Midea MS11D-24HRDN1 / MO11D-24HRDN1 [38/56] Main protection

Neola Inverter DM13-01.01.12 en

38 Service manual

10.3 Main Protection

10.3.1 Three Minutes Delay at restart for compressor

1 minute delay for the 1

time start-up and 3 minutes delay for others.

10.3.2 Temperature protection of compressor top

The unit will stop working when the compressor top temp. protector cut off, and will restart after the

compressor top temp. protector restart.

10.3.3 Temperature protection of compressor discharge

When the compressor discharge temp. is getting higher, the running frequency will be limited as below

rules:

---Compressor discharge temp. T5>115 for 5s, compressor stops.

---108<T5<115, decrease the frequency to the lower level every 3 minutes.

---90<T5<105, keep running at the current frequency.

----T5<90, no limit for frequency.

10.3.4 Fan Speed is out of control

When Indoor Fan Speed keeps too low (300RPM) for certain time, the unit will stop and the LED will

display the failure

10.3.5 Inverter module Protection

The Inverter module has a protection function about current, voltage and temperature. If these

protections happen, the corresponding code will display on indoor unit and the unit will stop working.

10.3.6 Indoor fan delayed open function

When the unit starts up, the louver will be active immediately and the indoor fan will open 10s later.

If the unit runs in heating mode, the indoor fan will be also controlled by anti-cold wind function.

10.3.7 Compressor preheating functions

Preheating permitting condition:

If T4(outdoor ambient temperature)＜3 and the machine connects to power supply newly or if T4＜3

and compressor has stopped for over 3 hours, the compressor heating cable will work.

Preheating mode:

A weak current flow through the coil of compressor from the wiring terminal of the compressor, then the

compressor is heated without operation.

Preheating release condition: