Fn 9 Low Ambient Kit - LG MULTI V 5 Manual Book

4.9 Low Ambient Kit
It is a function to Informs the Multi V microprocessor controller the low ambient kit is installed.
■ Setting the function
Function
Low Ambient Kit
■ Option Selection
Setting
on Low ambient kit installation
oFF
■ Detailed information
• This function is used with heat pump and heat recovery.
(However, the kit does not extend the range of cooling below -15℃(5ºF) unless all indoor units are
operating in cooling when heat recovery is used)
• Low ambient cooling modes is a change in the setting impact.
• The operating symptoms that might be corrected using this function
This option assist the Multi V core logic maintain compressor suction pressure at low ambient tem-
peratures.
• In buildings where the zones served by the Multi V system will all need cooling when outdoor am-
bient temperatures fall below 5℉.
• Operation range after installation of low ambient kit
Before : -15~48℃ / After : -25~48℃ (detailed refer to the manual)
· Ask an authorized technician to setting a function.
· If do not use a function, set an off-mode.
· If low ambient kit is installed, this function must be enabled.
· Refer to the accessory manual or PDB for how to set up and use the guide.
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Option
Fn 9 on, oFF
Detail of function
Not setting (Default)
4.10 High Efficiency Mode
High efficiency mode refers to increasing the compressor capability to cool at high ambient temperatures.
This function automatically lowers the target low pressure as the outdoor ambient temperature rises while
the outdoor unit operates in cooling mode (i.e. reversing valve in cooling position).
■ Setting the function
Function
High Efficiency Mode
■ Option Selection
Setting
on
oFF
■ Detailed information
• This function is used with heat pump and heat recovery.
• Cooling and Dry modes is a change in the setting impact.
• The operating symptoms that might be corrected using this function
On extremely hot days when cooling demand is the highest, depending on the capacity of the out-
door unit relative to the actual load, if the VRF system is struggling to keep the space temperature,
invoking this option may be the solution to provide a little more capacity to meet the need.
• High efficiency mode can be used for all cooling dominant installations. Using this option will provide
additional cooling capacity, but will do so by increasing the amount of work (i.e. raises lift) the
compressor will perform. Net energy consumed may increase if this option is invoked.
· Ask an authorized technician to setting a function.
· If do not use a function, set an off-mode.
· Always verify the refrigerant charge is correct before using this function. If the refrigerant charge is
low, the use of this function will not provide any benefit.
Option
Fn 10 on, oFF
Detail of function
High efficiency mode
Default
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