Controls At Mode Changing / Start-Up - Daikin 2MXS40H2V1B Service Manual

SiBE121123_A
4.3

Controls at Mode Changing / Start-up

4.3.1 Preheating Control
Outline The inverter operation in open phase starts with the conditions of the outdoor temperature and
the discharge pipe temperature.
Detail ON Condition
OFF Condition
4.3.2 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, 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 after the operation stopped.
Detail OFF delay switch of four way valve:
The four way valve coil is energized for 150 seconds after the operation is stopped.
4.3.3 Four Way Valve Operation Compensation
Outline At the beginning of the operation as the four way valve is switched, the pressure difference 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 60 seconds with any conditions 1 through 4 above.
4.3.4 3-Minute Standby
Turning on the compressor is prohibited for 3 minutes after turning off.
(Except when defrosting.)
Function and Control
When outdoor temperature is below 10.5°C and discharge pipe temperature is below
10.5°C, the inverter operation in open phase starts.
When outdoor temperature is higher than 12°C or discharge pipe temperature is higher than
12°C, the inverter operation in open phase stops.
Cooling
A
(Hz)
Heating
40 class 50 class
56 40
68 54
Control Specification
94