Mitsubishi Electric PUH-P8YE Technical & Service Manual page 46

Abnormal- Meaning of abnormality display and
ity display abnormality troubleshooting
Low pressure abnormal (63L trip)
Detected by tripping of 63L while the
compressor is operating. (Ignored
UL during defrosting and for 10 minutes
at defrosting return.)
63L: Pressure switch (low pressure)
OFF: 0 MPa
Remote controller communica-
tions receive abnormal (remote
controller).
1) When transmission from refriger-
ant address "0" IC is not received
EO normally even once in 3 minutes,
an abnormality is recognized.
2) When a slave remote controller
does not receive even one signal
in 2 minutes, an abnormality is
recognized.
Remote controller communication
send abnormal (remote controller)
1) When the remote controller can
not confirm that the transmission
circuit is idle in 6 seconds, an ab-
E3
normality is recognized.
2) When the remote controller can-
not complete 30 continuous trans-
missions, an abnormality is rec-
ognized.
Indoor-outdoor communication
receive abnormal
(Outdoor unit)
When the outdoor controller can
E8
not receive normally even once in
3 minutes, an abnormality is rec-
ognized.
Indoor-outdoor communication
send abnormal
(Outdoor unit)
1) When the outdoor controller
detectes reception of 30 consecu-
tive "0" even through "1" was re-
E9
ceived, an abnormality is recog-
nized.
2) When the outdoor controller can
not confirm that the transmission
circuit is idle in 3 minutes, an er-
ror is recognized.
Check code undefined
Displayed when an undefined check
EF code is received.
Cause
1 Started with ball valve closed.
2 Connector (CN27) on outdoor control-
ler board open or contact faulty.
3 63L disconnected or contact faulty.
4 Part faulty.
1 Remote controller send/receive
circuit faulty.
2 Refrigerant address "0" indoor control-
ler board send/receive circuit faulty.
3 Noise entered on remote controller
transmission line.
1 Remote controller send/receive circuit
faulty.
2 Noise entered on remote controller
transmission line.
1 Indoor/outdoor connection wire contact
faulty.
2 Outdoor controller board send/receive
circuit faulty.
3 Indoor controller board send/receive
circuit faulty.
4 Noise entered on indoor/outdoor con-
nection wire.
1 Outdoor controller board send/receive
circuit faulty.
2 Noise entered at power supply.
3 Noise entered on indoor/outdoor con-
nection wire.
1 Noise entered on remote controller
transmission line.
2 Noise entered on indoor/outdoor con-
nection wire.
–44–
Judgment method and remedy
1 Check if ball valve fully open.
2 3 Repair connector.
4 Replace pressure switch.
Perform remote controller diagnosis.
Take the following action based on the di-
agnosed result:
a) [RC OK] display
Remote controller normal.
Turn power off and on and check.
If "H0" remains on for 4 minutes or
longer, replace indoor controller board.
b) [RC NG] display
Replace remote controller.
c) [RC E3] display Noise, etc. probable
[ERC00-66] cause.
1 Check for disconnected or loose indoor
unit or outdoor unit indoor/outdoor con-
nection wire.
2-4
Turn power off and on and check.
If abnormality displayed again, replace
indoor controller board or outdoor con-
troller board.
123
Turn power off and on and check.
If abnormality displayed again, replace
indoor controller board or outdoor con-
troller board.
12
Turn power off and on and check.
If abnormality displayed again, replace
indoor controller board or outdoor con-
troller board.