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

kPa

* 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 kPa
-50 -58 65.0
-45 -49 95.0
-40 -40 132.0
-35 -31 175.0
-30 -22 225.0
-25 -13 282.0
-20 -4 348.0
-15 5 422.0
-10 14 505.0
-5 23 599.0
0 32 703.0
5 41 819.0
10 50 947.0
15 59 1,088.0
20 68 1,242.0
25 77 1,412.0
30 86 1,597.0
35 95 1,799.0
40 104 2,018.0
45 113 2,255.0
50 122 2,512.0
55 131 2,788.0
60 140 3,085.0
65 149 3,404.0
70 158 3,746.0

Bubble Point (Liquid)

Used for liquid line / condenser

°C °F kPa
-50 -58 59.0
-45 -49 88.0
-40 -40 124.0
-35 -31 165.0
-30 -22 214.0
-25 -13 269.0
-20 -4 333.0
-15 5 405.0
-10 14 486.0
-5 23 577.0
0 32 678.0
5 41 791.0
10 50 915.0
15 59 1,052.0
20 68 1,202.0
25 77 1,367.0
30 86 1,547.0
35 95 1,743.0
40 104 1,956.0
45 113 2,186.0
50 122 2,435.0
55 131 2,703.0
60 140 2,991.0
65 149 3,300.0
70 158 3,630.0

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