Malfunction explanation   
Error symbals 
Anomaly 
Running Heating Cooling
 
Indoor
Outdoor
Automatic 
restore 
Causes 
Indoor thermister 
anomaly  
★ ■ ■  *    *  1.   
Poor connection of the 
connectors or bad control 
base plate 
Heat-exchange 
thermister 
anomaly 
★ □ □  *    *  1.Poor connection of the 
connectors or bad control 
base plate 
Frost-removing 
thermister 
anomaly  
□ □ ★    *  *  1.Poor connection of the 
connectors or bad control 
base plate 
Output thermister 
anomaly 
★ □ ■    *  *  1.Poor connection of the 
connectors or bad control  
base plate 
Base plate 
thermister 
anomaly 
□ ■ ★    *  *  1.Poor connection of the 
connectors or bad control  
base plate 
Module 
thermister 
anomaly 
□ ★ □    *  *  1.Poor connection of the 
connectors or 
base plate 
Outdoor 
thermister 
anomaly 
□ ★ ■    *  *  1.Poor connection of the 
connectors or bad control  
base plate 
*     
1.Poor connection of the 
connectors or bad control 
base plate 
Transmition error
■ ■ ★ 
  *    2.Wrong wiring or bad 
base plate 
Anomaly of 
compressor 
running  
★ ■ □    *    1.If there is any seize 
of the compressor 
2.If there are any 
damages of  power 
module 
 
Model:
HSU-12HS03/R2(DB)
HSU-09HS03/R2(DB)Domestic Air Conditioner