Vapor density (ρ, lb/ft³) is the inverse of specific volume: ρ = 1 ÷ SV. It converts suction volumetric flow to mass flow rate: MFR ≈ ρ × V̇.
This tool estimates MFR as (tons × 12,000) ÷ Field NRE lb/min — pounds of refrigerant circulated per minute to deliver the rated cooling load.
Heat of Compression (HoC) is BTU per pound added during compression. Compressor heat load scales with MFR × HoC. Higher superheat lowers vapor density, so the compressor must move more volume for the same mass flow.
Isentropic = ideal compression with no heat loss or friction.
| Temperature (°F) | Liquid psig | Vapor psig |
|---|
Liquid (Bubble Point) & Vapor (Dew Point) • Mildly zeotropic blend — glide ~1.5°F
Use dew for superheat, bubble for subcooling.
Typical field gauges: suction ~100–140 psig, liquid ~380–465 psig