Detection method, control device and air conditioning system of air conditioning system

Abstract

This application provides a detection method of an air conditioning system. When the air conditioning system is operating in a cooling mode and a fan of an indoor unit and an expansion valve need to be detected or debugged. When a difference between a return air temperature of the indoor unit and a heat exchanger coil temperature of the indoor unit within the first specified duration is greater than a specified fan determination threshold, it is determined that the fan of the indoor unit is faulty. A difference between a return air temperature difference of the first indoor unit and a heat exchanger coil temperature difference of the first indoor unit is detected, and when the difference is less than a specified expansion valve determination threshold, it is determined that the first expansion valve is faulty.

What is claimed is: 
     
         1 . A detection method of an air conditioning system, the air conditioning system including a compressor, an outdoor unit, a first indoor unit and a second indoor unit connected to the compressor through a refrigerant circulation loop, and a first expansion valve and a second expansion valve respectively provided corresponding to the first indoor unit and the second indoor unit, the detection method comprising:
 an air conditioning system operation mode determination step of determining whether the air conditioning system is in a specified mode;   a compressor first rotating speed operating control step of maintaining the compressor to operate at a first specified rotating speed for a first specified duration, instructing a fan of the first indoor unit and a fan of the second indoor unit to maintain the same specified fan rotating speed within the first specified duration, and instructing opening degrees of the first expansion valve and the second expansion valve to maintain the same first specified expansion valve opening degree;   an indoor unit fan operating condition detection step of, within the first specified duration, separately detecting a return air temperature of the first indoor unit and a heat exchanger coil temperature of the first indoor unit and comparing a difference therebetween, and detecting a return air temperature of the second indoor unit and a heat exchanger coil temperature of the second indoor unit and comparing a difference therebetween;   an indoor unit fan operating condition determination step of determining whether the fan of the first indoor unit and the fan of the second indoor unit operate normally according to detection and comparison results in the indoor unit fan operating condition detection step;   a compressor second rotating speed operating control step of instructing the compressor to operate at a second specified rotating speed higher than the first specified rotating speed after the first specified duration has elapsed;   a first expansion valve adjustment step of instructing the first expansion valve to close, instructing the first expansion valve to be adjusted to a second specified expansion valve opening degree after the first expansion valve is closed and a second specified duration has elapsed, and maintaining the second specified expansion valve opening degree for a third specified duration;   a first expansion valve operating condition detection step of, within the second specified duration and the third specified duration, separately detecting the return air temperature of the first indoor unit and acquiring a return air temperature difference of the first indoor unit, and detecting the heat exchanger coil temperature of the first indoor unit and acquiring a heat exchanger coil temperature difference of the first indoor unit; and   a first expansion valve operating condition determination step of determining that the first expansion valve is faulty when a first difference between the return air temperature difference of the first indoor unit and the heat exchanger coil temperature difference of the first indoor unit is less than a specified expansion valve determination threshold.   
     
     
         2 . The detection method of an air conditioning system according to  claim 1 , the detection method further comprising:
 a second expansion valve adjustment step of instructing the second expansion valve to close, instructing the second expansion valve to be adjusted to the second specified expansion valve opening degree after the second expansion valve is closed and the second specified duration has elapsed, and maintaining the second specified expansion valve opening degree for the third specified duration;   a second expansion valve operating condition detection step of, within the second specified duration and the third specified duration, separately detecting the return air temperature of the second indoor unit and acquiring a return air temperature difference of the second indoor unit, and detecting the heat exchanger coil temperature of the second indoor unit and acquiring a heat exchanger coil temperature difference of the second indoor unit; and   a second expansion valve operating condition determination step of determining that the second expansion valve is faulty when a second difference between the return air temperature difference of the second indoor unit and the heat exchanger coil temperature difference of the second indoor unit is less than the specified expansion valve determination threshold.   
     
     
         3 . The detection method of an air conditioning system according to  claim 2 , wherein
 when the second expansion valve adjustment step is executed, an opening degree of the first expansion valve is instructed to be adjusted to a third specified expansion valve opening degree greater than the second specified expansion valve opening degree.   
     
     
         4 . The detection method of an air conditioning system according to  claim 1 , wherein
 the specified mode is a cooling mode.   
     
     
         5 . The detection method of an air conditioning system according to  claim 4 , wherein
 in the indoor unit fan operating condition determination step,   when the difference between the return air temperature of the first indoor unit and the heat exchanger coil temperature of the first indoor unit, or the difference between the return air temperature of the second indoor unit and the heat exchanger coil temperature of the second indoor unit is greater than a specified fan determination threshold, it is determined that the fan of the first indoor unit or the fan of the second indoor unit is faulty.   
     
     
         6 . The detection method of an air conditioning system according to  claim 5 , wherein
 the second specified expansion valve opening degree is a minimum opening degree of the first expansion valve and/or the second expansion valve.   
     
     
         7 . The detection method of an air conditioning system according to  claim 6 , wherein
 the first specified expansion valve opening degree is a specified opening degree between a maximum opening degree and the minimum opening degree of the first expansion valve and/or the second expansion valve.   
     
     
         8 . The detection method of an air conditioning system according to  claim 7 , wherein
 the specified fan rotating speed is a highest rotating speed of the fan of the first indoor unit and the fan of the second indoor unit.   
     
     
         9 . The detection method of an air conditioning system according to  claim 2 , wherein the air conditioning system further includes: a third indoor unit and a fourth indoor unit connected to the compressor through a refrigerant circulation loop; and a third expansion valve and a fourth expansion valve respectively provided corresponding to the third indoor unit and the fourth indoor unit, and the detection method further comprises:
 a third expansion valve adjustment step and a fourth expansion valve adjustment step; 
 a third expansion valve operating condition detection step and a fourth expansion valve detection step; and 
 a third expansion valve operating condition determination step and a fourth expansion valve operating condition determination step. 
 
     
     
         10 . A control device of an air conditioning system, the air conditioning system including a compressor, an outdoor unit, a first indoor unit and a second indoor unit connected to the compressor through a refrigerant circulation loop, and a first expansion valve and a second expansion valve respectively provided corresponding to the first indoor unit and the second indoor unit,
 the control device comprising:   an air conditioning system operating mode determination module configured to determine whether the air conditioning system is in a specified mode;   a compressor first rotating speed operating control module configured to maintain the compressor to operate at a first specified rotating speed for a first specified duration, instruct a fan of the first indoor unit and a fan of the second indoor unit to maintain the same specified fan rotating speed within the first specified duration, and instruct opening degrees of the first expansion valve and the second expansion valve to maintain the same first specified expansion valve opening degree;   an indoor unit fan operating condition detection module configured to, within the first specified duration, separately detect a return air temperature of the first indoor unit and a heat exchanger coil temperature of the first indoor unit and compare a difference therebetween, and detect a return air temperature of the second indoor unit and a heat exchanger coil temperature of the second indoor unit and compare a difference therebetween;   an indoor unit fan operating condition determination module configured to determine whether the fan of the first indoor unit and the fan of the second indoor unit operate normally according to detection and comparison results in the indoor unit fan operating condition detection module;   a compressor second rotating speed operating control module configured to instruct the compressor to operate at a second specified rotating speed higher than the first specified rotating speed after the first specified duration has elapsed;   a first expansion valve adjustment module configured to instruct the first expansion valve to close, instruct the first expansion valve to be adjusted to a second specified expansion valve opening degree of the expansion valve after the first expansion valve is closed and a second specified duration has elapsed, and maintain the second specified expansion valve opening degree of the expansion valve for a third specified duration;   a first expansion valve operating condition detection module configured to, within the second specified duration and the third specified duration, separately detect the return air temperature of the first indoor unit and acquire a return air temperature difference of the first indoor unit, and detect the heat exchanger coil temperature of the first indoor unit and acquire a heat exchanger coil temperature difference of the first indoor unit; and   a first expansion valve operating condition determination module configured to determine that the first expansion valve is faulty when a first difference between the return air temperature difference of the first indoor unit and the heat exchanger coil temperature difference of the first indoor unit is less than a specified expansion valve determination threshold.   
     
     
         11 . An air conditioning system comprising: a memory; and a controller, wherein the controller executes the detection method of an air conditioning system according to  claim 1 . 
     
     
         12 . An air conditioning system comprising:
 a first indoor unit comprising a first expansion valve and a first heat exchanger;   a second indoor unit comprising a second expansion valve and a second heat exchanger;   a memory; and   a controller configured to:
 determine a return air temperature and a heat exchanger coil temperature of the first indoor unit and the second indoor unit; and 
 determine a fault of the first indoor unit or the second indoor unit based on a difference between the return air temperature and the heat exchanger coil temperature. 
   
     
     
         13 . The air conditioning system according to  claim 12 , further comprising an outdoor unit comprising a compressor; and
 wherein the controller is further configured to:
 control a rotating speed of the compressor between multiple speeds. 
   
     
     
         14 . The air conditioning system according to  claim 12 , wherein the controller is further configured to:
 determine a fault of the first expansion valve or the second expansion valve based on the difference between the return air temperature and the heat exchanger coil temperature.   
     
     
         15 . The air conditioning system according to  claim 12 , wherein the air conditioning system further comprises three or more indoor units.