38
Phenomena
Factor
Countermeasure
7. Remote controller display works nor-
mally and the unit performs heating
operation, however, the capacity
cannot be fully obtained.
1
Linear expansion valve fault
Opening cannot be adjusted well due to linear expan-
sion valve fault.
2
Refrigerant shortage
3
Lack of insulation for refrigerant piping
4
Filter clogging
5
Heat exchanger clogging
6
Air duct short cycle
7
Bypass circuit of outdoor unit fault
1
• Discharging temperature and indoor
heat exchanger temperature does not
rise.
Inspect the failure by checking discharg-
ing pressure.
• Replace linear expansion valve.
2
• If refrigerant leaks, discharging tempera
ture rises and LEV opening increases.
Inspect leakage by checking the tem-
perature and opening.
• Check pipe connections for gas leakage.
3
Check the insulation.
4
Open suction grill and check the filter.
Clean the filter by removing dirt or dust on
it.
5
• If the filter is clogged, indoor pipe tem-
perature rises and discharging pressure
increases. Check if heat exchanger is
clogged by inspecting discharging pres-
sure.
• Clean the heat exchanger.
6
Remove the shield.
7
Check refrigerant system during operation.
8.
1
For 3 minutes after temperature
adjuster turns off, the compressor
will not start operating even if
temperature adjuster is turned on.
2
For 3 minutes after temperature
adjuster turns on, the compressor
will not stop operating even if
temperature adjuster is turned off.
(Compressor stops operating
immediately when turning off by
the remote controller.)
12
Normal operation
(For protection of compressor)
12
Normal operation
5. When operating by the wireless
remote controller, beep sound is
heard, however, unit does not start
operating.
1
No operation for 2 minutes at most after the power
supply ON.
2
Hand-held remote controller operation is prohibited.
• Remote controlling adaptor is connected to CN32
on the indoor controller circuit board.
• Hand-held remote controller operation is prohibited
by centralised controller etc. since it is connected to
MELANS.
3
Factor of No.2 on the previous page.
1
Normal operation.
2
Normal operation.
3
Check the details of No.2 on the previous page.
6. Remote controller display works
normally and the unit performs
cooling operation, however, the
capacity cannot be fully obtained.
(The air does not cool well.)
1
Refrigerant shortage
2
Filter clogging
3
Heat exchanger clogging
4
Air duct short cycle
1
• If refrigerant leaks, discharging tempera-
ture rises and LEV opening increases.
Inspect leakage by checking the tem-
perature and opening.
• Check pipe connections for gas leakage.
2
Open suction grill and check the filter.
Clean the filter by removing dirt or dust on
it.
3
• If the filter is clogged, indoor pipe tem-
perature rises and discharging pressure
increases. Check if heat exchanger is
clogged by inspecting discharging pres-
sure.
• Clean the heat exchanger.
4
Remove the shield.
9. Defective fan of outdoor units.
(Not rotate)
1
Check the winding resistance.
Refer to 12-6.
However, make sure to check the resis-
tance after it gets cold enough (
[
87
i
15
:
),
as there is a possibility that the tempera-
ture protector housed in the fan motor is
working.
2
Check CN2, CN5, CN6, TAB-U, TAB-V,
TAB-W, TAB-W wiring.
3
Replace outdoor fan controller circuit board.
1
Defective fan motor (Winding open or shoot)
2
Disconnection or loose connection of connector on
outdoor Fan controller circuit board
3
Defective outdoor fan controller circuit board
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