Indoor unit Operation  Cooling oil return operation 
Status  Fan  Electronic Expansion Valve 
Thermal ON  OFF  480P 
OFF  OFF  480P 
Thermal OFF  OFF  480P 
Defrost starting condition:  Defrost operation is started when the outdoor heat exchanger temperature becomes lower than 
threshold temperature. Defrost operation is conducted once in a maximum of 2 hours. 
Table 27 - Restart Standby 
Component  Cooling Operation  Heating Operation 
Compressor  OFF  OFF 
Outdoor unit fan (FAN A)  OFF 
OFF 
Outdoor unit fan (FAN B)  OFF  OFF 
Four way valve (ST1)  OFF 
Holds 
Electronic expansion valve (EXV A)  350P  Initial pulse step 
Electronic expansion valve (EXV B)  350P  Initial pulse step 
Electronic expansion valve (EXV C)  0P  0P 
Solenoid valve (SV4)  OFF  OFF 
Solenoid valve (SV7)  OFF  OFF 
Ending conditions  12 minutes  12 minutes 
3. Overload Control 
To maintain the required set point, the air flow of all indoor units are set to low speed if the connected capacity of the indoor 
units is more than 120%. However, the air flow of the indoor units will return to normal once the connected capacity of 
indoor unit is less than 105%. 
4. Stopping Operation 
Table 28 - When System is in Stop Mode 
Compressor  OFF 
Outdoor unit fan (FAN A)  OFF 
Outdoor unit fan (FAN B)  OFF 
Four way valve (ST1)  OFF 
Electronic expansion valve (EXV A)  350P 
Electronic expansion valve (EXV B)  350P 
Electronic expansion valve (EXV C)  0P 
Solenoid valve (SV4)  OFF 
Solenoid valve (SV7)  OFF 
Ending conditions  Indoor unit thermostat is turned ON 
Stop operation of follower units while header unit is still in operation in a modular system. 
   
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