Invest MSC-24/QD FP, Service Manual

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20
T1 – 24
8.2.2 LED display control function.
Pressing “LED display” button on remote controller will turn off all displays on indoor unit, while pressing once again,
all displays will resume.
8.3 Protection
8.3.1 Protection of compressor top temperature.
When the Over-load Protector is cut due to too high temperature of compressor top, the unit will stop.
When the Over-load Protector is closed again due to decreasing of compressor top temperature, the unit will
restart( in this case the compressor is restricted by Three Minutes Delay protection).
8.3.2 Protection of discharge temperature (Td).
1) Compressor will stop immediately if Td>115 for 5s.
2) If 90 ≤ Td ≤ 115 , compressor will run with restricted frequency.
3) If Td<90 , compressor will restart or run without restricted frequency
8.3.3 Three Minutes Delay at restart for compressor.
It will take 3 minutes every time when compressor starts.
It will take only 1 minute when the unit is powered on at first time.
8.3.4 Temperature sensor protection at open circuit or short circuit.
8.3.5 Inverter module Protection.
Inverter module has a protection function against current, voltage and temperature. If these protections
happened, the unit will stop and LED display error code .
8.3.6 Indoor fan delayed open function.
When the unit is turned on at all modes, the indoor fan will operate 10 seconds later than the action of
louver.
8.3.7 Compressor preheating function.
1) 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.
2) Preheating mode:
A weak current flows through the coil of compressor from the wiring terminal of compressor, then
the
compressor is heated without operation.
3) Preheating release condition:
If T4 5 or user turns on the machine and compressor runs, preheating function will stop.
8.3.8 Compressor heating cable
If outdoor temperature is lower than 5 , the compressor heating cable begins to work. If outdoor
temperature is higher than 15 , the compressor heating cable stops working.
8.4 Fan-Only Mode
8.4.1 Temperature setting function is disabled, and no setting temperature display.
8.4.2 In this mode, the action of louver is the same as in cooling mode.
8.4.3 The action of auto fan in fan-only mode is the same as auto fan in cooling mode with 24 setting
temperature.
medium
3.5
3.0
high
1.5
1.0 low