Refrigerant PT Chart

Saturation pressures for every refrigerant here, side by side. Tap one for its full chart, every degree from -40 to 150°F, with a lookup.

Pressures side by side

Gauge pressure at sea level. Liquid (bubble) is the one to use for subcooling and vapor (dew) for superheat; a single number means liquid and vapor saturate at the same pressure. Glide is at a 40°F (4.4°C) dew point.

RefrigerantAt 40°FpsigAt 100°Fpsig
R-410AResidential ACGlide 0.2°FA1118.8 liquid118.4 vapor318.5 liquid317.6 vapor
R-454BNew AC systemsGlide 2.7°FA2L113.2 liquid107.5 vapor303.3 liquid291.9 vapor
R-32New AC systemsA2L121.0325.7
R-22Older systemsA168.6195.9
R-134aChillers, auto ACA135.0124.2
R-404ARefrigerationGlide 0.9°FA186.9 liquid85.4 vapor236.8 liquid234.7 vapor
R-407CR-22 replacementGlide 11.1°FA180.2 liquid63.2 vapor225.5 liquid196.1 vapor
R-507ARefrigerationGlide under 0.1°FA189.3 liquid89.2 vapor242.3 liquid242.1 vapor
R-448AR-404A replacementGlide 10.1°FA189.0 liquid72.1 vapor243.7 liquid214.3 vapor
R-449AR-404A replacementGlide 9.4°FA187.4 liquid71.8 vapor240.1 liquid213.1 vapor
RefrigerantAt 5°CkPaAt 40°CkPa
R-410AResidential ACGlide 0.1°CA1835 liquid832 vapor2,324 liquid2,317 vapor
R-454BNew AC systemsGlide 1.5°CA2L796 liquid756 vapor2,212 liquid2,131 vapor
R-32New AC systemsA2L8502,377
R-22Older systemsA14831,432
R-134aChillers, auto ACA1248915
R-404ARefrigerationGlide 0.5°CA1611 liquid600 vapor1,728 liquid1,714 vapor
R-407CR-22 replacementGlide 6.2°CA1565 liquid446 vapor1,648 liquid1,440 vapor
R-507ARefrigerationGlide under 0.1°CA1628 liquid627 vapor1,768 liquid1,767 vapor
R-448AR-404A replacementGlide 5.6°CA1626 liquid508 vapor1,779 liquid1,571 vapor
R-449AR-404A replacementGlide 5.2°CA1615 liquid506 vapor1,752 liquid1,561 vapor

A1 is nonflammable and A2L is mildly flammable.

How to read a PT chart

A PT chart gives the pressure a refrigerant boils and condenses at for each temperature. Where liquid and vapor are both present, in the evaporator and condenser coils, the gauge pressure and the refrigerant's temperature go together, so the chart turns one into the other.

A blend with glide boils across a range of temperatures, so its chart has two columns: liquid (bubble) for subcooling and vapor (dew) for superheat. The glide is how far apart they are at the same pressure. On R-407C, R-448A and R-449A it's 9 to 11°F (5 to 6°C), so reading the wrong column throws superheat or subcooling off by about that much.

The pressures are gauge readings at sea level. Below atmospheric pressure the full charts switch to inches of mercury vacuum, the way a compound gauge reads. Use the chart for the refrigerant on the unit's nameplate, and let the superheat and subcooling calculators do the lookup when you're charging.

Where the numbers come from

Every number here is a row from that refrigerant's own chart. R-410A, R-454B, R-32, R-22, R-134a, R-404A, R-407C and R-507A come from CoolProp 8.0.0, an open-source property library, solved at each exact temperature. The others come from the makers' published tables: R-448A from Arkema's Forane PT chart and R-449A from Chemours' Opteon XP40 tables. Each chart page lists its formula and the published tables it's checked against.

Sources

Updated