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-454B

Zeotropic
GWP: 466
ODP: 0
Safety Class: A2L
Temperature Glide: 1.3°C

Low GWP alternative to R-410A. Also known as Opteon XL41. Mildly flammable (A2L), requires proper handling and equipment rated for A2L refrigerants.

A2L Mildly Flammable - Use equipment rated for A2L refrigerants. Follow local safety codes.

Quick P-T Lookup

psig

* Results are interpolated from the P-T table data

Z

Zeotropic Blend

This refrigerant has a temperature glide of 1.3°C - use the correct saturation point!

Temperature Glide Visualization

Dew Point
100% Vapor
For Superheat
1.3°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-454B with 1.3°C glide, this error can significantly affect diagnosis and charging.

Dew Point (Vapor)

Used for suction line / evaporator

°C °F psig
-50 -58 -5.2
-45 -49 -0.6
-40 -40 4.8
-35 -31 11.0
-30 -22 18.2
-25 -13 26.5
-20 -4 35.9
-15 5 46.6
-10 14 58.7
-5 23 72.2
0 32 87.3
5 41 104.1
10 50 122.6
15 59 143.1
20 68 165.5
25 77 190.1
30 86 217.0
35 95 246.2
40 104 278.0
45 113 312.4
50 122 349.6
55 131 389.6
60 140 432.7
65 149 479.0
70 158 528.6

Bubble Point (Liquid)

Used for liquid line / condenser

°C °F psig
-50 -58 -6.0
-45 -49 -1.6
-40 -40 3.6
-35 -31 9.6
-30 -22 16.6
-25 -13 24.6
-20 -4 33.7
-15 5 44.1
-10 14 55.8
-5 23 69.0
0 32 83.7
5 41 100.0
10 50 118.0
15 59 138.0
20 68 159.8
25 77 183.7
30 86 209.8
35 95 238.2
40 104 269.0
45 113 302.4
50 122 338.5
55 131 377.3
60 140 419.1
65 149 463.8
70 158 511.7

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