BackReadings in — the chart draws itself
Enthalpy chart
Pressure–enthalpy · live physics
Healthy cycle
6.0 K superheat · 4.0 K subcool
Refrigerant
GWP 675A2L
The cycle
Type what the gauges say — the chart draws itself.
Both pressures set the cycle — superheat and subcool need the line temps too.
What the chart is saying
6.0 K superheat — the coil boils everything off with room to spare, so only dry gas reaches the compressor.
4.0 K subcooling — solid liquid at the expansion device, and every extra kelvin here is capacity for free.
27% flashes to gas across the expansion device just to cool the rest of the liquid down — that gas does no cooling in the coil. More subcooling, less flash.
Compression ratio 4.0:1 — comfortable for a single-stage compressor.
Layers
Where the readings come from
Numbers match the chart. Red hot to blue cold — the dot you clamp is the point it fixes.
State at each stage
1Compressor suctionSuperheated vapour — all gas, 6.0 K above dew521 kJ/kg · 5.9 barg · 1.0°C
2Compressor dischargeSuperheated vapour — hot, high pressure560 kJ/kg · 26.9 barg · 75°C
3Liquid lineSubcooled liquid — 4.0 K below bubble278 kJ/kg · 26.9 barg · 41.0°C
4After expansionTwo-phase — 27% flash gas, 73% liquid278 kJ/kg · 5.9 barg · -5.0°C
What the cycle moves
243 kJ/kg
Refrigeration effect
39 kJ/kg
Compression work
282 kJ/kg
Heat rejected
6.29
COP (ideal, cooling)
Saturation and superheat tables are the app’s published refrigerant data — the same numbers the diagnostic chart runs on. The axis shows absolute pressure (log scale); readouts show gauge alongside.