Panasonic U-4LE1R8 Service Manual page 69

3. Mini VRF System Alarm Codes
F16 High Pressure Sensor Error
1. Error Detection Method
It is judged an error based on the criteria listed below.
Cooling: Status of lower 5°C saturated temperature under the detect pressure compared to the outdoor heat exchanger
•
liquid temperature (C1 temp.) was continuosly detected for 30 minutes.
• Heating: Status of lower 5°C saturated temperature under the detect pressure compared to the highest E1 temperature
in the indoor unit was continuously detected for 30 minutes.
•
Open circuit or Short circuit
2. Error Diagnosis
1 Sensor
1-1 Sensor connector is connected to control PC board properly.
Is sensor resistance value in normal?
Disconnect the connector and measure the resistance value
between each wire of sensor.
1-2
Correct reference values:
between 1-2: 8.5 ｋ ohm, 1-3: 1.0 ｋ ohm, 2-3: 8.5ｋ ohm
2 Operating
2-1 Forgot to open the service valve
status
2-2 Tends to have insufficient refrigerant charge in the system.
2-3 Are the tubes clogged?
The difference between the value of actual high pressure and
3 Control PC
that of detect pressure will roughly indicate as shown below.
board
Judgement criteria
3-1
When measuring the value of actual high pressure, connect
the measuring gauge to the high pressure outlet port and
measure it.
The detect pressure value is the pressure value indicated
by the monitoring software display.
At time of outdoor
temperature lower than 20
At time of outdoor
temperature higher than 20
Difference of roughly
over 0.2MPa
°C
Difference of roughly
over 0.4MPa
°C
3-29
Mini VRF SYSTEM
Trouble Diagnosis
Yes 1-2
No Reconnect and check
Yes 2-1
No Replace sensor
Yes Correct
No 2-2
Adjust the amount
Yes
of refrigerant
No 2-2
Yes Avoid clogging
No 3-1
Yes Replace sensor
No Replace control PC
board
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