Si-95
Functions
Functions Inverter K Series
25
1.11
BS Changeover Control
The solenoid valve of the BS unit is switched according to the indoor unit operating condition.
When the solenoid is operable, if the operating condition differs from the solenoid condition, the solenoid is
switched according to the above table.
However, the following conditions take precedence.
Condition 1
Normal operation
Oil return, defrost
Cooling
Condition 2
Heating
Condition 3
Condition 4
Oil return, defrost
Oil return, defrost complete
Discharge defrost
Discharge oil return
Suction defrost
Suction oil return
(VF006)
Condition
Indoor unit operating condition
Y3S
Y2S
Y1S
ON: Open
OFF: Closed
1
Cooling
Heating stop
∗
1
OFF
ON
OFF
2
Heating thermostat OFF
Heating thermostat ON
ON
OFF
∗
2
3
Discharge oil return
OFF
OFF
OFF
4
Suction oil return
Defrost
ON
ON
OFF
∗
1 : Condition 2 results in heating stop units when no unit in the system is in cooling operation.
∗
2 : Condition 1 results when a unit connected to the BS unit is in heating thermostat ON condition
during simultaneous cooling/heating operations.
SI-95.BOOK Page 25 Friday, March 31, 2000 10:59 AM