Midea AAC-18ISCH, Service Manual

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Service manual
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11.7. Defrosting operation (Available for heating only).
11.7.1 Defrosting condition:
11.7.1.1. When outdoor temp. is more than 0
℃
,
Defrosting starts when meeting one of the following conditions,
a. The temperature of outdoor heat exchanger remains consecutively lower than 3°c for more
than 40 minutes, and the temperature remains consecutively -4°c for more than 3 minutes,
b. The temperature of outdoor heat exchanger remains consecutively lower than 3°c for more
than 80 minutes, and the temperature remains consecutively -2°c for more than 3 minutes
11.7.1.2. When outdoor temp. is less than 0
℃
,
Defrosting starts when meeting one of the following conditions,
a. The temperature of outdoor heat exchanger remains consecutively lower than 3°c for more
than 40 minutes, and the temperature remains consecutively -6°c for more than 3 minutes,
b. The temperature of outdoor heat exchanger remains consecutively lower than 3°c for more
than 40 minutes, and the temperature remains consecutively -6°c for more than 3 minutes,
c. The temperature of indoor unit pipe decreases 5°c than before
11.7.1.3.
The temperature of outdoor heat exchanger remains consecutively lower than 3°c for more
than 120 minutes, and the temperature remains consecutively -2°c for more than 3 minute
s
11.7.2 Ending condition of defrosting
If one of following conditions is satisfied, end the defrost and turn into heating mode:
a. The defrost time has reached to 10 minutes.
b. When the temperature of outdoor heat exchanger rises up to 8°C and this continues for more than 80
seconds.
c. When the temperature of outdoor heat exchanger rises up to 12°C
11.7.3 Defrosting Actions:
11.7.4 Rated capacity test
Set mode to cooling mode
Set temp. to 30 °C
Set fan speed to high speed
Push turbo button 5 times in 10 seconds.
Using special remoter controller
After 5 hours, cancel rated capacity test
11.8. Outdoor low temperature protection (optional)
Factory standard unit has not this function.
Unit stops when outdoor temp. is low than -15°C and lasting time more than 60 minutes, and unit runs
again when outdoor temp. more than -12°C.
When indoor PCB J1 jump is on, this function is available.
11.9. Automatic operation mode
The air conditioner automatically selects one of the following operation modes: cooling, heating or fan
max. 10 minutes
60s
ON 10s 30s
Com. OFF
ON ON
4 way valve OFF
ON ON
Outdoor fan OFF
ON ON
Indoor fan
OFF
Breeze 10 seconds, then stop