Refrigeration Pipe Sizing Calculator
Undersized suction lines starve the evaporator; oversized lines strand oil in the compressor. Correct sizing balances pressure drop (typically 0.5–1°C equivalent) against refrigerant velocity (oil return needs ~4–6 m/s in risers).
The full pipe-sizing tool covers suction, discharge and liquid lines with ΔP and oil-return checks for any of the supported refrigerants.
Undersized suction lines starve the evaporator; oversized lines strand oil in the compressor. Correct sizing balances pressure drop (typically 0.5–1°C equivalent) against refrigerant velocity (oil return needs ~4–6 m/s in risers).
Unlock the pipe sizing tool — free account →Frequently asked questions
What pressure drop should I design for in suction lines?
Industry practice: 0.5–1°C (1–2°F) equivalent temperature drop for suction lines, up to 0.5°C for discharge, and 0.5°C for liquid lines after the subcooling margin.
How fast does refrigerant need to travel for oil return?
In vertical risers, suction gas should exceed roughly 4–6 m/s for oil to carry. Below that, oil traps form — the tool flags this case explicitly.
Does line size affect system COP?
Yes. Suction-line pressure drop directly reduces the effective evaporating pressure at the compressor, cutting capacity and efficiency. The tool reports the equivalent temperature penalty so you can trade pipe cost against efficiency.
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