A multi-connected air conditioner

Abstract

The present invention discloses a multi-split air conditioner, comprising an outdoor unit, a plurality of indoor units, a plurality of air pipes, a plurality of liquid pipes, a plurality of first temperature sensors, a plurality of second temperature sensors, and a control unit; the outdoor unit comprises an outdoor heat exchanger; the indoor unit comprises an indoor heat exchanger; each first temperature sensor is respectively arranged on each air pipe for detecting the air pipe temperature; each second temperature sensor is respectively arranged on each liquid pipe for detecting the liquid pipe temperature; the control unit is provided with an air pipe temperature limit, a liquid pipe temperature limit, and a first time limit, and is respectively connected with each first temperature sensor and each second temperature sensor to receive each air pipe temperature and each liquid pipe temperature; and is configured to judge whether the air pipe temperature and the liquid pipe temperature of the indoor unit that is not in operation are respectively within the air pipe temperature limit and the liquid pipe temperature limit and the duration reaches the first time limit; if yes, it is judged that the high temperature sterilization is completed; if no, it is judged that the high temperature sterilization is not completed. The present invention improves the sterilization efficiency and saves energy.

Description

Technical Field

[0001] The invention relates to the technical field of air conditioning, and in particular to a multi-split air conditioner. Background Art

[0002] As users pay more attention to healthy air, the demand for sterilization air conditioners is increasing. The high-temperature sterilization of multi-split air conditioners is to generate high temperature in the indoor heat exchanger when the multi-split air conditioner is operated in a special heating mode, and sterilize the indoor heat exchanger at high temperature. That is, on the one hand, the multi-split air conditioner reduces the condensation effect by controlling the indoor fan at low wind speed; on the other hand, under the premise of ensuring the reliability of the system, the high-pressure value allowed by the system is increased, the compressor is prompted to operate at a high frequency, the exhaust volume is increased, and the exhaust temperature is increased; the indoor heat exchanger quickly reaches the high-temperature sterilization temperature and operates continuously.

[0003] Since the high-temperature sterilization mode is a special heating mode, it is greatly affected by the ambient temperature; that is, the ambient temperature greatly affects the effect of high-temperature sterilization. In order to ensure the effect of high-temperature sterilization, the number of indoor units that participate in high-temperature sterilization is limited; the high-temperature sterilization of the multi-split air conditioner is completed in two or three groups or even more groups. And because high-temperature sterilization requires high temperature and long cycle, and the high temperature needs to be maintained continuously and cannot be interrupted, the sterilization efficiency is low and the unit energy efficiency is poor, which affects the user experience.

[0004] In addition, when some indoor units start the low-wind heating mode for high-temperature sterilization, other indoor units that are not started are in standby mode, and the flow of refrigerant inside them is limited; because the indoor fan is in a stopped state, the indoor heat exchanger may be in a high-temperature state, and if this high temperature can last for a certain period of time, it can also play an effective sterilization role. If the indoor unit that has been sterilized is repeatedly sterilized at high temperature, it will cause energy waste.

[0005] The above information disclosed in the background technology is only used to increase the understanding of the background technology of the present application, and therefore, it may include information that does not constitute the prior art known to ordinary technicians in the field. Summary of the invention

[0006] In response to the problems pointed out in the background technology, the present invention judges the air pipe temperature value and liquid pipe temperature value of the unstarted indoor unit, and judges the duration when the air pipe temperature value and the liquid pipe temperature value reach the specified threshold value, thereby realizing the judgment of the sterilization effect of the unstarted indoor unit, preventing repeated sterilization, improving the sterilization efficiency and saving energy.

[0007] In order to achieve the above-mentioned purpose, the present invention adopts the following technical solutions:

[0008] In the first embodiment of the present application, a multi-link is provided, which includes:

[0009] An outdoor unit, which includes a compressor, a four-way valve, and an outdoor heat exchanger;

[0010] A plurality of indoor units; the indoor units include indoor heat exchangers;

[0011] A plurality of air pipes, one end of which is respectively connected to the same port of the four-way valve, and the other end of which is respectively connected to one end of each of the indoor heat exchangers;

[0012] A plurality of liquid pipes, one end of which is respectively connected to the same port of the outdoor heat exchanger, and the other end of which is respectively connected to the other end of each of the indoor heat exchangers;

[0013] A plurality of first temperature sensors, which are respectively arranged on each of the air pipes and are used to detect the temperature of the air pipe where they are located; the measured temperature of the air pipe is recorded as the air pipe temperature;

[0014] A plurality of second temperature sensors, which are respectively arranged on each of the liquid pipes and are used to detect the temperature of the liquid pipe where they are located; the measured temperature of the liquid pipe is recorded as the liquid pipe temperature;

[0015] A control unit is configured with an air pipe temperature limit, a liquid pipe temperature limit, and a first time limit; the control unit is respectively connected to each of the first temperature sensors and each of the second temperature sensors, receives each of the air pipe temperatures and each of the liquid pipe temperatures, and is configured to determine whether the air pipe temperature and the liquid pipe temperature of the indoor unit that is not in operation are respectively within the air pipe temperature limit and the liquid pipe temperature limit; if so, determine whether the duration of the air pipe temperature and the liquid pipe temperature being respectively within the air pipe temperature limit and the liquid pipe temperature limit reaches the first time limit; if so, determine that the high-temperature sterilization of the indoor unit is completed; if not, determine that the high-temperature sterilization of the indoor unit is not completed.

[0016] In a second embodiment of the present application, a multi-link is provided, which has:

[0017] The control unit is configured with a high-temperature sterilization mode, and when the high-temperature sterilization mode is running, the control unit controls the indoor unit to run a low-wind heating mode, so as to sterilize the indoor heat exchanger at high temperature;

[0018] The control unit is also configured to judge whether the gas pipe temperature and the liquid pipe temperature of each of the indoor units that are not running the low-wind heating mode are within the gas pipe temperature limit and the liquid pipe temperature limit, respectively; if so, then judge whether the duration of the gas pipe temperature and the liquid pipe temperature of each of the indoor units that are not running the low-wind heating mode within the gas pipe temperature limit and the liquid pipe temperature limit, respectively, reaches the first time limit, which is used to judge whether the high-temperature sterilization of each of the indoor units that are not running in the high-temperature sterilization mode has been completed.

[0019] In the third embodiment of the present application, a multi-link is provided, which has:

[0020] The control unit is configured with a second time limit and a low-wind heating mode continuous start-up times limit; the second time limit is not less than the first time limit;

[0021] When the high-temperature sterilization mode is run, the continuous operation time of each indoor unit running the low-wind heating mode is obtained and recorded as the sterilization time;

[0022] comparing the sterilization time with the second time limit; when the sterilization time reaches the second time limit, determining that the high-temperature sterilization of the indoor unit is completed;

[0023] When the sterilization time does not reach the second time limit, recording the number of consecutive starts of the indoor unit in the low-air heating mode, and comparing the number of consecutive starts with the limit of the number of consecutive starts in the low-air heating mode;

[0024] When the number of consecutive starts does not exceed the limit of the number of consecutive starts of the low-wind heating mode, restarting the low-wind heating mode;

[0025] When the number of consecutive starts exceeds the limit of the number of consecutive starts of the low-airflow heating mode, the low-airflow heating mode is stopped and it is determined that the high-temperature sterilization of the indoor unit has failed.

[0026] In a fourth embodiment of the present application, a multi-link is provided, comprising:

[0027] Also includes at least a third temperature sensor and a fourth temperature sensor;

[0028] The third temperature sensor is used to detect the indoor ambient temperature; the fourth temperature sensor is used to detect the outdoor ambient temperature;

[0029] The control unit is connected to the third temperature sensor and the fourth temperature sensor respectively, and receives the indoor ambient temperature and the outdoor ambient temperature detected by them; and is configured to determine the capacity of the indoor unit running the low-wind heating mode and the ratio to the capacity of the outdoor unit according to the indoor ambient temperature and the outdoor temperature when running the high-temperature sterilization mode.

[0030] In a fifth embodiment of the present application, a multi-link is provided, comprising:

[0031] The control unit is configured with a plurality of temperature interval threshold combinations and a plurality of capacity ratio thresholds corresponding to each of the temperature interval threshold combinations; the temperature interval threshold combination is a combination of an indoor environment temperature threshold and an outdoor environment threshold; the control unit is configured with a plurality of the indoor environment temperature thresholds and a plurality of the outdoor environment temperature thresholds; each of the outdoor environment temperature thresholds forms at least one outdoor continuous temperature interval; each of the indoor environment temperature thresholds forms an indoor continuous temperature interval;

[0032] The control unit is configured to determine the capacity ratio threshold according to the received indoor ambient temperature and the outdoor temperature; and is configured to determine the sum of the capacities of the indoor units activated in the high-temperature sterilization mode according to the capacity ratio threshold.

[0033] In the sixth embodiment of the present application, a multi-link is provided, comprising:

[0034] Each of the capacity ratio thresholds includes a basic value and an amplitude value; the basic value is the middle value of the capacity ratio threshold; the amplitude value is the ratio of the smaller capacity of each of the indoor units to the capacity of the outdoor unit, and is used to limit the amplitude on both sides of the basic value;

[0035] Each of the indoor units is respectively configured with a different coding address;

[0036] The control unit collects the coding address and capacity value of each of the indoor units; and is configured to add the indoor units to the startup list of the low-wind heating mode one by one according to the coding address, so that the ratio of the capacity sum of each of the indoor units in the startup list to the capacity of the outdoor unit meets the requirement of the capacity ratio threshold for the capacity sum of each of the indoor units.

[0037] In the seventh embodiment of the present application, a multi-link is provided, comprising:

[0038] When the high temperature sterilization mode is run to determine the startup list:

[0039] If the ratio of the capacity of the first added indoor unit to the capacity of the outdoor unit reaches the upper limit of the capacity ratio threshold, starting the indoor unit in the current start-up list;

[0040] If the ratio of the capacity of each indoor unit in the startup list to the capacity of the outdoor unit does not reach the lower limit of the capacity ratio threshold, determine whether it is the last indoor unit; if yes, start with the current startup list; if not, continue to add the indoor unit;

[0041] If the ratio of the capacity of each indoor unit in the startup list to the capacity of the outdoor unit reaches the upper limit of the capacity ratio threshold, determine whether it is the last indoor unit; if so, start with the current startup list; if not, start with the startup list before adding the indoor unit.

[0042] In an eighth embodiment of the present application, a multi-link is provided, wherein

[0043] Also included is an operation interface, which is included in the control unit or connected to the control unit, including a high-temperature sterilization button and a display, and is used to trigger the high-temperature sterilization mode when the high-temperature sterilization button is operated;

[0044] When the high-temperature sterilization mode is triggered, the display provides exit, immediate execution, and delayed execution options, which are respectively used to exit the high-temperature sterilization mode, enter the high-temperature sterilization mode, and delay entering the high-temperature sterilization mode.

[0045] In the ninth embodiment of the present application, a multi-link is provided, comprising:

[0046] When the delayed execution option is selected, the operation interface provides delay duration setting, confirmation and cancellation options;

[0047] When the delay time setting is operated and confirmed, the control unit controls the execution of the high-temperature sterilization mode countdown; and when the countdown is completed, the high-temperature sterilization mode operation is immediately entered;

[0048] When cancel is selected, the high temperature sterilization mode is exited.

[0049] In the tenth embodiment of the present application, a multi-link is provided, comprising:

[0050] The operation interface also includes a plurality of operation mode setting buttons;

[0051] When any of the operation mode setting buttons is operated during the high-temperature sterilization mode, the high-temperature sterilization mode is exited;

[0052] When the high-temperature sterilization of all the indoor units is completed, the operation interface gives a high-temperature sterilization success prompt; when the high-temperature sterilization of the indoor units fails, the operation interface gives a high-temperature sterilization failure prompt; when any of the operation mode setting buttons is operated, the high-temperature sterilization success or failure prompt is exited.

[0053] Compared with the prior art, the advantages and positive effects of the present invention are:

[0054] In the first embodiment, when the multi-split system is in heating operation, the gas pipe temperature and the liquid pipe temperature at both ends of the indoor heat exchanger of the indoor unit that is not in operation are detected and judged. When the specified conditions are met, it is considered that the sterilization effect is achieved, and the sterilization monitoring is implemented in any operation mode of the indoor unit, thereby preventing repeated sterilization when the high-temperature sterilization mode is running, reducing the number of indoor units that need to start sterilization, and thus improving the sterilization efficiency; in addition, since the number of indoor units that start sterilization is reduced, energy consumption is reduced, saving energy.

[0055] In the second embodiment, the gas pipe temperature and liquid pipe temperature of the unstarted indoor unit are detected and judged only when the high-temperature sterilization mode is triggered, so as to judge the sterilization situation when the sterilization effect is most likely to be achieved when the indoor unit is not started in the high-temperature sterilization mode, thereby improving the control and judgment efficiency.

[0056] In the third embodiment, the high-temperature sterilization effect of the indoor unit activated in the low-air heating mode in the high-temperature sterilization mode is ensured.

[0057] In the fourth embodiment, the capacity of the indoor unit started in the low-wind heating mode under the high-temperature sterilization mode is automatically matched according to the indoor ambient temperature and the outdoor ambient temperature, thereby improving the efficiency and reliability of starting the indoor unit for high-temperature sterilization when the high-temperature sterilization mode is running.

[0058] In the fifth embodiment, the corresponding conditions of the capacity ratio threshold of the multi-split air conditioner are refined to improve the accuracy and reliability of high-temperature sterilization of the multi-split air conditioner started by the capacity ratio threshold.

[0059] In the sixth embodiment, the ratio of the smaller capacity value of each indoor unit in the multi-split air-conditioning system to the capacity of the outdoor unit is used as the amplitude value, so that the capacity ratio threshold has an adjustable threshold related to the capacity of the matching indoor units, thereby increasing the probability that the capacity of each indoor unit in the startup list and the ratio to the outdoor unit capacity are within the capacity ratio threshold range, thereby improving the reliability and efficiency of control.

[0060] In the seventh embodiment, the startup control process of the indoor units at both ends of the list of added indoor unit code addresses in the high-temperature sterilization mode is set in detail to improve the control efficiency and reliability.

[0061] In the eighth embodiment, when the high-temperature sterilization mode is triggered, a variety of options are provided through the operation interface to provide clear exit, execution and delayed execution instructions, expand user choices, meet user's diverse needs, and enhance user experience.

[0062] In the ninth embodiment, by setting the delayed execution option, the delay duration can be set independently to improve the user experience.

[0063] In the tenth embodiment, the use mode of the multi-split air conditioner is set to a high priority mode to prevent the multi-split air conditioner from being unavailable, thereby improving the user experience.

[0064] After reading the specific embodiments of the present invention in conjunction with the accompanying drawings, other features and advantages of the present invention will become more clear. BRIEF DESCRIPTION OF THE DRAWINGS

[0065] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0066] Figure 1 A schematic diagram of system composition and connection according to an embodiment of a multi-split air conditioner;

[0067] Figure 2 is a schematic diagram of electrical control connection according to an embodiment of a multi-split air conditioner;

[0068] Figure 3 A schematic diagram of a high-temperature sterilization mode triggering control flow according to an embodiment of a multi-split air conditioner;

[0069] Figure 4 A schematic diagram of a control flow for determining a startup list in a high-temperature sterilization mode according to an embodiment of a multi-split air conditioner;

[0070] Figure 5 A schematic diagram of a control flow for determining a startup list in a high-temperature sterilization mode according to an embodiment of a multi-split air conditioner;

[0071] Figure 6 A schematic diagram of a control flow for determining a startup list in a high-temperature sterilization mode according to an embodiment of a multi-split air conditioner;

[0072] Figure 7 A schematic diagram of a flow chart of determining whether high-temperature sterilization is completed according to an embodiment of a multi-split air conditioner;

[0073] Figure 8 A schematic diagram of a flow chart of determining whether high-temperature sterilization of an indoor unit is completed when high-temperature sterilization mode is not started according to an embodiment of a multi-split air conditioner;

[0074] Fig. 9 A schematic diagram of a flow chart of determining whether high-temperature sterilization of an indoor unit is completed in a high-temperature sterilization mode according to an embodiment of a multi-split air conditioner;

[0075] Fig.10 A schematic diagram of a process flow when high-temperature sterilization fails according to an embodiment of a multi-split air conditioner;

[0076] Fig.11 The figure is an example of a corresponding list of temperature interval threshold combinations and capacity ratio thresholds according to an embodiment of a multi-split air conditioner.

[0077] Reference numerals:

[0078] 1. Outdoor unit; 11. Compressor; 12. Four-way valve; 13. Outdoor heat exchanger; 14. Fourth temperature sensor; 15. Outdoor electronic expansion valve; 2. Indoor unit; 21. Indoor heat exchanger; 22. Gas pipe; 23. Liquid pipe; 24. First temperature sensor; 25. Second temperature sensor; 26. Indoor electronic expansion valve; 27. Fifth temperature sensor; 3. Control unit; 31. Operation interface; 32. Indoor control device; 33. Outdoor control device; 311. Third temperature sensor;

[0079] Ti, indoor ambient temperature; To, outdoor ambient temperature; Tq, gas pipe temperature; Ty, liquid pipe temperature; k, amplitude value. DETAILED DESCRIPTION

[0080] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0081] In the description of the present application, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the feature. In the description of the present application, unless otherwise specified, "plurality" means two or more.

[0082] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0083] The disclosure below provides many different embodiments or examples to implement different structures or controls of the present invention. In order to simplify the disclosure of the present invention, the components and settings of specific examples are described below. Of course, they are only examples, and the purpose is not to limit the present invention. In addition, the present invention can repeat reference numbers and / or reference letters in different examples, and this repetition is for the purpose of simplification and clarity, which itself does not indicate the relationship between the various embodiments and / or settings discussed.

[0084] Reference Figure 1 In the present application, the multi-split air conditioner includes an outdoor unit 1 and a plurality of indoor units 2; a refrigeration cycle of the air conditioner is performed by using a compressor 11, a condenser, an expansion valve and an evaporator. The refrigeration cycle includes a series of processes involving compression, condensation, expansion and evaporation to cool or heat the indoor space.

[0085] The low-temperature and low-pressure refrigerant enters the compressor 11, which compresses it into a high-temperature and high-pressure refrigerant gas and discharges the compressed refrigerant gas. The discharged refrigerant gas flows into the condenser. The condenser condenses the compressed refrigerant into a liquid phase, and heat is released to the surrounding environment through the condensation process.

[0086] The expansion valve expands the high-temperature and high-pressure liquid refrigerant condensed in the condenser into a low-pressure liquid refrigerant. The evaporator evaporates the refrigerant expanded in the expansion valve and returns the refrigerant gas in a low-temperature and low-pressure state to the compressor 11. The evaporator can achieve a cooling effect by utilizing the latent heat of evaporation of the refrigerant to exchange heat with the material to be cooled. The condenser can achieve a heating effect by utilizing the heat released by condensation of the refrigerant to exchange heat with the material to be cooled. In the entire cycle, the air conditioner can adjust the temperature of the indoor space by absorbing heat in the evaporator or releasing heat in the condenser.

[0087] The outdoor unit 1 of the multi-split air conditioner refers to the part of the refrigeration cycle including the compressor 11 and the outdoor heat exchanger 13, the indoor unit 2 includes the indoor heat exchanger 21, and the expansion valve can be provided in the indoor unit 2 or the outdoor unit 1, or the outdoor unit 1 and each indoor unit 2 are respectively provided with an outdoor electronic expansion valve 15 and an indoor electronic expansion valve 26.

[0088] The indoor heat exchanger 21 and the outdoor heat exchanger 13 function as a condenser or an evaporator. When the indoor heat exchanger 21 functions as a condenser, the multi-split air conditioner functions as a heater in a heating mode, and when the indoor heat exchanger 21 functions as an evaporator, the multi-split air conditioner functions as a cooler in a cooling mode.

[0089] The outdoor unit 1 of the multi-split air conditioner also includes a four-way valve 12, which is respectively connected to the exhaust port and the intake port of the indoor heat exchanger 21, the outdoor heat exchanger 13, and the compressor 11, and is used to change the flow direction of the refrigerant in the multi-split air conditioning system to realize the conversion of the indoor heat exchanger 21 and the outdoor heat exchanger 13 between the evaporator and the condenser, thereby realizing the conversion between the heater mode and the cooler mode.

[0090] The multi-connected air conditioner of the present invention further includes a plurality of air pipes 22, one end of which is respectively connected to the same port of the four-way valve 12, and the other end is respectively connected to one end of each indoor heat exchanger 21. Of course, one end of each air pipe 22 can be respectively connected through a branch air pipe 22 connected to one port of the four-way valve 12, so that the gas refrigerant discharged from the exhaust port of the compressor 11 enters each indoor heat exchanger 21 through the four-way valve 12 and each air pipe 22 in the heating mode.

[0091] The multi-split air conditioner of the present invention further includes a plurality of liquid pipes 23, one end of which is respectively connected to the same port of the outdoor heat exchanger 13, and the other end is respectively connected to the other end of each indoor heat exchanger 21. Of course, one end of each liquid pipe 23 can be connected to the outdoor heat exchanger 13 through a liquid distribution pipe 23 connected to the same port of the outdoor heat exchanger 13; when the heating mode is realized, the liquid refrigerant flowing out of the indoor heat exchanger 21 enters the outdoor heat exchanger 13 through each liquid pipe 23.

[0092] The multi-split air conditioner of the present invention further includes a plurality of first temperature sensors 24, which are respectively disposed on each air pipe 22 and are used to detect the temperature of the air pipe 22, and the detected temperature of the air pipe 22 is recorded as the air pipe temperature Tq.

[0093] The multi-split air conditioner of the present invention further includes a plurality of second temperature sensors 25, which are respectively disposed on each liquid pipe 23 and are used to detect the temperature of the liquid pipe 23, and the detected temperature of the liquid pipe 23 is recorded as the liquid pipe temperature Ty.

[0094] The multi-split air conditioner of the present invention also includes a control unit 3, which is equipped with an air pipe temperature limit, a liquid pipe temperature limit, and a first time limit; the control unit 3 is connected to each first temperature sensor 24 and each second temperature sensor 25, respectively, and receives each air pipe temperature Tq and each liquid pipe temperature Ty measured by each first temperature sensor 24 and each second temperature sensor 25; and is configured to determine whether the air pipe temperature Tq and the liquid pipe temperature Ty of the indoor unit 2 that is not in operation are respectively within the range of the air pipe temperature limit and the liquid pipe temperature limit; if so, perform step S232 to determine whether the air pipe temperature Tq and the liquid pipe temperature Ty continue to reach the first time limit within the range of the air pipe temperature limit and the liquid pipe temperature limit; and if so, confirm that the high-temperature sterilization of the corresponding indoor unit 2 is completed, and execute step S25; if not, confirm that the high-temperature sterilization of the corresponding indoor unit 2 is not completed, and execute step 233 to continue to obtain the air pipe temperature Tq and the liquid pipe temperature Ty of the indoor unit 2 that is not started.

[0095] Step S25 specifically includes, when it is determined that the corresponding indoor unit 2 has completed high temperature sterilization, marking it as completed, and when the multi-split air conditioner is operating in the high temperature sterilization mode, the indoor unit 2 marked as completed is not started.

[0096] When the multi-split air conditioner of the present invention is in heating operation, the gas pipe temperature Tq and the liquid pipe temperature Ty at both ends of the indoor heat exchanger 21 of the non-operating indoor unit 2 are detected and judged; when the specified conditions are met, it is considered that the sterilization effect is achieved, and the sterilization monitoring of the indoor unit 2 in the non-operating mode is realized, thereby preventing the indoor unit 2 that has completed high-temperature sterilization from being repeatedly sterilized when the high-temperature sterilization mode is running, thereby reducing the number of indoor units 2 that need to be started and operated for sterilization as much as possible, thereby improving the sterilization efficiency; in addition, since the number of indoor units 2 that need to be started and operated for sterilization is reduced, the energy consumption during non-heating operation and non-cooling operation is reduced, saving energy.

[0097] The control and principle of the high-temperature sterilization mode of the multi-split air conditioner of the present invention are described in detail below through specific embodiments.

[0098] In some embodiments of the present invention, reference Figure 1 , Figure 2 , Figure 7 , Figure 8 , Fig. 9 The control unit 3 is equipped with a high-temperature sterilization mode, and is configured so that when the high-temperature sterilization mode is running, the indoor unit 2 of the control part runs the low-wind heating mode, and in the low-wind heating mode, the wind speed of the fan of the indoor unit 2 is adjusted to increase the operating frequency, exhaust volume and exhaust temperature of the compressor 11 as much as possible, so as to achieve high-temperature sterilization by maintaining a high temperature for the indoor heat exchanger 21 of the started indoor unit 2 when the multi-split system is working normally.

[0099] When the high-temperature sterilization mode is in operation, some of the indoor units 2 operate in the low-wind heating mode, and the other indoor units 2 are in the standby state. At this time, the indoor electronic expansion valve 26 of the indoor unit 2 in the standby state is in a fixed opening state, so that a set amount of refrigerant can circulate in the indoor heat exchanger 21 of the indoor unit 2 in the standby state, ensuring the pressure balance of the refrigerant in the multi-split air conditioning system.

[0100] When the high temperature sterilization mode is in operation, the control unit 3 starts the first timer and receives the gas pipe temperature Tq and the liquid pipe temperature Ty of the corresponding indoor unit 2 detected by the first temperature sensor 24 and the second temperature sensor 25 of each indoor unit 2 that is not in operation (standby).

[0101] The control unit 3 compares the received gas pipe temperature Tq and liquid pipe temperature Ty with the gas pipe temperature limit and liquid pipe temperature limit configured by the control unit 3, respectively. If the gas pipe temperature Tq and the liquid pipe temperature Ty are respectively within the threshold range of the gas pipe temperature limit and the liquid pipe temperature limit configured by the control unit 3, step S232 is executed to determine whether the timing duration of the first timer reaches the first time limit; that is, the duration of the gas pipe temperature Tq and the liquid pipe temperature Ty within the threshold range of the gas pipe temperature limit and the liquid pipe temperature limit configured by the control unit 3 is determined; and if the timing duration of the first timer reaches the first time limit, it is determined that the high-temperature sterilization of the corresponding indoor unit 2 that is not in operation (standby) is completed, and step 25 is executed to mark the indoor unit 2 that has completed the high-temperature sterilization as completed with the high-temperature sterilization; if the timing duration of the first timer does not reach the first time limit, step S233 is executed to perform the next round of gas pipe temperature Tq and liquid pipe temperature Ty or and continue to determine the acquired gas pipe temperature Tq and liquid pipe temperature Ty.

[0102] When judging whether the gas pipe temperature Tq and the liquid pipe temperature Ty are respectively within the threshold range of the gas pipe temperature limit and the liquid pipe temperature limit and determining that the gas pipe temperature Tq and the liquid pipe temperature Ty are respectively not within the threshold range of the gas pipe temperature limit and the liquid pipe temperature limit, execute step S231 to clear the first timer and restart the timing, then execute step S233 to receive the next round of gas pipe temperature Tq and liquid pipe temperature Ty and continue to judge the acquired gas pipe temperature Tq and liquid pipe temperature Ty.

[0103] When the high-temperature sterilization of the indoor unit 2 that is not in operation (on standby) is completed, step S25 is executed to mark it as completed with high-temperature sterilization, so that the control unit 3 recognizes it as the indoor unit 2 that has completed high-temperature sterilization, and does not start the low-wind heating mode for high-temperature sterilization when running in the high-temperature sterilization mode, thereby improving the sterilization efficiency while reducing energy consumption and saving energy.

[0104] When the gas pipe temperature Tq is not within the gas pipe temperature limit range or the liquid pipe temperature Ty is not within the liquid pipe temperature limit range, or the gas pipe temperature Tq and the liquid pipe temperature Ty are respectively within the gas pipe temperature limit range and the liquid pipe temperature limit range but the duration does not reach the first time limit, it is confirmed that the high-temperature sterilization of the corresponding non-operating (standby) indoor unit 2 is not completed, and the high-temperature sterilization completion mark is not performed for it.

[0105] The multi-split air conditioner of this embodiment only detects and judges the gas pipe temperature Tq and liquid pipe temperature Ty of the unstarted indoor unit 2 when the high-temperature sterilization mode is triggered, so as to judge the sterilization status of the unstarted indoor unit 2 in the high-temperature sterilization mode and improve the control and judgment efficiency.

[0106] In some embodiments of the present invention, reference Figure 1 , Figure 2 , Figure 7 , Figure 8 , Fig. 9 , Fig.10 When the high-temperature sterilization mode is running, the control unit 3 controls some indoor units 2 to run the low-wind heating mode, and determines the high-temperature sterilization state of each indoor unit 2 running the low-wind heating mode.

[0107] Specifically, the control unit 3 is configured with a second time limit, which is not less than the first time limit. When the high-temperature sterilization mode is running, the second timer is started to count the running time of each indoor unit 2 running the low-wind heating mode. When the timing time of the second timer reaches the second time limit; that is, when the running time of the low-wind heating mode of the indoor unit 2 that is started reaches the second time limit, it is confirmed that the high-temperature sterilization of each corresponding indoor unit 2 is completed, and step S25 is executed to mark it as the indoor unit 2 that has completed high-temperature sterilization, so that the control unit 3 will no longer control the start of the low-wind heating mode in this round of high-temperature sterilization mode and will not detect and judge whether the high-temperature sterilization is completed.

[0108] The control unit 3 is configured with a limit value for the number of continuous starts of the low-wind heating mode in the high-temperature sterilization mode. When the operation of each indoor unit 2 operating in the low-wind heating mode is interrupted during the operation of the high-temperature sterilization mode; that is, when the time for which the indoor unit 2 continues to operate in the low-wind heating mode for high-temperature sterilization does not reach the second time limit, step S26 is executed to record and judge the number of starts of the low-wind heating mode of each indoor unit 2. When the number of continuous starts of each indoor unit 2 operating in the low-wind heating mode reaches the limit value for the number of continuous starts of the low-wind heating mode, step S27 is executed to stop the start of the low-wind heating mode of each indoor unit 2, and determine that the high-temperature sterilization of each indoor unit 2 has failed, and then determine that the high-temperature sterilization of the multi-split air conditioner has failed.

[0109] In this embodiment, the operation interruption of the high-temperature sterilization mode of the multi-split air conditioner may be an external command input interruption or a system operation parameter error interruption.

[0110] The limit value of the number of consecutive starts of the low-wind heating mode in this embodiment can be selected as 3 times.

[0111] The multi-split air conditioner of this embodiment ensures the high-temperature sterilization effect by judging the running time of the indoor unit 2 in the low-wind heating mode. By limiting the number of consecutive starts of the low-wind heating mode, the indoor unit 2 is prevented from being started continuously without limit, thus saving energy and improving user experience.

[0112] In some embodiments of the present invention, reference Figure 1 , Figure 2 , Figure 3 , Figure 4 , Fig.10 The multi-split air conditioner also includes an operation interface 31, which is included in the control unit 3 or is communicated with the control unit 3; the operation interface 31 includes a high-temperature sterilization mode trigger button and a display; when the high-temperature sterilization mode trigger button is operated, the high-temperature sterilization mode is triggered.

[0113] Specifically, when the high-temperature sterilization mode trigger button on the operation interface 31 is operated, the display of the operation interface 31 displays the prompts of exit S11, immediate execution S12, and delayed execution S13, and sets the corresponding operation buttons. That is, when the operation button corresponding to the exit prompt is operated, S3 is executed to exit the high-temperature sterilization mode and return to the initial page of the operation interface 31; when the operation button corresponding to the immediate execution prompt is operated, step S2 is executed to perform the high-temperature sterilization mode control program; when the operation button corresponding to the delayed execution prompt is operated, the operation interface 31 provides the delay time setting, confirmation, and cancellation options; the display shows the delay time setting interface and the delay time can be set and confirmed by operating the corresponding operation button of the operation interface 31.

[0114] When the delay time is set and confirmed, the control unit 3 enters the delay time countdown, and when the countdown reaches zero, executes the high-temperature sterilization mode control program.

[0115] When the high temperature sterilization is completed, the display shows a prompt indicating that the high temperature sterilization is completed. When there is any input in the operation interface 31, S3 exit prompt is executed to return to the initial page of the operation interface 31.

[0116] The multi-split air conditioner of this embodiment sets an operation interface 31 and provides multiple operation options when the high-temperature sterilization trigger button on the operation interface 31 is triggered, so as to meet the diverse needs of users, facilitate user operation, and improve user experience.

[0117] When it is determined that the indoor unit 2 operating in the low-wind heating mode fails in high-temperature sterilization, the control unit 3 controls the operation interface 31 to display a high-temperature sterilization failure prompt and a processing method prompt, and returns to the initial page of the operation interface 31 when any input is made.

[0118] The solution can be to prompt to try again under certain ambient temperature conditions, or to try again after exceeding the set time interval, or to contact after-sales for professional guidance.

[0119] In some embodiments of the present invention, reference Figure 2 The control unit 3 includes an indoor control device 32 and an outdoor control device 33; the indoor control device 32 includes a plurality of indoor controllers and a control panel connected to each indoor controller and arranged on the indoor unit 2, and a wired controller arranged at an easily accessible position indoors; the wired controller is a control panel arranged indoors to conveniently control the indoor unit 2. The outdoor control device 33 includes an outdoor controller. The operation interface 31 can be a wired controller or a wireless remote controller that can wirelessly communicate with the control panel; the operation interface 31 can also be a mobile terminal or a centralized controller equipped with operation software that is connected to the wired controller or the indoor controller or the outdoor controller.

[0120] In some embodiments of the present invention, reference Figure 1 , Figure 2 The first temperature sensor 24, the second temperature sensor 25, and the indoor electronic expansion valve 26 are respectively connected to the corresponding indoor controllers, and the indoor controllers respectively receive the gas pipe temperature Tq, the liquid pipe temperature Ty and the opening control; the four-way valve 12, the compressor 11, and the outdoor electronic expansion valve 15 are respectively connected to the outdoor controller and controlled by the outdoor controller.

[0121] In some embodiments of the present invention, reference Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 , Fig.11 The multi-split air conditioner also includes at least one third temperature sensor 311 and a fourth temperature sensor 14.

[0122] The third temperature sensor 311 is disposed in the room where each indoor unit 2 is located and is connected to the indoor control device 32 for detecting the indoor ambient temperature Ti and transmitting the temperature to the indoor control device 32 .

[0123] The fourth temperature sensor 14 is disposed outdoors where the outdoor unit 1 is located and is connected to the outdoor control device 33 , and is used to detect the outdoor ambient temperature To and transmit the temperature to the outdoor control device 33 .

[0124] The indoor control device 32 is communicatively connected with the outdoor control device 33, and is used to transmit its capacity, coding address and received indoor ambient temperature Ti to the outdoor control device 33; the outdoor control device 33 is configured to determine the ratio of the capacity of the started indoor unit 2 and the capacity of the outdoor unit 1, that is, the capacity of the indoor unit 2, according to the indoor ambient temperature Ti and the outdoor ambient temperature To when running the high-temperature sterilization mode.

[0125] Specifically, the control unit 3 is configured with a plurality of temperature interval threshold combinations and a plurality of capacity ratio thresholds corresponding to each temperature interval threshold combination, to form an ambient temperature capacity ratio threshold correspondence table.

[0126] The temperature interval threshold combination is a combination of the indoor environment temperature threshold and the outdoor environment temperature threshold; the capacity ratio threshold is a threshold range that the ratio of the sum of the capacities of the indoor unit 2 to be started to the capacity of the outdoor unit 1 should satisfy.

[0127] The control unit 3 is configured with multiple indoor ambient temperature thresholds and multiple outdoor ambient temperature thresholds; each outdoor ambient temperature threshold forms at least one outdoor continuous temperature interval; each indoor ambient temperature threshold forms an indoor continuous temperature interval. And each outdoor ambient temperature threshold forming each outdoor continuous temperature interval corresponds to each indoor ambient threshold.

[0128] The control unit 3 of the multi-split air conditioner in this embodiment collects the capacity of each indoor unit 2 and the indoor ambient temperature Ti, and determines the capacity of the indoor unit 2 to be started according to the indoor ambient temperature Ti, the outdoor ambient temperature To and the ambient temperature-capacity ratio threshold correspondence table to adapt to the heating capacity of the multi-split air conditioning system under the ambient temperature.

[0129] In a specific embodiment of the present invention, referring to Figure 2 The third temperature sensor 311 is integrated with the wire controller to detect the indoor environment temperature Ti.

[0130] Of course, the third temperature sensor 311 may also be the fifth temperature sensor 27 provided on the indoor control device 33 and connected to the indoor controller, to detect the indoor ambient temperature Ti at the location of the indoor controller.

[0131] In a specific embodiment of the present invention, referring to Fig.11 , each indoor ambient temperature threshold forms an indoor continuous temperature interval; each outdoor ambient temperature threshold forms a plurality of outdoor continuous temperature intervals; and each indoor ambient temperature threshold corresponds to each outdoor ambient temperature threshold of a different outdoor continuous temperature interval, and each outdoor ambient temperature threshold corresponds to a capacity ratio threshold.

[0132] A specific example is that the indoor ambient temperature threshold includes the interval below 20℃, the interval from 20℃ to 25℃, and the interval above 25℃; the outdoor ambient temperature threshold includes the full temperature interval, the interval below 10℃, the interval from 10℃ to 15℃, the interval from 15℃ to 20℃, the interval from 20℃ to 25℃, the interval below 20℃, and the interval from 20℃ to 30℃; and the full temperature interval is the first outdoor continuous temperature interval; the interval below 10℃, the interval from 10℃ to 15℃, the interval from 15℃ to 20℃, and the interval from 20℃ to 25℃ constitute the second outdoor continuous temperature interval; the interval below 20℃ and the interval from 20℃ to 30℃ constitute the third outdoor continuous temperature interval.

[0133] The interval below 20℃ of the indoor ambient temperature threshold corresponds to the first outdoor continuous temperature interval to form a temperature interval threshold combination; the interval from 20℃ to 25℃ of the indoor ambient temperature threshold corresponds to each outdoor ambient temperature threshold of the second outdoor continuous temperature interval to form each temperature interval threshold combination; the interval above 25℃ of the indoor ambient temperature threshold corresponds to the interval below 20℃ and the interval from 20℃ to 30℃ of the third outdoor continuous temperature interval to form each temperature interval threshold combination. And the above temperature interval threshold combinations correspond to the first capacity ratio threshold, the second capacity ratio threshold, the third capacity ratio threshold, the fourth capacity ratio threshold, the fifth capacity ratio threshold, the sixth capacity ratio threshold, and the seventh capacity ratio threshold. And the fifth capacity ratio threshold and the seventh capacity ratio threshold are all indoor units 2 started.

[0134] The multi-split air conditioner of this embodiment determines the outdoor ambient temperature threshold and indoor ambient temperature threshold at which the indoor ambient temperature Ti and the outdoor ambient temperature To are respectively located, thereby determining the corresponding relationship between their combination and the temperature interval threshold combination, and determining the capacity of the started indoor unit 2 and the capacity ratio threshold relative to the capacity of the outdoor unit 1. Automatically and accurately match the startup capacity of the indoor unit 2 and adapt to the efficiency and capacity of the outdoor unit 1, improve the high-temperature sterilization efficiency, and enhance the user experience.

[0135] In some embodiments of the present invention, referring to Fig.11 The first capacity ratio threshold, the second capacity ratio threshold, the third capacity ratio threshold, the fourth capacity ratio threshold, and the sixth capacity ratio threshold are all thresholds adapted to each indoor unit 2 matched with the outdoor unit 1 of the multi-split air conditioner, and include a basic value and an amplitude value respectively; the basic value is the middle value of the threshold; the amplitude value is the amplitude on both sides of the middle value. And the amplitude value is obtained by the ratio of the capacity of the indoor unit 2 with the smaller capacity among the capacities of each indoor unit 2 matched with the multi-split air conditioner to the capacity of the outdoor unit 1.

[0136] The multi-split air conditioner of this embodiment adapts to the capacity of each indoor unit 2 matched with the outdoor unit 1, selects a smaller ratio of the capacity of the indoor unit 2 to the capacity of the outdoor unit 1 and sets it as the amplitude value on both sides of the middle value of the capacity ratio threshold, increases the probability that the capacity of the started indoor unit 2 and the ratio of the capacity of the outdoor unit 1 fall within the capacity ratio threshold range, and improves the control efficiency and the reliability of the control system operation.

[0137] In some embodiments of the present invention, referring to Figure 4 , Figure 5 , Figure 6 , each indoor unit 2 of the multi-split air conditioner is configured with a different coding address, which can be automatically allocated by the outdoor unit 1 to each indoor unit 2, or manually set by the wired controller or the indoor control device 33; the control unit 3 collects the coding address of each indoor unit 2 and its corresponding capacity value, and is configured to add the indoor unit 2 to the startup list of the low-wind heating mode in the high-temperature sterilization mode one by one according to the coding address, and judge whether the ratio of the capacity of each indoor unit 2 in the startup list to the capacity of the outdoor unit 1 is within the capacity ratio threshold range determined according to the outdoor ambient temperature To and the indoor ambient temperature Ti; when it is within the capacity ratio threshold range, execute step S21 to start each indoor unit 2 in the startup list to operate in the low-wind heating mode. When it is not within the capacity ratio threshold range, execute step S22 to adjust the indoor units in the startup list.

[0138] Specifically, the control unit 3 sorts the coding addresses of each indoor unit 2. The sorting method can be performed according to the size of the coding address, or according to the size of the capacity of the indoor unit 2 corresponding to the coding address; the control unit 3 is configured to select the first indoor unit 2 according to the sorting of the coding address and add it to the startup list.

[0139] The capacity of the indoor unit 2 in the startup list is judged; if the ratio of its capacity to that of the outdoor unit 1 reaches the lower limit of the capacity ratio threshold, execute step S211 to start the indoor unit 2 in the current startup list; if the ratio of its capacity to that of the outdoor unit 1 does not reach the lower limit of the capacity ratio threshold, add an indoor unit 2 to the startup list in the order of the coding address sorting, and judge the sum of the capacities of the indoor units 2 in the current startup list.

[0140] If the ratio of the capacity of the indoor unit 2 in the startup list to the capacity of the outdoor unit 1 is within the capacity ratio threshold range, step S211 is executed to start each indoor unit 2 in the current startup list.

[0141] If the ratio of the capacity of each indoor unit 2 in the startup list to the capacity of the outdoor unit 1 reaches the upper limit of the capacity ratio threshold, execute step S222 to determine whether the added indoor unit 2 is the last indoor unit 2 without the high-temperature sterilization completion mark; if yes, execute step S211 to start each indoor unit 2 in the current startup list; if not, execute step S212 to start each indoor unit 2 in the startup list before adding this indoor unit 2.

[0142] If the capacity of each indoor unit 2 in the startup list and the ratio of the capacity to the outdoor unit 1 do not reach the lower limit of the threshold, execute step S223 to determine whether the added indoor unit 2 is the last indoor unit 2 of the indoor units 2 that are not marked as having completed high-temperature sterilization; if so, execute step S211 to start each indoor unit 2 in the current startup list; if not, execute step S221 to add the next indoor unit 2 that is not marked as having completed high-temperature sterilization into the startup list according to the coding address sequence, and then determine the capacity of each indoor unit 2 in the added startup list and the ratio of the capacity to the outdoor unit 1.

[0143] In the description of the above embodiments, specific features, structures, materials or characteristics may be combined in a suitable manner in any one or more embodiments or examples.

[0144] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A multi-split air conditioner, characterized in that: include: An outdoor unit, which includes a compressor, a four-way valve, and an outdoor heat exchanger; Multiple indoor units; The indoor unit includes an indoor heat exchanger; A plurality of air pipes, one end of which is respectively connected to the same port of the four-way valve, and the other end of which is respectively connected to one end of each of the indoor heat exchangers; A plurality of liquid pipes, one end of which is respectively connected to the same port of the outdoor heat exchanger, and the other end of which is respectively connected to the other end of each of the indoor heat exchangers; A plurality of first temperature sensors, which are respectively arranged on each of the air pipes and are used to detect the temperature of the air pipe where they are located; the measured temperature of the air pipe is recorded as the air pipe temperature; A plurality of second temperature sensors, which are respectively arranged on each of the liquid pipes and are used to detect the temperature of the liquid pipe where they are located; the measured temperature of the liquid pipe is recorded as the liquid pipe temperature; A control unit is configured with an air pipe temperature limit, a liquid pipe temperature limit, and a first time limit; the control unit is respectively connected to each of the first temperature sensors and each of the second temperature sensors, receives each of the air pipe temperatures and each of the liquid pipe temperatures, and is configured to determine whether the air pipe temperature and the liquid pipe temperature of the indoor unit that is not in operation are respectively within the air pipe temperature limit and the liquid pipe temperature limit; if so, determine whether the duration of the air pipe temperature and the liquid pipe temperature being respectively within the air pipe temperature limit and the liquid pipe temperature limit reaches the first time limit; if so, determine that the high-temperature sterilization of the indoor unit is completed; if not, determine that the high-temperature sterilization of the indoor unit is not completed.

2. The multi-split air conditioner according to claim 1, characterized in that: The control unit is configured with a high-temperature sterilization mode, and when the high-temperature sterilization mode is running, the control unit controls the indoor unit to run a low-wind heating mode, so as to sterilize the indoor heat exchanger at high temperature; The control unit is also configured to judge whether the gas pipe temperature and the liquid pipe temperature of each of the indoor units that are not running the low-wind heating mode are within the gas pipe temperature limit and the liquid pipe temperature limit, respectively; if so, then judge whether the duration of the gas pipe temperature and the liquid pipe temperature of each of the indoor units that are not running the low-wind heating mode within the gas pipe temperature limit and the liquid pipe temperature limit, respectively, reaches the first time limit, which is used to judge whether the high-temperature sterilization of each of the indoor units that are not running in the high-temperature sterilization mode has been completed.

3. The multi-split air conditioner according to claim 2, characterized in that: The control unit is configured with a second time limit and a low-wind heating mode continuous start-up times limit; the second time limit is not less than the first time limit; When the high-temperature sterilization mode is run, the continuous operation time of each indoor unit running the low-wind heating mode is obtained and recorded as the sterilization time; comparing the sterilization time with the second time limit; when the sterilization time reaches the second time limit, determining that the high-temperature sterilization of the indoor unit is completed; When the sterilization time does not reach the second time limit, recording the number of consecutive starts of the indoor unit in the low-air heating mode, and comparing the number of consecutive starts with the limit of the number of consecutive starts in the low-air heating mode; When the number of consecutive starts does not exceed the limit of the number of consecutive starts of the low-wind heating mode, restarting the low-wind heating mode; When the number of consecutive starts exceeds the limit of the number of consecutive starts of the low-airflow heating mode, the low-airflow heating mode is stopped and it is determined that the high-temperature sterilization of the indoor unit has failed.

4. The multi-split air conditioner according to claim 2 or 3, characterized in that: Also includes at least a third temperature sensor and a fourth temperature sensor; The third temperature sensor is used to detect the indoor ambient temperature; the fourth temperature sensor is used to detect the outdoor ambient temperature; The control unit is connected to the third temperature sensor and the fourth temperature sensor respectively, and receives the indoor ambient temperature and the outdoor ambient temperature detected by them; and is configured to determine the capacity of the indoor unit running the low-wind heating mode and the ratio to the capacity of the outdoor unit according to the indoor ambient temperature and the outdoor ambient temperature when running the high-temperature sterilization mode.

5. The multi-split air conditioner according to claim 4, characterized in that: The control unit is configured with a plurality of temperature interval threshold combinations and a plurality of capacity ratio thresholds corresponding to each of the temperature interval threshold combinations; the temperature interval threshold combination is a combination of an indoor ambient temperature threshold and an outdoor ambient temperature threshold; the control unit is configured with a plurality of the indoor ambient temperature thresholds and a plurality of the outdoor ambient temperature thresholds; each of the outdoor ambient temperature thresholds forms at least one outdoor continuous temperature interval; each of the indoor ambient temperature thresholds forms an indoor continuous temperature interval; The control unit is configured to determine the capacity ratio threshold value according to the received indoor ambient temperature and the received outdoor ambient temperature; And it is configured to determine the sum of the capacities of the indoor units started in the high-temperature sterilization mode according to the capacity ratio threshold.

6. The multi-split air conditioner according to claim 5, characterized in that: Each of the capacity ratio thresholds includes a basic value and an amplitude value; the basic value is the middle value of the capacity ratio threshold; the amplitude value is the ratio of the smaller capacity of each of the indoor units to the capacity of the outdoor unit, and is used to limit the amplitude on both sides of the basic value; Each of the indoor units is respectively configured with a different coding address; The control unit collects the coding address and capacity value of each indoor unit; And it is configured to add the indoor units to the startup list of the low-wind heating mode one by one according to the coding address, so that the ratio of the sum of the capacities of each indoor unit in the startup list to the capacity of the outdoor unit meets the requirement of the capacity ratio threshold for the sum of the capacities of each indoor unit.

7. The multi-split air conditioner according to claim 6, characterized in that: When the high temperature sterilization mode is run to determine the startup list: If the ratio of the capacity of the first added indoor unit to the capacity of the outdoor unit reaches the upper limit of the capacity ratio threshold, starting the indoor unit in the current start-up list; If the ratio of the capacity of each indoor unit in the startup list to the capacity of the outdoor unit does not reach the lower limit of the capacity ratio threshold, determining whether it is the last indoor unit; If yes, start with the current startup list; if no, continue to add the indoor unit; If the ratio of the capacity of each of the indoor units in the startup list to the capacity of the outdoor unit reaches the upper limit of the capacity ratio threshold, determining whether it is the last indoor unit; If yes, start with the current startup list; if no, start with the startup list before adding the indoor unit.

8. The multi-split air conditioner according to claim 2 or 3, characterized in that: Also included is an operation interface, which is included in the control unit or connected to the control unit, including a high-temperature sterilization button and a display, and is used to trigger the high-temperature sterilization mode when the high-temperature sterilization button is operated; When the high-temperature sterilization mode is triggered, the display provides exit, immediate execution, and delayed execution options, which are respectively used to exit the high-temperature sterilization mode, enter the high-temperature sterilization mode, and delay entering the high-temperature sterilization mode.

9. The multi-split air conditioner according to claim 8, characterized in that: When the delayed execution option is selected, the operation interface provides delay duration setting, confirmation and cancellation options; When the delay time setting is operated and confirmed, the control unit controls the countdown to enter the high-temperature sterilization mode; When the countdown is completed, the high temperature sterilization mode is immediately entered; When cancel is selected, the high temperature sterilization mode is exited.

10. The multi-split air conditioner according to claim 9, characterized in that: The operation interface also includes a plurality of operation mode setting buttons; When any of the operation mode setting buttons is operated during the high-temperature sterilization mode, the high-temperature sterilization mode is exited; When the high-temperature sterilization of all the indoor units is completed, the operation interface gives a high-temperature sterilization success prompt; when the high-temperature sterilization of the indoor units fails, the operation interface gives a high-temperature sterilization failure prompt; when any of the operation mode setting buttons is operated, the high-temperature sterilization success or failure prompt is exited.

Images