LG A2UW18GFAC Manual page 163

MULTI
4. Refrigerant Piping System
■ Piping System between outdoor unit / indoor unit
Outdoor Unit
L1
 Refrigerant additional charge calculation method
Additional charge (g) = [(L1 + L2 + L3 + L4) – (A x CF1)] x a – (CF2 x 150)
L1~L4 (m) : Installed Piping Length (Outdoor Unit ~ Indoor Unit)
A (m) : Charge-less piping length
a (g/m) : Additional charging volume for Main Pipe (Outdoor Unit ~ Indoor Unit)
CF1 : Total number of connected indoor unit ÷ Max. number of connectable indoor unit
CF2 : Max. number of connectable indoor unit – Total number of connected indoor unit
* Refer to the specifications for detail information of A, a.
* If total additional charge value after calculation comes out to be negative, then do not consider additional charge.
 Caution
• Please check the product type. Piping installation and refrigerant charge varies depending on the type of
product. For more information, please refer to the installation manual.
• Capacity is based on standard length and maximum allowance length is on the basis of reliability.
• Improper refrigerant charge may result in abnormal cycle.
Indoor Unit
Indoor Unit
L2
L3
Indoor Unit
L4
Indoor Unit
Installation of Outdoor Units
When the outdoor unit is installed in
a higher position than the indoor unit,
Oil trap is necessary.
Notes
L1 ~ L4 (m) : Piping Length
(Outdoor Unit ~ Indoor Unit)
H1 (m) : Height Difference
(Outdoor Unit ~ Indoor Unit)
H2 (m) : Height Difference
(Indoor Unit ~ Indoor Unit)
Refer to the specifications of Outdoor Unit for Maximum limit
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