LG LMCN185HV Installation Instructions - Page 44

Charging Charging I Each outdoor unit is factory charged (see rating plate) for the evaporator as well as a 7.5m(25ft) line set for each indoor line. Any time total line set is used either shorter or longer than the nominal 7.5*ID No. m(25*ID No. ft) line set length the refrigerant charge has to be adjusted. I Whether the line set is made shorter or longer you must adjust the charge based on how many ft of tubing are either added or removed based on 20g/m(0.22oz/ft) of R-410A per meter(foot). Unit:m(ft) Outdoor Unit Capacity (Btu/h class) Max total length of all pipes (A+B)/(A+B+C)/ (A+B+C+D) Max length of each pipe (A/B/C/D) Min length of each pipe (A/B/C/D) Max Elevation between each indoor unit and outdoor unit (h1) Max elevation between indoor units (h2) Additional Piping Refrigerant Length(no add'l Unit : g/m (oz/ft) refrigerant) 18k 50(164) 25(82) 3(10) 15(49) 7.5(25) 20(0.22) 22.5(74) 24k 75(246) 25(82) 3(10) 15(49) 7.5(25) 20(0.22) 37.5(128) 36k 75(246) 25(82) 3(10) 15(49) 7.5(25) 20(0.22) 37.5(128) Important: If you are ever uncertain of the unit charge, reclaim, evacuate and weigh in the correct charge using the charge amount specified on the unit's rating plate, adjusting for line sets longer or shorter than 7.5m(25ft) for each indoor unit. Additional charge(g) = [(A Room Installation Length - Standard Length ) x 0.22 oz/ft + (B Room Installation Length - Standard Length ) x 0.22 oz/ft +.. ] - CF(Correction Factor) x 1.61 oz ❈ CF = Max. number of connectable indoor unit - Total number of connected indoor unit a 9k b 9k Each branch pipe a=82ft b=16ft c=49ft Ex) A4UW363FA0 c 9k Additional Charge = (82-25) x 0.22 + (16-25) x 0.22 + (49-25) x 0.22 - (4-3) x 1.61 = 12.54 - 1.98 + 5.28 - 1.61 =14.23 oz ❈ If the total additional charge value after calculation comes out to be negative, then do not consider additional charge. 44 Multi Air Conditioner