Diagnostics of outdoor unit of HVAC system based on sound signatures

Abstract

A method for heating, ventilation, and air conditioning (HVAC) system diagnostics includes sending a first instruction to a thermostat to shut down an HVAC system. A user is instructed to minimize background noise. A second instruction is sent to the thermostat to turn on the HVAC system. A third instruction is sent to the thermostat to set a temperature setpoint below or above a value of a room temperature. Outdoor unit sound data is captured for a second time period. The baseline sound data is subtracted from the outdoor unit sound data to determine normalized outdoor unit sound data. Expected sound signatures of the outdoor unit are identified. The normalized outdoor unit sound data is compared to the expected sound signatures. In response to determining that an expected sound signature for a compressor is missing from the normalized outdoor unit sound data, it is determined that the compressor has failed.

1 . A system comprising:
 a thermostat communicatively coupled to a heating, ventilation, and air conditioning (HVAC) system;   a device communicatively coupled to the thermostat, wherein the device comprises a first processor configured to:
 send a first instruction to the thermostat to shut down the HVAC system; 
 capture baseline sound data for a first time period; 
 send a second instruction to the thermostat to turn on the HVAC system; 
 determine a value of a room temperature; 
 send a third instruction to the thermostat to set a temperature setpoint below or above the value of the room temperature; 
 capture first outdoor unit sound data for a second time period; and 
 send the first outdoor unit sound data and the baseline sound data to a computing system; and 
   the computing system communicatively coupled to the device, wherein the computing system comprises a second processor configured to:
 subtract the baseline sound data from the first outdoor unit sound data to determine first normalized outdoor unit sound data; 
 analyze the first normalized outdoor unit sound data to determine first sound signatures; 
 identify expected first sound signatures of the outdoor unit; 
 compare the first normalized outdoor unit sound data to the expected first sound signatures; 
 in response to determining that an expected sound signature for a compressor is missing from the first normalized outdoor unit sound data, determine that the compressor has failed; and 
 send a first notification indicating that the compressor has failed. 
   
     
     
         2 . The system of  claim 1 , wherein the second processor is further configured to:
 in response to determining that the expected sound signature for the compressor is not missing from the first normalized outdoor unit sound data:
 in response to determining that the expected sound signature for the compressor is different from a respective sound signature of the compressor determined from the first normalized outdoor unit sound data, determine that the compressor is malfunctioning; and 
 send a second notification indicating that compressor is malfunctioning. 
   
     
     
         3 . The system of  claim 2 , wherein the second processor is further configured to:
 in response to determining that the expected sound signature for the compressor is not different from the respective sound signature of the compressor determined from the first normalized outdoor unit sound data:
 in response to determining that an expected sound signature for an outdoor fan is missing from the first normalized outdoor unit sound data, determine that the outdoor fan has failed; and 
 send a third notification indicating that the outdoor fan has failed. 
   
     
     
         4 . The system of  claim 3 , wherein the second processor is further configured to:
 in response to determining that the expected sound signature for the outdoor fan is not missing from the first normalized outdoor unit sound data:
 in response to determining that the expected sound signature for the outdoor fan is different from a respective sound signature of the outdoor fan determined from the first normalized outdoor unit sound data, determine that the outdoor fan is malfunctioning; and 
 send a fourth notification indicating that the outdoor fan is malfunctioning. 
   
     
     
         5 . The system of  claim 4 , wherein the second processor is further configured to:
 in response to determining that the expected sound signature for the outdoor fan is not different from the respective sound signature of the outdoor fan determined from the first normalized outdoor unit sound data:
 determine that the outdoor unit operates properly; and 
 send a fifth notification indicating that the outdoor unit operates properly. 
   
     
     
         6 . The system of  claim 4 , wherein the second processor is further configured to:
 in response to determining that the expected sound signature for the outdoor fan is not different from the respective sound signature of the outdoor fan determined from the first normalized outdoor unit sound data:
 in response to determining that the temperature setpoint is less than the value of the room temperature:
 send a fourth instruction to the thermostat to set the temperature setpoint above the value of the room temperature; 
 capture second outdoor unit sound data for a third time period; 
 subtract the baseline sound data from the second outdoor unit sound data to determine second normalized outdoor unit sound data; 
 analyze the second normalized outdoor unit sound data to determine second sound signatures; 
 identify expected second sound signatures of the outdoor unit; 
 compare the second normalized outdoor unit sound data to the expected second sound signatures; 
 in response to determining that an expected sound signature for a reversing valve is missing from the second normalized outdoor unit sound data, determine that the reversing valve has failed; and 
 send a fifth notification indicating that the reversing valve has failed. 
 
   
     
     
         7 . The system of  claim 6 , wherein the second processor is further configured to:
 in response to determining that the expected sound signature for the reversing valve is not missing from the second normalized outdoor unit sound data:
 in response to determining that the expected sound signature for the reversing valve is different from a respective sound signature of the reversing valve determined from the second normalized outdoor unit sound data, determine that the reversing valve is malfunctioning; and 
 send a sixth notification indicating that reversing valve is malfunctioning. 
   
     
     
         8 . A method comprising:
 sending a first instruction to a thermostat to shut down a heating, ventilation, and air conditioning (HVAC) system;   capturing baseline sound data for a first time period;   sending a second instruction to the thermostat to turn on the HVAC system;   determining a value of a room temperature;   sending a third instruction to the thermostat to set a temperature setpoint below or above the value of the room temperature;   capturing first outdoor unit sound data for a second time period;   subtracting the baseline sound data from the first outdoor unit sound data to determine first normalized outdoor unit sound data;   analyzing the first normalized outdoor unit sound data to determine first sound signatures;   identifying expected first sound signatures of the outdoor unit;   comparing the first normalized outdoor unit sound data to the expected first sound signatures;   in response to determining that an expected sound signature for a compressor is missing from the first normalized outdoor unit sound data, determining that the compressor has failed; and   sending a first notification indicating that the compressor has failed.   
     
     
         9 . The method of  claim 8 , further comprising:
 in response to determining that the expected sound signature for the compressor is not missing from the first normalized outdoor unit sound data:
 in response to determining that the expected sound signature for the compressor is different from a respective sound signature of the compressor determined from the first normalized outdoor unit sound data, determining that the compressor is malfunctioning; and 
 sending a second notification to the device that compressor is malfunctioning. 
   
     
     
         10 . The method of  claim 9 , further comprising:
 in response to determining that the expected sound signature for the compressor is not different from the respective sound signature of the compressor determined from the first normalized outdoor unit sound data:
 in response to determining that an expected sound signature for an outdoor fan is missing from the first normalized outdoor unit sound data, determining that the outdoor fan has failed; and 
 sending a third notification to the device that the outdoor fan has failed. 
   
     
     
         11 . The method of  claim 10 , further comprising:
 in response to determining that the expected sound signature for the outdoor fan is not missing from the first normalized outdoor unit sound data:
 in response to determining that the expected sound signature for the outdoor fan is different from a respective sound signature of the outdoor fan determined from the first normalized outdoor unit sound data, determining that the outdoor fan is malfunctioning; and 
 sending a fourth notification to the device that the outdoor fan is malfunctioning. 
   
     
     
         12 . The method of  claim 11 , further comprising:
 in response to determining that the expected sound signature for the outdoor fan is not different from the respective sound signature of the outdoor fan determined from the first normalized outdoor unit sound data:
 determining that the outdoor unit operates properly; and 
 sending a fifth notification to the device that the outdoor unit operates properly. 
   
     
     
         13 . The method of  claim 11 , further comprising:
 in response to determining that the expected sound signature for the outdoor fan is not different from the respective sound signature of the outdoor fan determined from the first normalized outdoor unit sound data:
 in response to determining that the temperature setpoint is less than the value of the room temperature:
 sending a fourth instruction to the thermostat to set the temperature setpoint above the value of the room temperature; 
 capturing second outdoor unit sound data for a third time period; 
 subtracting the baseline sound data from the second outdoor unit sound data to determine second normalized outdoor unit sound data; 
 analyzing the second normalized outdoor unit sound data to determine second sound signatures; 
 identifying expected second sound signatures of the outdoor unit; 
 comparing the second normalized outdoor unit sound data to the expected second sound signatures; 
 in response to determining that an expected sound signature for a reversing valve is missing from the second normalized outdoor unit sound data, determining that the reversing valve has failed; and 
 
 sending a fifth notification indicating that the reversing valve has failed. 
   
     
     
         14 . The method of  claim 13 , further comprising:
 in response to determining that the expected sound signature for the reversing valve is not missing from the second normalized outdoor unit sound data:
 in response to determining that the expected sound signature for the reversing valve is different from a respective sound signature of the reversing valve determined from the second normalized outdoor unit sound data, determining that the reversing valve is malfunctioning; and 
 sending a sixth notification indicating that reversing valve is malfunctioning. 
   
     
     
         15 . A non-transitory computer-readable medium storing instructions that, when executed by one or more processors, cause the one or more processors to:
 send a first instruction to a thermostat to shut down a heating, ventilation, and air conditioning (HVAC) system;   capture baseline sound data for a first time period;   send a second instruction to the thermostat to turn on the HVAC system;   determine a value of a room temperature;   send a third instruction to the thermostat to set a temperature setpoint below or above the value of the room temperature;   capture first outdoor unit sound data for a second time period;   subtract the baseline sound data from the first outdoor unit sound data to determine first normalized outdoor unit sound data;   analyze the first normalized outdoor unit sound data to determine first sound signatures;   identify expected first sound signatures of the outdoor unit;   compare the first normalized outdoor unit sound data to the expected first sound signatures;   in response to determining that an expected sound signature for a compressor is missing from the first normalized outdoor unit sound data, determine that the compressor has failed; and   send a first notification indicating that the compressor has failed.   
     
     
         16 . The non-transitory computer-readable medium of  claim 15 , wherein the instructions, when executed by the one or more processors, further cause the one or more processors to:
 in response to determining that the expected sound signature for the compressor is not missing from the first normalized outdoor unit sound data:
 in response to determining that the expected sound signature for the compressor is different from a respective sound signature of the compressor determined from the first normalized outdoor unit sound data, determine that the compressor is malfunctioning; and 
 send a second notification indicating that compressor is malfunctioning. 
   
     
     
         17 . The non-transitory computer-readable medium of  claim 16 , wherein the instructions, when executed by the one or more processors, further cause the one or more processors to:
 in response to determining that the expected sound signature for the compressor is not different from the respective sound signature of the compressor determined from the first normalized outdoor unit sound data:
 in response to determining that an expected sound signature for an outdoor fan is missing from the first normalized outdoor unit sound data, determine that the outdoor fan has failed; and 
 send a third notification indicating that the outdoor fan has failed. 
   
     
     
         18 . The non-transitory computer-readable medium of  claim 17 , wherein the instructions, when executed by the one or more processors, further cause the one or more processors to:
 in response to determining that the expected sound signature for the outdoor fan is not missing from the first normalized outdoor unit sound data:
 in response to determining that the expected sound signature for the outdoor fan is different from a respective sound signature of the outdoor fan determined from the first normalized outdoor unit sound data, determine that the outdoor fan is malfunctioning; and 
 send a fourth notification indicating that the outdoor fan is malfunctioning. 
   
     
     
         19 . The non-transitory computer-readable medium of  claim 18 , wherein the instructions, when executed by the one or more processors, further cause the one or more processors to:
 in response to determining that the expected sound signature for the outdoor fan is not different from the respective sound signature of the outdoor fan determined from the first normalized outdoor unit sound data:
 determine that the outdoor unit operates properly; and 
 send a fifth notification indicating that the outdoor unit operates properly. 
   
     
     
         20 . The non-transitory computer-readable medium of  claim 18 , wherein the instructions, when executed by the one or more processors, further cause the one or more processors to:
 in response to determining that the expected sound signature for the outdoor fan is not different from the respective sound signature of the outdoor fan determined from the first normalized outdoor unit sound data:
 in response to determining that the temperature setpoint is less than the value of the room temperature:
 send a fourth instruction to the thermostat to set the temperature setpoint above the value of the room temperature; 
 capture second outdoor unit sound data for a third time period; 
 subtract the baseline sound data from the second outdoor unit sound data to determine second normalized outdoor unit sound data; 
 analyze the second normalized outdoor unit sound data to determine second sound signatures; 
 identify expected second sound signatures of the outdoor unit; 
 compare the second normalized outdoor unit sound data to the expected second sound signatures; 
 in response to determining that an expected sound signature for a reversing valve is missing from the second normalized outdoor unit sound data, determine that the reversing valve has failed; and 
 
 send a fifth notification indicating that the reversing valve has failed.