REFRIGERANT CHARGE
REFRIGERANT CHARGE
lbs = factory + (line_oz/ft × extra ft)
tons
ft
RESULT
—
FILL IN ABOVE
Estimate only. EPA Section 608 certification required to handle refrigerant. Final charge verified by subcooling/superheat, not weight. Verify with a licensed HVAC contractor before purchase or installation.
About this calculator
This refrigerant charge calculator estimates how many pounds of refrigerant a residential split-system AC or heat pump should carry. The factory pre-charge typically covers a 15-foot or 25-foot line set; anything beyond that adds refrigerant by weight per linear foot of liquid line, scaled to refrigerant type (R-410A, R-32, R-454B). Final charge is verified with subcooling (TXV / EEV systems) or superheat (fixed-orifice systems) — never just by weight alone. ESTIMATE ONLY: this is a planning figure for line-set ordering, not an install procedure. Adding or removing refrigerant must be done by an EPA Section 608-certified technician.
Common questions
How is final refrigerant charge actually verified?
Subcooling for TXV / EEV systems (most modern equipment): measure liquid line temp at the condenser, compare to saturation temp at liquid pressure, target the manufacturer's subcooling spec (typically 8-12°F). Superheat for fixed-orifice systems: measure suction line temp at the condenser, compare to saturation at suction pressure, target the chart on the equipment.
Do I need a Section 608 license to handle refrigerant?
Yes. EPA Section 608 of the Clean Air Act requires technician certification to purchase, recover, recycle, or charge refrigerant. Type II covers high-pressure (most residential), universal covers everything. Selling or charging refrigerant without certification is a federal violation with up to $44,539 per day per violation.
Why is R-410A being phased out?
GWP (global warming potential). R-410A has a GWP of 2,088. Under the AIM Act, US residential systems must use refrigerants with GWP under 700 starting January 1, 2025 — R-454B (GWP 466) and R-32 (GWP 675) are the two main replacements. Existing R-410A systems can keep running, but new manufacture is being phased out.