Mitsubishi Electric LGH-F300RVX2-E Handbook page 35

Error LED1 LED2
Code (green) (red)
5102 5 Return air
blinks (RA) thermis-
tor related
error
5501 12 CO
blinks error (Optional
components:
PZ-70CSW-E,
PZ-70CSB-E)
6201 PZ-62DR-EA
circuit board
failure
6202 PZ-62DR-EA
circuit board
failure
6600 6 Multiple
blinks address error
(*3) This refers to devices assigned an address number in MELANS such as the Lossnay unit, City Multi indoor
unit, City Multi outdoor unit, or system controller.
Symptom
Faulty connection of the thermistor
connector (CN5) on the control cir-
cuit board
Thermistor failure
sensor The connectors for the CO
2
are disconnected.
CO sensor failure
2
Even though the CO
connected, CO
function selection switches (SW5-6
to SW5-8) on the circuit board or
the function setting (No. 66) of
PZ-62DR-EA) is set as shown below.
• "PZ-70CSW-E connected" (SW5-6: ON,
SW5-7 and SW5-8: OFF, or No.66: 5)
• "PZ-70CSB-E connected" (SW5-6 and
SW5-7: ON, SW5-8: OFF, or No.66: 7)
Remote controller failure
Clock function of the remote control-
ler is not working properly.
The system contains two or more
units (*3) with the same address in
the same M-NET transmission cable
line.
Cause
sensor
2
sensor is not
2
sensor setting (the
2
─ 35 ─
Corrective action
Check the connector (CN5)
connection.
Disconnect the connector (CN5),
and check the resistance of the
thermistor.
If the equivalent thermistor resis-
tance differs greatly from the
ambient temperatures, replace the
thermistor. (See (5) Temperatures
and thermistor resistance table
(page 39).)
Check the connector connections
(CN34 (only for PZ-70CSW-E),
CN23, CN26, and CN35) on the
control circuit board.
Check the CO sensor wiring
2
according to the PZ-70CSW-E/
PZ-70CSB-E Installation and
Instruction Manual. If the problem
persists even after correcting the
wiring, replace the CO
2
When the CO sensor is not con-
2
nected, set the function selection
switches (SW5-6 to SW5-8) on the
circuit board to OFF, or the function
setting (No. 66) of PZ-62DR-EA to
"1: No external fan speed control
input".
Replace the PZ-62DR-EA remote
controller.
Replace the PZ-62DR-EA remote
controller.
Find the units (*3) with the same
address, and set unique addresses
to these units.
sensor.