Midea MSV1-09HRDN1, Service Manual

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Service manual
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11.2. Protection
11.2.1. 3 minutes delay at restart for compressor.
11.2.2. Temperature protection of compressor top, compressor stops when the temp. of top of
compressor is more than 115
℃
, compressor runs when the temp. of top of compressor is less than
100 ℃ .
11.2.3. Voltage protection, unit stop when the voltage is more than 260V and less than 175V.
11.2.4. Inverter module Protection, Inverter module Protection itself has a protection function against
current, voltage and temperature.
11.2.5. Sensor protection at open circuit and breaking disconnection
11.2.6. Fan Speed is out of control. When Indoor Fan Speed is too high (higher than 2100RPM) or too
low (lower than 300RPM), the unit stops and LED displays failure information and can’t return to
normal operation automatically.
11.2.7. Cross Zero signal error warning. If there is no Cross Zero signals in 4 minutes, the unit stops
and LED displays failure information and can’t return to normal operation automatically.
11.3. Fan-only mode
Fan speed is high/mid/low/ Auto
11.4. Cooling mode
11.4.1. The 4-way valve is closed at cooling mode.
11.4.2. The action of the compressor and the outdoor fan:
Condition
T=Indoor Temp.
Compressor Outdoor fan
T> Ts+1 On On Room temp. up
T<Ts+1 Off Off
T> Ts On On Room temp. down
T<Ts Off Off
11.4.3 Auto fan at cooling mode:
Condition
T=Indoor Temp.-Setting Temp.
Indoor fan speed
T<1.5 ℃ Low
1.5
℃
<T<4
℃
Mid.
Room temp. up
T>4
℃
High
T> 3
℃
High
1 ℃ <T<3 ℃ Mid.
Room temp. down
T<1
℃
Low
11.4.4 Anti-freezing control to indoor evaporator at cooling mode( T: evaporator temp. )
Evaporator Temp. Compressor
0
℃
<T< 4
℃
Decrease frequency of compressor
T< 0
℃
Off
11.4.5 Current protection
Model Current Compressor
I>18 A Off
14.5A<I<18A Decrease frequency of
compressor
Current up MSH-18HRIN1
I< 12.0A On
I>17.5 A Off
14.0A<I<17.5A Decrease frequency of
compressor
Current down MSH-18HRIN1
I< 11.5A On
11.4.6 Rated capacity test
Set mode to cooling mode