Panasonic 2WAY Multi - P20 Refrigerant High-Pressure Error

IV–96
P20 Refrigerant High-Pressure Error
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Error detection method
• When the high pressure sensor value ≥ 3.75 MPa during engine operation, the engine stops and an error fl ag
is set. A Refrigerant Pressure Too High fault is assumed when this fl ag has stopped the engine 5 consecutive
times in 1 hour.
• When revolution speed setting is more than minimum revolution speed and fan frequency is less than 50% of
maximum frequency, an error is not generated. (The engine stops momentarily.)
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Troubleshooting
1
Cooling/
heating
mode
1-1 Operating in the cooling mode or heating mode?
Cooling 2-1
Heating 3-1
2
Outdoor
unit’s heat
exchanger
check
2-1
Is the heat exchanger clogged by foreign matter or other
debris (visual inspection)?
Yes Remove
No 2-2
2-2 Is there an air shortage?
Yes
Revise
installation
No 2-3
2-3 Is the fan on the outdoor unit operating?
Yes 12-1
No
Refer to section
P22
3
Tubing 3-1
Are there any crushed tubes, torn strainers, closed servicing
valves, or other problems? Check the temperature of the
indoor unit’s coil.
Yes Repair
No 4-1
4
Unit check
4-1
Which is connected, an indoor unit or a water heat exchanger
unit?
Proceed to 5-1 when the
indoor unit is connected
Proceed to 8-1 when the
water heat exchanger unit is
connected
5
Indoor
unit’s heat
exchanger
check
5-1 Is the air fi lter on the indoor unit clogged?
Yes Clean the fi lter
No 5-2
5-2 Is the fan on the indoor unit operating?
Yes 6-1
No Repair
6
Indoor unit’s
motor-
operated
valve check
6-1
Check the indoor unit’s motor-operated valve. Does the valve
open? (Check the indoor unit’s heat exchanger temperature
when in the heating mode.)
Yes 7-1
No 6-2
6-2
Check the indoor unit’s control board. (Is there any voltage
between No. 5 (+) and No. 1-4 (-) of the indoor unit’s control
board PMV6P (white) CN082 when the power is switched on?)
Yes 6- 3
No
Replace the
indoor unit’s
control board
6-3
Check the motor-operated valve coil. (Does a resistance of
approximately 46 Ω exist between No. 5 and No. 1-4 of the
motor-operated valve connector 5P (white)* or 6P (white)?)
Yes
Replace the
valve
No
Replace the
valve coil
7
Indoor unit’s
coil sensor
7-1
Are indoor unit’s coil sensors E1, E2, and E3 disconnected
from their measurement points? Check this by displaying the
indoor coil temperature on the outdoor unit.
Yes Repair
No 11-1
8
Cold/hot
water check
8-1
Is a correct cold/hot water (brine) fl ow volume being
maintained?
Yes
Maintain the
rated fl ow volume
No 8-2
8-2 Is the cold/hot water (brine) pump operating?
Yes 9-1
No Repair
GHPtroubleshooting.indbIV‒96GHPtroubleshooting.indbIV‒96 2012/11/2611:20:142012/11/2611:20:14