Operation Modes And Functions - Toyotomi MTN A371DV Service Manual

8.3.6 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.
8.3.7 Compressor preheating functions
Preheating permitting condition:
If T4(outdoor ambient temperature)＜3
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:
If T4＞5 or the compressor starts running, the preheating function will stop.
8.3.8 Zero crossing detection error protection
If AC detects time interval is not correct for continuous 240s, the unit will stop and the LED will display
the failure. The correct zero crossing signal time interval should be between 6-13ms.

8.4 Operation Modes and Functions

8.4.1 Fan mode
(1) Outdoor fan and compressor stop.
(2) Temperature setting function is disabled, and no setting temperature is displayed.
(3) Indoor fan can be set to high/med/low/auto.
(4) The louver operates same as in cooling mode.
(5) Auto fan:
8.4.2 Cooling Mode
8.4.2.1 Compressor running rules
and the machine connects to power supply newly or if T4＜
27.5
High
27
Medium
25.5
25
Low
24