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-449A

Zeotropic
GWP: 1,397
ODP: 0
Safety Class: A1
Temperature Glide: 6°C

Retrofit replacement for R-404A/R-507A. Lower discharge temp than R-404A. Requires POE oil. Use dew point for superheat, bubble point for subcooling.

Quick P-T Lookup

psig

* Results are interpolated from the P-T table data

Z

Zeotropic Blend

This refrigerant has a temperature glide of 6°C - use the correct saturation point!

Temperature Glide Visualization

Dew Point
100% Vapor
For Superheat
6°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-449A with 6°C glide, this error can significantly affect diagnosis and charging.

Dew Point (Vapor)

Used for suction line / evaporator

°C °F psig
-50 -58 -2.1
-45 -49 3.7
-40 -40 10.3
-35 -31 17.9
-30 -22 26.6
-25 -13 36.5
-20 -4 47.7
-17.8 0 54.0
-15 5 60.4
-10 14 74.6
-5 23 90.4
0 32 108.0
5 41 127.5
10 50 148.9
15 59 172.5
20 68 198.2
25 77 226.4
30 86 257.0
35 95 290.2
40 104 326.2
45 113 365.0
50 122 406.8
55 131 451.8
60 140 500.2

Bubble Point (Liquid)

Used for liquid line / condenser

°C °F psig
-50 -58 4.2
-45 -49 10.8
-40 -40 18.4
-35 -31 27.1
-30 -22 37.0
-25 -13 48.2
-20 -4 60.8
-17.8 0 68.3
-15 5 75.0
-10 14 90.8
-5 23 108.5
0 32 128.0
5 41 149.5
10 50 173.1
15 59 199.0
20 68 227.2
25 77 258.0
30 86 291.4
35 95 327.6
40 104 366.8
45 113 409.0
50 122 454.6
55 131 503.8
60 140 556.8

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