Refrigerant Line Set Additional Charge Calculator
Calculate exact additional refrigerant trim charge (ounces and grams) for split AC and heat pump line sets exceeding factory precharge length across R-410A, R-32, and R-454B systems by liquid line diameter.
System & Line Set Parameters
ft
ft
Found on outdoor unit rating plate (usually 15ft or 25ft).
Additional Refrigerant Charge
35 FT EXCESS LENGTH
21.0 oz
1 lb 5.0 oz (595 Grams) required trim charge
Multiplier per Foot
0.60 oz / ft
55.8 g / meter
Total Grams
595 g
Digital charging scale target
Weigh-in Procedure Guidelines
Always weigh in trim charge as pure liquid into the liquid service port with system evacuated to ≤ 500 microns prior to opening outdoor service valves.