innovair Inverter FLEX24 DEV24H2R18, Service Manual

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and outdoor and indoor fan will both stop. When the temperature sensed by outdoor tube temperature sensor
reaches the preset value of defrosting stop, system will quit defrosting. The 4-way valve will switch back to the
heating condition, compressor and outdoor unit fan restart.
2.2.2.2 Oil Return Control
If the unit is running at low frequency for a long time, system will enable oil return control. This is to lead oil in
the pipeline back to the compressor so that the compressor will not be lack of oil. Generally, the oil return takes
about 5min. The compressor running frequency will be raised to the preset oil return frequency.
2.2.3 Protection Control
2.2.3.1 High Pressure Protection Control
System will enable high pressure protection control if the high pressure switch is detected open for
continuously a little time. Under high pressure protection, system will be shut down and display error code E1.
When high pressure protection occurs for the first time, system will restore operation if the high pressure
switch is detected to be reclosed for continuously a little time. When high pressure protection occurs for the
second time in a certain time period, system will not restore operation. You need to manually turn off the unit and
clear the error before restarting up the unit. (If high pressure protection occurs frequently, please send for
professional personnel to repair.)
2.2.3.2 Low Pressure Protection Control
System will enable low pressure protection control if the low pressure switch is detected open for
continuously a little time. Under low pressure protection, system will be shut down and display error code E3.
When low pressure protection occurs, system will restore operation if the low pressure switch is detected to be
reclosed within a few minutes after shutdown. If low pressure protection occurs for several times in a period of
time, system will not restore operation automatically. You need to manually turn off the unit before restarting up
the unit.
2.2.3.3 High Temperature Prevention Control
Under heating mode, system will enable high temperature prevention control if the temperature sensed by
indoor tube temperature sensor reaches a certain value. When high temperature prevention control is enabled,
outdoor fan will slow down.
2.2.3.4 Discharge High Temperature Protection Control
System will enable discharge temperature protection control if the discharge high temperature sensor is
SERVICE MANUAL
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