SiBE041012_A
Control Specification
Function and Control
38
3.3.2 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 150 ~ 160 seconds after the operation is stopped.
3.3.3 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 from heating to cooling
3. When starting compressor for defrosting
4. When starting compressor for heating after defrosting
5. When starting compressor for the first time after resetting with the power ON
6. When starting compressor after the fault of switching over cooling / heating
The lower limit of frequency keeps
A
Hz for
B
seconds with any conditions 1 through 6 above.
3.3.4 3-minute Standby
Turning on the compressor is prohibited for 3 minutes after turning it off.
(Except when defrosting.)
3.3.5 Compressor Protection Function
When turning the compressor from OFF to ON, the upper limit of frequency is set as follows.
(The function is not activated when defrosting.)
25/35 class
50 class
Cooling
Heating
Cooling
Heating
A
(Hz)
68
66
48
48
B
(seconds)
45
70
25/35 class
50 class
A
(Hz)
48
55
B
(Hz)
64
70
C
(Hz)
88
85
D
(seconds)
240
120
E
(seconds)
360
200
F
(seconds)
180
470
(sec.)
Time
(R13528)
(Hz)
Frequency
C
B
D
E
F
A