Control Specification
SiBE041025
26
Function and Control
2.4
Controls at Mode Changing / Start-up
2.4.1 Preheating Operation
Outline
The inverter operation in open phase starts with the conditions of the preheating command from
the indoor unit, the outdoor temperature, and the discharge pipe temperature.
Detail
ON Condition
When the discharge pipe temperature is below 10ºC, the inverter operation in open phase
starts.
OFF Condition
When the discharge pipe temperature is higher than 12ºC, the inverter operation in open
phase stops.
2.4.2 Four Way Valve Switching
Outline
In heating operation, current is conducted, and in cooling and defrosting, current is not
conducted. In order to eliminate the switching sound when the heating is stopped, as the four
way valve coil switches from ON to OFF, the OFF delay switch of the four way valve is carried
out after the operation stopped.
Detail
OFF delay switch of four way valve:
The four way valve coil is energized for 160 seconds after the operation is stopped.
2.4.3 Four Way Valve Operation Compensation
Outline
At the beginning of the operation as the four way valve is switched, the differential pressure to
activate the four way valve is acquired by having output frequency which is more than a certain
fixed frequency, for a certain fixed time.
Detail
Starting Conditions
1. When starting compressor for heating.
2. When the operation mode changes to cooling from heating.
3. When starting compressor for defrosting or resetting.
4. When starting compressor for the first time after the reset with the power is ON.
5. When starting compressor for heating next to the suspension of defrosting.
6. When starting compressor next to the fault of switching over cooling / heating.
Set the lower limit frequency
Hz for
seconds with any conditions 1 through 6 above.
(Hz)
62
(seconds)
50
