Suction Line Size Calculator
Suction line sizing balances oil-return velocity against pressure drop. The working calculator checks the selected vapor line ID, equivalent length and entered refrigerant properties.
suction line size calculator suction line size calculator by capacity and length refrigerant velocity for oil return calculator
Suction velocity
v_suction = m_dot / (rho_vapor * A_suction)
Pressure drop
dp = f * (L / D) * rho * v^2 / 2
Oil-return caution
Oil return depends on compressor, refrigerant, load condition, risers, traps and manufacturer long-line rules. Treat velocity as a screen, not an approval.
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