Mitsubishi FDC 6 Series User Manual

28
52C secondary side
L2 or L3 phase open?
Repair
YES
NO
Defective outdoor unit PCB
Replacement
(Defective CT circuit)
(1)
(2)
Outdoor unit
Red LED
Green LED
3 time flashes
Stays OFF
Is L3 phase at
primary side at open
phase
Correction
YES
NO
Defective outdoor unit PCB
Replacement
Outdoor unit
Red LED
Green LED
1 time flash
Stays OFF
NO
Power supply
checked at L 1 - L 2 , L 1 - L 3
or L 2 - L 3 phase of 52C
secondary side?
YES
YES
Compressor
overcurrent?
NO
Inspect at the unit side.
(1)
• Is the power supply voltage correct
(not too low)?
• Are the power supply wires appro-
priate (not too thin)?
• Is the overcurrent setting correct
(SW3 setting)?
• Is not it operated under overload?
Defective outdoor unit PCB
Replacement (Defective
CT input circuit)
• 3 Phase: Open phase at L 1
or L 2 phase
• Defective 52C
• 3 phase: Broken wire at L 1 or L 2
phase between 52C ~ CM or
TB 1 ~ 52C
• During cooling: Is FM 0 operating?
• At heating:
Is FM 1 operating?
Is the service valve (gas side) opened
fully?
Is the filter clogged?
• Is it overcharged?
• Is the installation space of indoor
outdoor unit adequate?
• Is there any short circuit on the indoor/
outdoor unit?
2
Overcurrent of the compressor motor
Note (1) Measure and check the current value.
Confirm that the overcurrent setting by SW
3 of outdoor
unit PCB is correct.
Outdoor unit
Red LED
Green LED
2 time flashes
Stays OFF
3
The wiring (secondary wiring of 52C) to the compressor is open.
Notes (1) When voltage is detected at 52C primary side
L2
or
L3
phase but not at the secondary side, check also 52C (bro-
ken coil, poor contact).
(2) When voltage is detected at 52C primary side
L2
or
L3
phase and there is no error at 52C (52C is energized if TB
1
L2
or
L3
terminal and 52C coil secondary side connector
are short circuited), the outdoor unit PCB (defective X
01
circuit or X
01
) or indoor unit PCB (defective thermostat
circuit) is defective.
(b) Inspection method when there are fault lamps (outdoor unit LED)
1
Open phase at L3 phase (Primary side)

Mitsubishi FDC 6 Series Specifications

General

Brand	Mitsubishi
Model	FDC 6 Series
Category	Air Conditioner
Language	English