Panasonic S-22ML1E5, Service Manual & Test Run Service Manual

Page: 21 / 175

1 - 11
Mini VRF SYSTEM
Control Functions - Outdoor unit
1
3. Output of PCB 4. Special Control
2WAY VRF SYSTEM
Control Functions
Items Remarks Indication on PCB
This valve turns OFF at cooling mode, and turns ON at heating mode.
When the outdoor unit stops, the 4-way valve maintains in the same state as before.
Regarding the operation in defrost control, see the section “8. Defrost Control”.
Solenoid valve
Motor Operated Valve
Crankcase heater
4-way valve
Oil recovery valve
O
2
valve
MOV for heat exchanger
MOV for Sub cooler
Crankcase heater
20S
ORVR
O
2
MOV1
MOV4
CH
(1) 4-way Valve [20S]
This valve turns ON for 5 seconds before the inverter compressor starts. After the inverter compressor starts, the
valve is ON for 2 minutes. After that, it turns OFF.
ORVR valve
5 seconds 2 minutes
Inverter compressor starts
Compressor
Valve turns ON Valve turns OFF
This valve turns ON for 30 seconds after the outdoor unit stops. After that, it turns OFF.
This valve turns ON when the high pressure is too high.
This valve turns OFF when the high pressure goes down.
This valve turns ON when the high pressure switch is activated.
This valve stays ON for 10 seconds after the high pressure switch returns in normal.
After that, it turns OFF.
This valve might turn ON when the system capacity is excessive although the inverter compressor operates at
minimum frequency.
This valve turns ON while the discharge temperature of the compressor is low.
This valve turns ON during the operation of 4-way valve control.
(2) Oil Recovery Valve [ORVR]
The purpose of this valve is to recover oil from the oil separator to the compressor and is to adjust the
capacity and pressure.
This valve is always OFF when outdoor unit is stopped.
2WAY VRF SYSTEM
Control Functions
4. Special Control
(3) O
2
Valve [O
2
] *O
2
valve is the local supply parts.
This valve works when the outdoor unit receives signal of the refrigerant leakage from the indoor unit.
(5) Crankcase Heater Control [CH]
When the compressor stops, the crankcase heater of its own compressor is turned ON / OFF in the following
conditions.
●
When the outdoor air temperature < 25°C :ON
●
When the outdoor air temperature ≥ 27°C : OFF
The indoor unit that transmits the signal of the refrigerant leakage gives “P14”alarm.
To activate this function, it is necessary to set it to EEPROM on the main outdoor PCB and indoor PCB.
EEPROM setting in main outdoor unit
CODE: C1
Setting No.
Setting No.
0
0
1
1
2
This function invalid (factory preset mode)
3 Never use
This valve is turned OFF when the system is normal.
This valve is turned ON when the outdoor unit receives signal from the indoor unit
This valve is turned ON when the system is normal.
This valve is turned OFF when the outdoor unit receives signal from the indoor unit
EEPROM setting in indoor unit
CODE: 0B
Function of EXCT plug short-circuit
Indoor unit does thermostat OFF
(factory preset mode)
Indoor unit gives “P14”alarm and transmits the refrigerant leakage signal.
4-1. Type of Electronic control valves
4-2. Power Initialization
MOV1 is for adjusting refrigerant flow amount of outdoor heat exchanger.
MOV4 is for adjusting refrigerant flow amount of Sub cooler.
If no indoor units have started (even once) after the power supply to the outdoor unit, the MOV holds the 480
pulses (fully open).
4-3. Control of Electronic control valves
Electronic control valves for heat exchanger control according to the operation mode.
Cooling Heating Mode of system
Compressor
MOV1 and MOV4 (pulse)
Stop
Stop
0
Operation
480
Stop
0*
1
Operation
0 ~ 480*
3
Stop
0*
2
* When the indoor unit receives the signal for operation request from the control equipment, the pulse turns
other than the 480 pulses (regardless of the thermostat ON/OFF or operating ON/OFF).
It is necessary to switch ON the power supply again if the 480 pulses are required.
*1 However, 100 pulses remain for 2 minutes after unit stopped.
*2 When the outdoor unit stops and low pressure ≤ 0.16 MPa, 100 pulses remain for 30 seconds.
*3 If the outdoor unit is operating in heating mode, electronic control valves perform SH control.
SH control adjusts the difference of temperature between the liquid and gas temperature to -1 ~ 5 degrees
Celsius.
(4) Electronic Control Valves [MOV1, MOV4]
SM830258-01_欧州向け_1fan_mini_VRF.indb 11 18/03/06 9:09:49