Controls At Mode Changing / Start-Up - Daikin SiBE04-624_B_FTXR-E Service Manual

Control Specification
2.2

Controls at Mode Changing / Start-up

2.2.1 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.
Outdoor temperature ≥ 7°C
Detail
Outdoor temperature < 7°C
2.2.2 Four Way Valve Switching
Outline In heating operation, current is conducted, and in cooling and defrost operation, current is not
conducted. In order to eliminate the switching sound, as the four way valve coil switches from
ON to OFF when the heating is stopped, the OFF delay switch of the four way valve is carried
out.
Detail OFF delay switch of four way valve:
The four way valve coil is energized for 160 seconds after the operation is stopped.
2.2.3 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 the compressor starts and the four way valve switches from OFF to ON
2. When the four way valve switches from ON to OFF during operation
3. When the compressor starts after resetting
4. When the compressor starts after the fault of four way valve switching
The lower limit of frequency keeps A Hz for B seconds with any conditions 1 through 4 above.
Condition
Cooling
Heating
56
Discharge pipe temperature
10˚C
Discharge pipe temperature
20˚C
outdoor temperature < 16°C
outdoor temperature ≥ 16°C
Preheating OFF
12˚C
Preheating ON
Preheating OFF
Preheating ON
A (Hz)
52
52
– 0.9 × outdoor temperature + 68
SiBE04-624_B
(R5922)
22˚C
(R5923)
B (seconds)
60
Function and Control