Mitsubishi Electric Lossnay LGH-50RVS-E Handbook page 28

(4) Failure mode 4: Error code and LED display
An error code displayed on the remote controller (PZ-62DR-E, PZ-43SMF-E) or the M-NET controller, and
blinking or illumination of LED1 (green) or LED2 (red) on the circuit board show the type of an error.
The LED blink interval is 0.25 seconds for both on and off. The display duration is approximately 7 seconds.
Error display list
Error LED1 LED2
Code (green) (red)
0900
3126 8
blinks
0.25 s 0.25 s 0.25 s
ON
OFF
Error display example: Two blinks
Symptom
Trial operation The trial operation switch (SW2-1)
on the circuit board is set to "ON".
External When the terminals (TM3 [9] [10])
device error or Lossnay signal output terminal
PZ-4GS-E are set for pre-heater
output (the function setting No. 12
of PZ-62DR-E is set to "6", and No.
13 to 16 are set to "5"), the following
conditions were satisfied.
• Outdoor air temperature detected
by OA thermistor stays at 70°C or
higher for one minute.
• Outdoor air temperature detected
by OA thermistor exceeds 15°C
within 15 minutes after the pre-
heater output starts.
• Outdoor air temperature is still
-10°C or lower 5 minutes after the
pre-heater output starts.
Causes of the above phenomenons
are described below.
The pre-heater is connected to the
wrong terminal.
Faulty connection of the pre-heater
The output capacity of the pre-heater
is too large with respect to the air
volume of the Lossnay unit.
The output capacity of the pre-heater
is too small with respect to the air
volume of the Lossnay unit.
Pre-heater failure
Pre-heater relay failure
Circuit board failure
7 s
Cause
─ 28 ─
Corrective action
Check the trial operation switch.
(See the Lossnay Operating/
Installation Instructions or
PZ-62DR-E Instruction Book.)
See below.
Connect the pre-heater to the ter-
minals (TM3 [9] [10]).
(See the Lossnay Operating/
Installation Instructions or
PZ-62DR-E Instruction Book.)
Check the pre-heater connections.
Adjust the output capacity of the
pre-heater. When the pre-heater is
used, run the Lossnay at a higher
fan speed.
Adjust the output capacity of the
pre-heater. When the pre-heater is
used, run the Lossnay at a lower
fan speed.
Replace the pre-heater.
Replace the relay for the pre-heater.
First, replace the control circuit
board.
If the problem persists, then
replace the power circuit board.