HVAC Toolkit

Pressure-Temperature Charts

Saturation P-T data for common refrigerants

Select Refrigerant

HFC / HCFC

R-22 R-32 R-125 R-134a R-143a R-404A Z R-407C Z R-410A R-507A

Low GWP (HFO)

R-449A Z R-454B Z Low GWP R-513A R-1234yf Low GWP R-1234ze(E) Low GWP

Natural

R-290 (Propane) Low GWP R-600a (Isobutane) Low GWP R-744 (CO2) Low GWP R-717 (NH3) Low GWP

Pressure Unit

psig kPa bar kgf/cm²

R-407C

Zeotropic
GWP: 1,774
ODP: 0
Temperature Glide: 7°C

Quick P-T Lookup

kPa

* Results are interpolated from the P-T table data

Z

Zeotropic Blend

This refrigerant has a temperature glide of 7°C - use the correct saturation point!

Temperature Glide Visualization

Dew Point
100% Vapor
For Superheat
7°C Glide
Higher Temp Lower Temp
Bubble Point
100% Liquid
For Subcooling

DEW Suction Side / Superheat

  • • Superheat = Suction Temp - Dew Point Temp
  • • Use at evaporator outlet
  • • Low pressure gauge reading
  • • Temperature where last liquid evaporates

BUBBLE Liquid Side / Subcooling

  • • Subcooling = Bubble Point Temp - Liquid Temp
  • • Use at condenser outlet
  • • High pressure gauge reading
  • • Temperature where first bubble forms

Important: Using the wrong saturation point will give incorrect superheat/subcooling readings. For R-407C with 7°C glide, this error can significantly affect diagnosis and charging.

Dew Point (Vapor)

Used for suction line / evaporator

°C °F kPa
-40 -40 129.0
-35 -31 171.0
-30 -22 221.0
-25 -13 278.0
-20 -4 344.0
-15 5 418.0
-10 14 503.0
-5 23 598.0
0 32 704.0
5 41 822.0
10 50 953.0
15 59 1,098.0
20 68 1,256.0
25 77 1,429.0
30 86 1,618.0
35 95 1,824.0
40 104 2,048.0
45 113 2,290.0
50 122 2,552.0
55 131 2,833.0
60 140 3,134.0

Bubble Point (Liquid)

Used for liquid line / condenser

°C °F kPa
-40 -40 82.0
-35 -31 118.0
-30 -22 160.0
-25 -13 209.0
-20 -4 266.0
-15 5 331.0
-10 14 405.0
-5 23 487.0
0 32 580.0
5 41 684.0
10 50 798.0
15 59 925.0
20 68 1,065.0
25 77 1,218.0
30 86 1,385.0
35 95 1,567.0
40 104 1,766.0
45 113 1,982.0
50 122 2,215.0
55 131 2,467.0
60 140 2,738.0

Pressure Units: psig = Gauge pressure (relative to atmosphere) kPa / bar / kgf/cm² = Absolute pressure