Refrigerant Line Charge Calculator

Inputs

Charge method

Use the equipment manual rate when available. Volume-density is a fallback screen when you know line ID and liquid density.

Installed line-set length (L)

Actual measured one-way refrigerant line-set length used by the equipment manual.

Factory-included length (L0)

Line length already covered by the factory charge or chargeless length.

Added charge rate (r)

Use the rate from the equipment manual, commonly listed in oz/ft or g/m.

g/m

Nameplate/factory charge (B)

Optional existing charge from the nameplate or manual. Leave zero to calculate added charge only.

Other manual adjustment (A)

Optional manual adjustment such as a branch-kit, coil, suction-line or model correction. Negative values are allowed when the manual subtracts an adjustment.

Results

Default result

Edit inputs

Net additional charge(C_net)

340.2g

Pass

Installed length exceeds the factory-included length; added charge is based on the entered rate.

Line-set charge plus any manual adjustment.

Also computed

Total charge with base(B + C_net)340.2g

Base charge plus net additional line-set charge.

Only meaningful when the nameplate/factory charge input is filled in.

Length beyond factory charge(L - L0)6.096m

Charge rate used(r)55.81g/m

Rate source: manufacturer rate.

Line-set charge before adjustment(C_line)340.2g

Manual adjustment used(A)0g

Added liquid-line volume(V_added)—cm³

Added charge stays flat through the included factory-charge length, then increases with line length and the entered charge rate.

Method notes 3 notes

Formula: net added charge = max(installed length - factory-included length, 0) * charge rate + manual adjustment.
Manufacturer manuals may use model-specific charge rates, line-size tables, branch-kit adders, suction-line adjustments, maximum total charge limits and rounding rules.
This calculator estimates charge only. It does not select suction/liquid line size, verify oil return, long-line accessories, evacuation, leak testing, subcooling/superheat or A2L safety requirements.