Wiki
Short, practical notes to help you interpret results from FluidTool. These pages are educational and do not replace codes, standards, manufacturer guidance, or local regulations.
GWP & ODP
What these environmental metrics mean, and how to interpret them responsibly.
Critical point
Critical temperature/pressure and what changes near the critical region.
Two-phase quality (Q)
How vapor quality works on the saturation line and why PT can be ambiguous there.
Saturation pressure vs temperature
Psat(T) and Tsat(P), superheat/subcooling intuition, and common pitfalls.
P-h Diagram
How to read a pressure-enthalpy chart: dome, quality, isolines, and cycle intuition.
Refrigerant PT Chart
How to interpret Tsat(P)/Psat(T), plus common pitfalls (gauge vs absolute, blends, glide).
Gauge vs Absolute Pressure (psig vs psia)
psig vs psia, bar(a) vs bar(g), and how to convert with local Patm (altitude matters).
Car A/C Pressure Chart
Static vs running pressures, why pressures vary, and how to use PT data safely (no “targets”).
R1234yf PT Chart
Saturation pressure vs temperature reference table for R1234yf (absolute units; not diagnostics).
R134a PT Chart
Saturation pressure vs temperature reference table for R134a (absolute units; not diagnostics).
R1234yf vs R134a PT
Compare saturation pressure vs temperature for R1234yf and R134a (automotive context; absolute units).
CO2 (R744) PT Chart
Saturation pressure vs temperature for CO2 (below critical point; absolute units).
Transcritical CO2 (R744) cycle
What transcritical CO2 means and why PT charts do not apply on the high side above the critical point.
R22 PT Chart
Saturation pressure vs temperature reference table for R22 (absolute units; not diagnostics).
R32 PT Chart
Saturation pressure vs temperature reference table for R32 (absolute units; not diagnostics).
R290 PT Chart
Saturation pressure vs temperature reference table for R290 (propane; absolute units; not diagnostics).
R404A PT Chart
Bubble and dew saturation pressure vs temperature for R404A (blend; absolute units).
R410A PT Chart
Bubble and dew saturation pressure vs temperature for R410A (blend; absolute units).
R407C PT Chart
Bubble and dew saturation pressure vs temperature for R407C (blend with glide; absolute units).
R507A PT Chart
Bubble and dew saturation pressure vs temperature for R507A (near-azeotropic blend; absolute units).
R600a PT Chart
Saturation pressure vs temperature reference table for R600a (isobutane; absolute units; not diagnostics).
R717 PT Chart
Saturation pressure vs temperature reference table for R717 (ammonia; absolute units; not diagnostics).
R718 PT Chart
Saturation pressure vs temperature reference table for R718 (water/steam; absolute units; not diagnostics).
R152A PT Chart
Saturation pressure vs temperature reference table for R152A (absolute units; not diagnostics).
R1233zd(E) PT Chart
Saturation pressure vs temperature reference table for R1233zd(E) (absolute units; not diagnostics).
R1234ze(E) PT Chart
Saturation pressure vs temperature reference table for R1234ze(E) (absolute units; not diagnostics).
R1234ze(Z) PT Chart
Saturation pressure vs temperature reference table for R1234ze(Z) (absolute units; not diagnostics).
R1336mzz(E) PT Chart
Saturation pressure vs temperature reference table for R1336mzz(E) (absolute units; not diagnostics).
R236FA PT Chart
Saturation pressure vs temperature reference table for R236FA (absolute units; not diagnostics).
R245fa PT Chart
Saturation pressure vs temperature reference table for R245fa (absolute units; not diagnostics).
Subcooling (ΔTsc)
What subcooling means, how to calculate it, and measurement pitfalls (pressure basis, blends).
Psychrometric Chart
How to read a moist air chart: Tdb, W, RH, dew point, and HVAC processes.
Dew Point
What dew point means, why it predicts condensation, and how it differs from RH.
Wet-bulb temperature (Twb)
What Twb means, why it matters for evaporative cooling, and how it differs from dew point.
RH vs Humidity Ratio (W)
Why RH changes with temperature while W tracks absolute moisture content.
Specific Humidity vs Humidity Ratio
q vs W (mixing ratio): definitions, conversions, and common terminology pitfalls.
Mixing Outdoor Air & Return Air
How to compute mixed air properties by mixing W and h (not RH).
Bubble vs Dew (Temperature Glide)
Bubble point, dew point, temperature glide, and how to interpret saturation for refrigerant blends.
Zeotropic vs Azeotropic
How refrigerant blends differ, why glide happens, and what it means for saturation interpretation.
Superheat & Subcooling
ΔTsh and ΔTsc definitions, how they relate to saturation, and measurement pitfalls.