2. Basic Control 
a.  Normal Operation 
Table 4 - Cooling Operation 
Component  Operation  Remarks 
Compressor  Cooling Compressor control 
Used for high pressure protection control, discharge pipe 
temperature protection control, and compressor operating 
frequency upper limit control with inverter protection control. 
Outdoor unit fan (FAN A)  Cooling fan control   
Outdoor unit fan (FAN B)  Cooling fan control   
Four way valve (ST1)  OFF   
Electronic expansion valve (EXV A)  350P   
Electronic expansion valve (EXV B)  350P   
Electronic expansion valve (EXV C)  PI control   
Solenoid valve (SV4) 
17 minutes OFF,3 minutes ON 
 
Solenoid valve (SV7) 
Pc ≥ 536.6 psi ON,Pc < 478.6 psi OFF 
 
Table 5 - Heating Operation   
Component  Operation  Remarks 
Compressor  Heating Compressor control 
Used for high pressure protection control, low pressure 
protection control, discharge pipe temperature protection 
control, and compressor operating frequency upper limit 
control with inverter protection control. 
Outdoor unit fan (FAN B)  Heating fan control   
Four way valve (ST1)  ON   
Electronic expansion valve (EXV A)  Heating EXV control   
Electronic expansion valve (EXV B)  Heating EXV control   
Electronic expansion valve (EXV C)  0P   
Solenoid valve (SV4) 
17 min OFF,3min ON 
 
Solenoid valve (SV7) 
Pc ≥ 507.6 psi ON,Pc < 420.6 psi OFF 
 
NOTE: Heating operation is not functional at an outdoor air temperature of 77°F or more. 
b.  Capacity Calculation 
Table 6 - Cooling Calculation 
Indoor Unit 
Capacity (BTU) 
Indoor Unit 
Capacity x 100W 
Indoor Unit 
Capacity (HP) A 
Indoor Unit Capacity 
(BTU) 
Indoor Unit Capacity 
x 100W 
Indoor Unit Capacity 
(HP) A 
6000  15, 17  0.5  36000  112  4.0 
7000  22, 25  0.8  42000  125  4.5 
9000  28  1.0  48000  140  5.0 
12000  32, 36  1.2  54000  160  6.0 
13000  40  1.4  60000  180  6.5 
15000  45, 50  1.7  66000  200  7.0 
18000  56  2.0  72000  224, 252  8.0 
21000  63  2.2  96000  280  10.0 
24000  71  2.5  120000  335  12.0 
27000  80  3.0  144000  400  14.0 
30000  90  3.2  168000  450  16.0 
33000  100  3.6  192000  560, 580  20.0 
22