Daikin FXYBP20K7V1, Service Manual

Page: 175 / 193

Troubleshooting (Inverter) SiE 00-07
164 Troubleshooting R-407C PLUS Series
5.6 Power Supply Insufficient or Instantaneous Failure
Remote Controller
Display
U2
Supposed Causes Power supply insufficient
Instantaneous failure
Open phase
Defect of inverter unit
Defect of outdoor PC board
Defect of K1M.
Main circuit wiring defect
Troubleshooting
(VF068)
Replace K1M.
NO
Turn on again.
Replace the outdoor unit
PC board.
YES
Turn K1M ON.
YES
NO
Is 220 ~ 240 V of power
reaching the K1M
coil?
Is 220 ~ 240 V at
the connector of X1A.
Replace the inverter unit.
Replace the inverter unit.
YES
NO
NO
Does
the voltage
between terminals P
and N gradually rise to 339
VDC (Y1) after turning
on?
"U2" blinks again.
Monitor field power supply.
The voltage
between the P and N
terminals is 320 VDC (Y1)
or morewhen the
compressor
is running.
YES
NO
Is 220 ~ 240 V
at the connector of X5Aof
outdoor PC board
side?
Check
the transmission
wiring between the outdoor
unit PC board and
inverter unit.
YES