SiE 00-07
Troubleshooting
Troubleshooting R-407C PLUS Series
147
3.25
Low Pressure Drop Due to Refrigerant Shortage or Electronic Expansion
Valve Failure
Remote Controller
Display
U0
Supposed Causes
Out of gas or refrigerant system clogging (incorrect piping)
Defect of pressure sensor
Defect of outdoor unit PC board
Troubleshooting
(VF052)
The suction
pipe temperature minus
coil temperature is 20 ˚C
or higher.
Resistance
is normal when
measured with the suction
pipe thermistor (R4T) and
coil thermistor (R2T)
disconnected
from the outdoor
unit PC
board.
Out of gas or refrigerant system is
clogged. Requires check of
refrigerant system.
Replace the thermistor.
Replace the outdoor unit PC
board (A1P).
YES
NO
NO
Out of gas or refrigerant system is
clogged. Requires check of
refrigerant system.
Replace low outdoor unit PC
board.
YES
YES
NO
Cooling
Low pressure
is 1.0 kg/cm² (0.098 MPa) or
less.
The voltage
of X21A pins (2)
and (3) on both sides of
outdoor unit PC board (A1P) is
0.8 VDC or less.
(Pressure sensor
output
voltage)
NO
NO
YES
YES
Replace low pressure sensor.
Summary of Contents for FXYBP20K7V1
Page 1: ...System R 407C PLUS Series Service Manual SiE 00 07 ...
Page 11: ...Introduction SiE 00 07 x ...
Page 17: ...Product Outline SiE 00 07 6 General Information R 407C PLUS Series ...
Page 41: ...Specifications SiE 00 07 30 Specifications R 407C PLUS Series ...
Page 119: ...Test Operation SiE 00 07 108 Test Operation R 407C PLUS Series ...
Page 132: ...SiE 00 07 Troubleshooting by Remote Controller Troubleshooting R 407C PLUS Series 121 ...