Troubleshooting - Toshiba MMU-AP0057MH-E Installation Manual

▼ Periodic Maintenance
• For environmental conservation, it is strongly recommended that the indoor and outdoor units of the air
conditioner in use be cleaned and maintained regularly to ensure efficient operation of the air conditioner.
When the air conditioner is operated for a long time, periodic maintenance (once a year) is recommended.
Furthermore, regularly check the outdoor unit for rust and scratches, and remove them or apply rustproof
treatment, if necessary.
As a general rule, when an indoor unit is operated for 8 hours or more daily, clean the indoor unit and outdoor
unit at least once every 3 months. Ask a professional for this cleaning / maintenance work.
Such maintenance can extend the life of the product though it involves the owner's expense.
Failure to clean the indoor and outdoor units regularly will result in poor performance, freezing, water leakage,
and even compressor failure.
Inspection before maintenance
Following inspection must be carried out by a qualified installer or qualified service person.
Parts
Open the air intake grille to remove the bell mouth and the fan, and then check the heat exchanger
Heat exchanger*
if there is any clogging or damages.
Fan motor Check if any abnormal noise can be heard.
Fan Open the air intake grille and check the fan if there are any waggles, damages or adhesive dust.
Filter Open the air intake grille and check if there are any stains or breaks on the filter.
Remove the panel, the bell mouth and the drain pan, and then check if there is any clogging,
Drain pan*
abnormal smell or drain water pollution.
* Refer to the Service Manual for how to remove.
▼ Maintenance List
Part Unit
Heat exchanger Indoor / outdoor
Fan motor Indoor / outdoor
Filter Indoor
Fan Indoor
Air intake / discharge
Indoor / outdoor
grilles
Drain pan Indoor
Ornamental panel,
Indoor
louvres
Exterior Outdoor
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Inspection method
Check (visual / auditory) Maintenance
Wash the heat exchanger when it is
Dust / dirt clogging, scratches
clogged.
Take appropriate measures when
Sound
abnormal sound is generated.
• Wash the filter with water when it is
contaminated.
Dust / dirt, breakage
• Replace it when it is damaged.
• Vibration, balance • Replace the fan when vibration or
balance is terrible.
• Dust / dirt, appearance
• Brush or wash the fan when it is
contaminated.
Fix or replace them when they are
Dust / dirt, scratches
deformed or damaged.
Dust / dirt clogging, drain Clean the drain pan and check the
contamination downward slope for smooth drainage.
Wash them when they are contaminated
Dust / dirt, scratches
or apply repair coating.
• Rust, peeling of insulator
Apply repair coating.
• Peeling / lift of coat
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11

Troubleshooting

 Confirmation and check
When a problem occurred in the air conditioner, the
check code and indoor UNIT No. appear on the display
part of the remote controller.
The check code is only displayed during the operation.
If the display disappears, operate the air conditioner
according to the following "Confirmation of check code"
for confirmation.
Check code
Indoor UNIT No. in which
a problem occurred
 Confirmation of check code
When a problem occurred on the air conditioner, the
check code can be confirmed with the following
procedure. (The check code is stored in memory up to
4 check codes.)
The check code can be confirmed from both operating
status and stop status.
2
3
1
When and buttons are pushed
simultaneously for 4 seconds or more, the
following display appears.
If is displayed, the mode enters in the check
code mode.
• [01: Order of check code] is displayed in CODE
No..
• [Check code] is displayed in CHECK.
• [Indoor unit address in which a problem
occurred] is displayed in Unit No..
2
Every pushing of button used to set
temperature, the check code stored in
memory is displayed in order.
The numbers in CODE No. indicate CODE No.
[01] (latest)  [04] (oldest).
REQUIREMENT
Do not push button because all the check code of the
indoor unit will be deleted.
3
After confirmation, push
to the usual display.
1
button to return
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