides a method for detecting the cleaning needs of an indoor heat exchanger in an air conditioner. The shell wall of the indoor casing has an indoor air inlet and an indoor air outlet, and the interior of the indoor casing has an indoor air duct connecting the indoor air inlet and the indoor air outlet. An indoor heat exchanger is installed in the indoor air duct. The cleaning needs detection method includes: controlling the air conditioner to a cleaning needs detection state, acquiring the inlet air temperature of the indoor air inlet and the outlet air temperature of the indoor air outlet, calculating the inlet and outlet air temperature difference, and determining whether the indoor heat exchanger needs to be cleaned based on the inlet and outlet air temperature difference.

[0057] It can intelligently and accurately determine whether the indoor heat exchanger needs cleaning, and then clean the indoor heat exchanger in a timely manner to ensure its cleanliness and improve its heat exchange capacity.

[0058] Example 1

[0059] like Figures 1 to 3As shown, this embodiment proposes a method for detecting the cleaning requirements of an air conditioner indoor heat exchanger. The air conditioner includes an indoor unit and an outdoor unit. The indoor unit includes an indoor casing, an indoor fan (hereinafter referred to as the indoor fan), and an indoor heat exchanger. The outdoor unit includes an outdoor casing, an outdoor fan (hereinafter referred to as the outdoor fan), a throttling device (hereinafter referred to as EEV1), and an outdoor heat exchanger. The compressor, four-way valve, indoor heat exchanger, throttling device, and outdoor heat exchanger are connected sequentially through refrigerant pipelines. The shell wall of the indoor casing includes a top wall and a bottom wall. The top wall of the indoor casing forms an indoor air inlet, and the bottom wall of the indoor casing forms an indoor air outlet. An indoor air duct is formed between the indoor air inlet and the indoor air outlet of the indoor casing. Both the air conditioner and the indoor fan are installed in the indoor air duct, with the indoor heat exchanger located upstream of the indoor fan. Under the action of the indoor fan, indoor air enters the indoor air duct through the indoor air inlet, exchanges heat with the indoor heat exchanger as it flows through it, and is then discharged into the room through the indoor air outlet. An outdoor air inlet is formed on the left or right side wall of the outdoor shell, and an outdoor air outlet is formed on the front side wall of the outdoor shell. An outdoor air duct is formed between the outdoor air inlet and the outdoor air outlet, with the outdoor heat exchanger located upstream of the outdoor fan. Under the action of the outdoor fan, outdoor air enters the outdoor air duct through the outdoor air inlet, exchanges heat with the outdoor heat exchanger as it flows through it, and is then discharged into the outside through the outdoor air outlet.

[0060] Air conditioner operating modes include cooling mode and heating mode. When the air conditioner is operating in cooling mode, the refrigerant flow path is: compressor - four-way valve first valve line - outdoor heat exchanger (condenser) - throttling device - indoor heat exchanger (evaporator) - four-way valve second valve line - compressor.

[0061] When the air conditioner is in heating mode, the refrigerant flow path is: compressor - four-way valve third valve - indoor heat exchanger - throttling device - outdoor heat exchanger - four-way valve fourth valve - compressor; when the refrigerant flows through the outdoor heat exchanger, it exchanges heat with the air flowing through the outdoor heat exchanger, and when the refrigerant flows through the indoor heat exchanger, it exchanges heat with the air flowing through the indoor heat exchanger.

[0062] Cleaning needs testing methods include:

[0063] S1. Control the air conditioner to be in a state of detection for cleaning needs;

[0064] S2. Obtain the air inlet temperature and the air outlet temperature of the indoor air inlet;

[0065] S3. Calculate the temperature difference between the inlet and outlet air temperatures;

[0066] S4. Determine whether the indoor heat exchanger needs cleaning based on the temperature difference between the inlet and outlet air, ΔT.

[0067] When the air conditioner is in cooling mode, the temperature difference between the inlet and outlet air is equal to the inlet air temperature minus the outlet air temperature; when the air conditioner is in heating mode, the temperature difference between the inlet and outlet air is equal to the outlet air temperature minus the inlet air temperature; determining whether the indoor heat exchanger needs cleaning involves determining the amount of dust on the surface of the indoor heat exchanger.

[0068] When the air conditioner is in the cleaning demand detection state, it operates according to parameters related to the operating mode. Specifically, in cooling mode, the compressor is controlled to operate at a preset frequency, the four-way valve is de-energized, the indoor fan operates at a preset indoor fan speed, the throttling device is at a preset opening, and the outdoor fan operates at a preset outdoor fan speed. In heating mode, the compressor is controlled to operate at a preset frequency, the four-way valve is energized, the indoor fan operates at a preset indoor fan speed, the throttling device is at a preset opening, and the outdoor fan operates at a preset outdoor fan speed. The throttling device is an electronic expansion valve. The preset frequency is f, the preset indoor fan speed is v1, the preset outdoor fan speed is v2, and the preset opening is p, satisfying: 40Hz≤f≤60Hz, 900rpm≤v1≤1100rpm, 400rpm≤v2≤600rpm, and 200step≤p≤300step.

[0069] In summary, this system controls the air conditioner to detect cleaning needs, determining whether the indoor heat exchanger requires cleaning based on the temperature difference ΔT between the inlet and outlet air. It can intelligently and accurately determine whether the indoor heat exchanger needs cleaning, allowing for timely cleaning to ensure its cleanliness and improve its heat exchange capacity. It requires no sensors, has a simple structure, and does not increase costs. It solves the problems of existing technologies where users manually determine the dirt level of the indoor heat exchanger, leading to delayed cleaning and poor heat exchange performance, and where intelligent air conditioner detection requires additional sensors, resulting in complex structures and high costs.

[0070] Example 2

[0071] Based on Example 1, in this example, the air conditioner is controlled to perform cleaning demand detection based on the time elapsed since the last cleaning of the indoor heat exchanger and whether the air conditioner is currently running, rather than performing cleaning demand detection in real time. This improves the control accuracy of the air conditioner's cleaning demand detection, allowing for accurate and timely determination of whether cleaning demand detection is necessary and avoiding energy waste. Specifically,

[0072] S1 was preceded by:

[0073] S01. Determine whether the time since the last cleaning of the indoor heat exchanger of the air conditioner is greater than the second preset time.

[0074] S02. When the time since the last cleaning of the indoor heat exchanger is less than or equal to the second preset time, the air conditioner is controlled not to perform the cleaning requirement detection.

[0075] S03. When the time since the last cleaning of the indoor heat exchanger exceeds the second preset time, determine whether the air conditioner is running.

[0076] S04. Based on the judgment result of whether the air conditioner is running, control the air conditioner to perform or not perform cleaning requirement detection.

[0077] Furthermore, S04 includes:

[0078] S041. When the air conditioner is running, after the current operation of the air conditioner ends, control the air conditioner to perform a cleaning demand detection.

[0079] S042. When the air conditioner is not running, control the air conditioner to perform a cleaning requirement detection;

[0080] The second preset duration is t2, which satisfies: 160 days ≤ t2 ≤ 200 days;

[0081] Preferably, t2 = 180 days.

[0082] In addition, S1 includes:

[0083] S11. Determine the mode of the air conditioner during its last operation;

[0084] S12. Determine the operating parameters based on the previous operating mode;

[0085] S13. Control the air conditioner to return to the previous operating mode and control the air conditioner to operate with the operating parameters;

[0086] Furthermore, S13 includes:

[0087] S131. When the air conditioner was in cooling mode last time, control the air conditioner to be in cooling mode, control the compressor to run at a preset frequency, control the four-way valve to be in a power-off state, control the indoor fan to run at a preset indoor fan speed, control the throttling device to be in a preset opening degree, and control the outdoor fan to run at a preset outdoor fan speed.

[0088] S132. When the air conditioner was in heating mode last time, control the air conditioner to be in heating mode, control the compressor to run at a preset frequency, control the four-way valve to be in the energized state, control the indoor fan to run at a preset indoor fan speed, control the throttling device to be in a preset opening degree, and control the outdoor fan to run at a preset outdoor fan speed.

[0089] Among them, the preset frequency is f, the preset indoor fan speed is v1, the preset outdoor fan speed is v2, the preset opening degree is p, and f, v1, v2 and p satisfy: 40Hz≤f≤60Hz, 900rpm≤v1≤1100rpm, 400rpm≤v2≤600rpm, 200step≤p≤300step.

[0090] Preferably, f = 50Hz, v1 = 1000rpm, v2 = 500rpm, p = 250step;

[0091] It should be noted that in S2, when the air conditioner is in the cleaning demand detection state and continues for a first preset time, the air inlet temperature and the air outlet temperature are obtained; wherein, the first preset time is t1, and t1 satisfies: 3min≤t1≤7min, preferably, t1=5min.

[0092] S4 includes:

[0093] S41. Calculate the difference between the inlet and outlet air temperature difference ΔT and the preset temperature difference ΔT0;

[0094] S42. Determine whether the indoor heat exchanger needs cleaning based on the difference between the inlet and outlet air temperature difference ΔT and the preset temperature difference ΔT0.

[0095] The preset temperature difference ΔT0 is determined based on the air conditioner's operating mode, the indoor ambient temperature before the air conditioner enters the detection state, and the outdoor ambient temperature.

[0096] The air conditioner is kept in a state of cleanliness detection. When there is no dust accumulation on the surface of the indoor heat exchanger, the heat exchange effect of the indoor heat exchanger is good and the temperature difference between the inlet and outlet air is large. When there is a lot of dust accumulation on the surface of the indoor heat exchanger, the heat exchange effect of the indoor heat exchanger is poor and the temperature difference between the inlet and outlet air is small.

[0097] Specifically, S42 includes:

[0098] S421. When the value of the preset temperature difference minus the inlet and outlet air temperature difference is greater than the preset temperature, it is determined that the indoor heat exchanger needs to be cleaned.

[0099] S422. When the value of the preset temperature difference minus the inlet and outlet air temperature difference is less than or equal to the preset temperature, it is determined that the indoor heat exchanger does not need to be cleaned.

[0100] The preset temperature is T, which satisfies the following conditions: 2℃≤T≤5℃, preferably 3℃≤T≤4℃.

[0101] The air conditioner's operating mode, the relationship between the indoor ambient temperature and the preset indoor ambient temperature, the relationship between the outdoor ambient temperature and the preset outdoor ambient temperature, and the preset temperature difference all have preset corresponding relationships; the methods for determining the preset temperature difference include:

[0102] Before controlling the air conditioner to enter the detection state of cleaning needs, obtain the indoor and outdoor ambient temperatures;

[0103] Compare the indoor ambient temperature with the preset indoor ambient temperature and the outdoor ambient temperature with the preset outdoor ambient temperature;

[0104] Determine the relationship between the indoor ambient temperature and the preset indoor ambient temperature, and the relationship between the outdoor ambient temperature and the preset outdoor ambient temperature;

[0105] The preset temperature difference is determined based on the air conditioner's operating mode, the relationship between the indoor ambient temperature and the preset indoor ambient temperature, the relationship between the outdoor ambient temperature and the preset outdoor ambient temperature, and the preset correspondence.

[0106] The relationship between indoor ambient temperature and preset indoor ambient temperature includes a first relationship and a second relationship. The first relationship is that the indoor ambient temperature is less than the preset indoor ambient temperature, and the second relationship is that the indoor ambient temperature is greater than or equal to the preset indoor ambient temperature. The relationship between outdoor ambient temperature and preset outdoor ambient temperature includes a third relationship and a fourth relationship. The third relationship is that the outdoor ambient temperature is less than the preset outdoor ambient temperature, and the fourth relationship is that the outdoor ambient temperature is greater than or equal to the preset outdoor ambient temperature.

[0107] Specifically, the preset correspondences are shown in Tables 1 and 2. Table 1 shows the preset correspondences between the indoor ambient temperature and the preset indoor ambient temperature, the outdoor ambient temperature and the preset outdoor ambient temperature, and the preset temperature difference when the air conditioner is in cooling mode. Table 2 shows the preset correspondences between the indoor ambient temperature and the preset indoor ambient temperature, the outdoor ambient temperature and the preset outdoor ambient temperature, and the preset temperature difference when the air conditioner is in heating mode. In Tables 1 and 2, T... 外环 The outdoor ambient temperature, T 预设外环 To preset the outdoor ambient temperature, T 内环 Indoor ambient temperature, T 预设内环 Preset indoor ambient temperature;

[0108] When the air conditioner is in cooling mode, T 内环 <T 预设内环 And T 外环 <T 预设外环时 The preset temperature difference ΔT0 is a00; T 内环 <T 预设内环 And T 外环 ≥T 预设外环时 The preset temperature difference ΔT0 is a01; T 内环 ≥T预设内环 And T 外环 <T 预设外环时 The preset temperature difference ΔT0 is a10; T 内环 ≥T 预设内环 And T 外环 ≥T 预设外环时 Then the preset temperature difference ΔT0 is a11; where a00>a01, a10>a11, a10>a00;

[0109] When the air conditioner is in heating mode, T 内环 <T 预设内环 And T 外环 <T 预设外环时 The preset temperature difference ΔT0 is b00; T 内环 <T 预设内环 And T 外环 ≥T 预设外环时 The preset temperature difference ΔT0 is b01; T 内环 ≥T 预设内环 And T 外环 <T 预设外环时 The preset temperature difference ΔT0 is b10; T 内环 ≥T 预设内环 And T 外环 ≥T 预设外环时 The preset temperature difference ΔT0 is then b11; where b00 <b01,b10<b11,b10<b00;

[0110] Table 1. Determination of preset temperature difference ΔT0 in cooling mode.

[0111]

[0112] Table 2. Determination of preset temperature difference ΔT0 in heating mode.

[0113]

[0114] In addition, cleaning needs detection methods also include:

[0115] When it is determined that the indoor heat exchanger needs cleaning, control the air conditioner to execute the cleaning procedure for the indoor heat exchanger.

[0116] After the program to clean the indoor heat exchanger finishes running, the time elapsed since the last cleaning of the indoor heat exchanger is initialized to zero and the timer is restarted.

[0117] When it is determined that the indoor heat exchanger does not require cleaning, a new second preset duration is set as t' = k * t2, where k is a coefficient satisfying: 0.4 ≤ k ≤ 0.6; preferably, k = 0.5.

[0118] Where t2 is the second preset duration;

[0119] The first step is to determine if the time elapsed since the last cleaning of the indoor heat exchanger is greater than the second preset time. Then, after completing the cleaning requirement detection, the next step is to determine if the time elapsed since the last cleaning of the indoor heat exchanger is greater than the second preset time. If a cleaning requirement detection is performed every second preset time, and the result indicates that the indoor heat exchanger does not require cleaning, considering that the interval between the next cleaning requirement detection may be too long, potentially leading to severe surface dirt, a new second preset time is determined to be t' = k*t2.

[0120] The process of cleaning the indoor heat exchanger mainly includes three stages: condensation, frosting, and defrosting of the outdoor unit.

[0121] In summary, this system controls the air conditioner to detect cleaning needs, determining whether the indoor heat exchanger requires cleaning based on the temperature difference ΔT between the inlet and outlet air. It can intelligently and accurately determine whether the indoor heat exchanger needs cleaning, allowing for timely cleaning to ensure its cleanliness and improve its heat exchange capacity. It requires no sensors, has a simple structure, and does not increase costs. It solves the problems of existing technologies where users manually determine the dirt level of the indoor heat exchanger, leading to delayed cleaning and poor heat exchange performance, and where intelligent air conditioner detection requires additional sensors, resulting in complex structures and high costs.

[0122] Example 3

[0123] This embodiment provides an air conditioner, including an indoor shell, an indoor fan, an outdoor fan, and a compressor, a four-way valve, an indoor heat exchanger, a throttling device, and an outdoor heat exchanger connected in sequence through refrigerant pipelines; the shell wall of the indoor shell has an indoor air inlet and an indoor air outlet, and the interior of the indoor shell has an indoor air duct connecting the indoor air inlet and the indoor air outlet, and the indoor fan and the indoor heat exchanger are installed in the indoor air duct.

[0124] The air conditioner uses the cleaning requirement detection method for the indoor heat exchanger described in either Example 1 or 2 to determine whether the indoor heat exchanger needs cleaning.

[0125] Example 4

[0126] like Figure 4 As shown in the figure, this embodiment provides a method for detecting the cleaning needs of an air conditioner indoor heat exchanger. Specifically, it is determined whether the time since the last cleaning of the indoor heat exchanger (hereinafter referred to as the cleaning interval) is greater than 180 days. If it is less than 180 days, the process is to wait and not perform the cleaning needs detection of the indoor heat exchanger. If it is greater than 180 days, it is determined whether the air conditioner is currently running. If the air conditioner is currently running, the cleaning needs detection of the indoor heat exchanger is to be performed after the current operation of the air conditioner is completed. If the air conditioner is not running, the cleaning needs detection of the indoor heat exchanger is performed.

[0127] After starting the cleaning requirement detection of the indoor heat exchanger, the air conditioner is controlled to be in the cleaning requirement detection state. After the air conditioner is in the cleaning requirement detection state, the inlet air temperature of the indoor air inlet and the outlet air temperature of the indoor air outlet can be detected, and then the inlet and outlet air temperature difference ΔT can be calculated.

[0128] When testing the cleaning requirements of the indoor heat exchanger, the air conditioner should operate under the following conditions: Using the air conditioner's previous operating mode as a reference, when the air conditioner was in cooling mode, the four-way valve was de-energized, the compressor operated at frequency f (e.g., 50 Hz), the outdoor fan operated at speed v2 (e.g., 500 rpm), the electronic expansion valve opening was adjusted to p (e.g., 250 steps), and the indoor unit operated at speed v1 (e.g., 1000 rpm). After operating continuously in this state for a period of time (e.g., 5 minutes), the inlet air temperature and outlet air temperature were recorded, and the inlet and outlet air temperature difference ΔT was calculated. In cooling mode, the inlet and outlet air temperature difference ΔT = inlet air temperature - outlet air temperature.

[0129] When the air conditioner was in heating mode, the four-way valve was powered on, the compressor ran at frequency f (e.g., 50 Hz), the indoor unit ran at speed v1 (e.g., 1000 rpm), the electronic expansion valve was set to p (e.g., 250 steps), and the outdoor fan ran at speed v2 (e.g., 500 rpm). After running in this state for a period of time (e.g., 5 minutes), the inlet air temperature and outlet air temperature were recorded, and the inlet and outlet air temperature difference ΔT was calculated. In heating mode, the inlet and outlet air temperature difference ΔT = outlet air temperature - inlet air temperature.

[0130] Before entering the detection state of cleaning needs, record the indoor and outdoor ambient temperatures. Combined with Table 1 and Table 2, the preset temperature difference ΔT0 between cooling mode and heating mode can be obtained.

[0131] After obtaining the inlet and outlet air temperature difference ΔT and the preset temperature difference ΔT0, a judgment is made. If the preset temperature difference ΔT0 - the inlet and outlet air temperature difference ΔT is greater than the preset temperature T, it is determined that the indoor heat exchanger needs to be cleaned, and the self-cleaning mode for cleaning the indoor heat exchanger needs to be run. After the self-cleaning mode is completed, the time elapsed since the last cleaning of the indoor heat exchanger is initialized to zero. The timer is restarted and the cycle continues. The preset temperature is T, and T satisfies: 3℃≤T≤4℃.

[0132] If the preset temperature difference ΔT0 - the inlet and outlet air temperature difference ΔT is less than or equal to the preset temperature T, then the new second preset duration is set to 90 days; the timing continues and the cycle continues.

[0133] It should be noted that when testing the cleaning requirements of the indoor heat exchanger, the preset frequency of the compressor, the preset state of the four-way valve, the preset indoor fan speed, the preset opening degree of the throttling device, and the preset outdoor fan speed are all fixed values; however, when the air conditioner is running in cooling or heating mode, the compressor frequency, the state of the four-way valve, the speed of the indoor fan, the opening degree of the throttling device, and the speed of the outdoor fan are not fixed values.

[0134] Exemplary embodiments of this disclosure have been specifically shown and described above. It should be understood that this disclosure is not limited to the detailed structures, arrangements, or implementations described herein; rather, this disclosure is intended to cover various modifications and equivalent arrangements contained within the spirit and scope of the appended claims.

Claims

1. A method for detecting the cleaning requirements of an indoor heat exchanger in an air conditioner, the air conditioner comprising an indoor casing, the casing wall of which forms an indoor air inlet and an indoor air outlet, the interior of which forms an indoor air duct connecting the indoor air inlet and the indoor air outlet, the indoor heat exchanger being disposed within the indoor air duct; characterized in that, The cleaning requirement detection method includes: The air conditioner is controlled to be in a state of cleaning requirement detection; Obtain the air inlet temperature of the indoor air inlet and the air outlet temperature of the indoor air outlet; Calculate the temperature difference between the inlet and outlet air temperatures; Based on the temperature difference between the inlet and outlet air, determine whether the indoor heat exchanger needs cleaning; Before the air conditioner is put into a cleaning demand detection state, the following steps are also included: Determine whether the time since the last cleaning of the indoor heat exchanger of the air conditioner is greater than a second preset time. When the time since the last cleaning of the indoor heat exchanger by the air conditioner is less than or equal to the second preset time, the air conditioner is controlled not to perform the cleaning requirement detection. If the time since the last cleaning of the indoor heat exchanger is longer than the second preset time, it is determined whether the air conditioner is currently running. Based on the determination result of whether the air conditioner is running, control the air conditioner to perform or not perform cleaning requirement detection; The cleaning requirement detection method further includes: When it is determined that the indoor heat exchanger needs to be cleaned, after the cleaning of the indoor heat exchanger is completed, the time elapsed since the last cleaning of the indoor heat exchanger is initialized to zero and the timer is restarted. When it is determined that the indoor heat exchanger does not need to be cleaned, a new second preset duration is determined as t'=k*t2, where k is a coefficient satisfying: 0.4≤k≤0.6; and t2 is the second preset duration. The air conditioner's operating mode includes at least one of a cooling mode and a heating mode; when the air conditioner is in a cleaning demand detection state, the air conditioner operates according to parameters related to the operating mode; when the air conditioner is in the cooling mode, the inlet and outlet air temperature difference is equal to the inlet air temperature minus the outlet air temperature; when the air conditioner is in the heating mode, the inlet and outlet air temperature difference is equal to the outlet air temperature minus the inlet air temperature.

2. The method for detecting the cleaning requirements of an air conditioner indoor heat exchanger according to claim 1, characterized in that, The step of determining whether the indoor heat exchanger needs cleaning based on the inlet and outlet air temperature difference includes: Calculate the difference between the inlet and outlet air temperature difference and the preset temperature difference; Based on the difference between the inlet and outlet air temperature difference and the preset temperature difference, determine whether the indoor heat exchanger needs cleaning; The preset temperature difference is determined based on the air conditioner's operating mode, the indoor ambient temperature before the air conditioner enters the detection state, and the outdoor ambient temperature.

3. The method for detecting the cleaning requirements of an air conditioner indoor heat exchanger according to claim 2, characterized in that, Determining whether the indoor heat exchanger needs cleaning based on the difference between the inlet and outlet air temperature differences and the preset temperature difference includes: When the value of the preset temperature difference minus the inlet and outlet air temperature difference is greater than the preset temperature, it is determined that the indoor heat exchanger needs to be cleaned. When the value of the preset temperature difference minus the inlet and outlet air temperature difference is less than or equal to the preset temperature, it is determined that the indoor heat exchanger does not need to be cleaned.

4. The method for detecting the cleaning requirements of an air conditioner indoor heat exchanger according to claim 1, characterized in that, The control of the air conditioner to be in a cleaning demand detection state includes: Determine the mode in which the air conditioner last operated; Determine the operating parameters based on the previous operating mode; Control the air conditioner to be in the previous operating mode and control the air conditioner to operate with the operating parameters.

5. The method for detecting the cleaning requirements of an air conditioner indoor heat exchanger according to claim 4, characterized in that, The air conditioner includes an indoor fan, an outdoor fan, and a compressor, a four-way valve, an indoor heat exchanger, a throttling device, and an outdoor heat exchanger connected in sequence via refrigerant piping; controlling the air conditioner to be in the previous operating mode and controlling the air conditioner to operate with the operating parameters includes: When the air conditioner was previously in cooling mode, the air conditioner is controlled to be in cooling mode, and the compressor is controlled to run at a preset frequency. The four-way valve is in a power-off state, the indoor fan runs at a preset indoor fan speed, the throttling device is in a preset opening degree, and the outdoor fan runs at a preset outdoor fan speed. When the air conditioner was previously in heating mode, the air conditioner is controlled to be in heating mode, and the compressor is controlled to run at a preset frequency. The four-way valve is powered on, the indoor fan runs at a preset indoor fan speed, the throttling device is at a preset opening, and the outdoor fan runs at a preset outdoor fan speed.

6. The method for detecting the cleaning requirements of an air conditioner indoor heat exchanger according to claim 1, characterized in that, The step of controlling the air conditioner to perform or not perform cleaning requirement detection based on the determination result of whether the air conditioner is running includes: When the air conditioner is running, after the current operation of the air conditioner is completed, control the air conditioner to perform a cleaning demand detection; When the air conditioner is not running, control the air conditioner to perform a cleaning requirement detection.

7. The method for detecting the cleaning requirements of an air conditioner indoor heat exchanger according to claim 2, characterized in that, The air conditioner's operating mode, the relationship between the indoor ambient temperature and the preset indoor ambient temperature, the relationship between the outdoor ambient temperature and the preset outdoor ambient temperature, and the preset temperature difference have a preset correspondence. The method for determining the preset temperature difference includes: Compare the indoor ambient temperature with the preset indoor ambient temperature, and the outdoor ambient temperature with the preset outdoor ambient temperature; Determine the relationship between the indoor ambient temperature and the preset indoor ambient temperature, and the relationship between the outdoor ambient temperature and the preset outdoor ambient temperature; The preset temperature difference is determined based on the air conditioner's operating mode, the relationship between the indoor ambient temperature and the preset indoor ambient temperature, the relationship between the outdoor ambient temperature and the preset outdoor ambient temperature, and the preset correspondence.

8. An air conditioner, characterized in that, It includes an indoor shell, an indoor fan, an outdoor fan, and a compressor, a four-way valve, an indoor heat exchanger, a throttling device, and an outdoor heat exchanger connected in sequence via refrigerant piping; the shell wall of the indoor shell has an indoor air inlet and an indoor air outlet, and the interior of the indoor shell has an indoor air duct connecting the indoor air inlet and the indoor air outlet, and the indoor fan and the indoor heat exchanger are installed in the indoor air duct; The air conditioner uses the cleaning requirement detection method for the indoor heat exchanger as described in any one of claims 1 to 7 to determine whether the indoor heat exchanger needs cleaning.

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