RefrigerantASHRAE R-1270

R1270 PT Chart

Updated October 12, 2026

R-1270

A3 Lower toxicity, higher flammabilityHydrocarbon

Illustration of a refrigerant cylinder painted light green gray (RAL 7044), the color AHRI Guideline N-2017 calls for on all new refrigerant containers from 2020^{[1], section 4.8}. Label: R-1270, safety class A3, GWP 1.8. Red band on the shoulder: AHRI Guideline N-2017 calls for one on containers of flammable refrigerants^{[1], section 4.7}.

C3H6

Hydrocarbon refrigerant — propylene (propene), C₃H₆. Higher capacity than R-290 propane, similar pressure profile. A3 highly flammable; GWP 2. Restricted to industrial refrigeration and specialty applications with HC-rated equipment.

R-1270 saturation pressure is 81.8 PSIG at 40°F, 137.1 PSIG at 70°F, and 212.6 PSIG at 100°F. These are the gauge readings on a static, fully-saturated system; a running system's high side sits well above them. The full table below runs from −40°F to 150°F in 1°F steps.

Not yet checked against an independent source.

Saturation @ 70°F

137.1 PSIG

GWP (100-yr)

1.8 US EPA value, 40 CFR 84.64(b)

Boiling point

−53.7°F

R-1270 PT calculator Superheat

R-1270 PT chart — printable saturation table

Looking for the R-1270 PT chart PDF for shop reference? The complete pressure-temperature saturation table is below: every 1° increment from −40°F to 150°F (or to the refrigerant's critical temperature). Use the Print / Save as PDF button in the table header to download a clean, table-only PDF (the rest of the page is hidden from the print output).

R-1270 PT Chart — Pressure-Temperature Saturation Table

Computed with CoolProp 7.2.0 in 1°F steps · hvacptcharts.com

R-1270 · 1° increments · °F / PSIG

Tinted rows: 32°F H₂O freeze

R-1270 pressure-temperature saturation table in Fahrenheit and PSIG
Temp (°F)	Pressure (PSIG)
−40°F	5.8
−39°F	6.3
−38°F	6.8
−37°F	7.3
−36°F	7.8
−35°F	8.3
−34°F	8.9
−33°F	9.4
−32°F	10.0
−31°F	10.5
−30°F	11.1
−29°F	11.7
−28°F	12.3
−27°F	12.9
−26°F	13.5
−25°F	14.1
−24°F	14.7
−23°F	15.3
−22°F	16.0
−21°F	16.7
−20°F	17.3
−19°F	18.0
−18°F	18.7
−17°F	19.4
−16°F	20.1
−15°F	20.9
−14°F	21.6
−13°F	22.3
−12°F	23.1
−11°F	23.9
−10°F	24.7
−9°F	25.5
−8°F	26.3
−7°F	27.1
−6°F	27.9
−5°F	28.8
−4°F	29.6
−3°F	30.5
−2°F	31.4
−1°F	32.3
0°F	33.2
1°F	34.1
2°F	35.1
3°F	36.0
4°F	37.0
5°F	38.0
6°F	38.9
7°F	40.0
8°F	41.0
9°F	42.0
10°F	43.1
11°F	44.1
12°F	45.2
13°F	46.3
14°F	47.4
15°F	48.5
16°F	49.7
17°F	50.8
18°F	52.0
19°F	53.2
20°F	54.4
21°F	55.6
22°F	56.8
23°F	58.1
24°F	59.3
25°F	60.6
26°F	61.9
27°F	63.2
28°F	64.5
29°F	65.9
30°F	67.2
31°F	68.6
32°F H₂O freeze	70.0
33°F	71.4
34°F	72.9
35°F	74.3
36°F	75.8
37°F	77.3
38°F	78.8
39°F	80.3
40°F	81.8
41°F	83.4
42°F	85.0
43°F	86.5
44°F	88.2
45°F	89.8
46°F	91.4
47°F	93.1
48°F	94.8
49°F	96.5
50°F	98.2
51°F	100.0
52°F	101.7
53°F	103.5
54°F	105.3
55°F	107.2
56°F	109.0
57°F	110.9
58°F	112.8
59°F	114.7
60°F	116.6
61°F	118.6
62°F	120.5
63°F	122.5
64°F	124.5
65°F	126.6
66°F	128.6
67°F	130.7
68°F	132.8
69°F	134.9
70°F	137.1
71°F	139.3
72°F	141.4
73°F	143.7
74°F	145.9
75°F	148.2
76°F	150.4
77°F	152.7
78°F	155.1
79°F	157.4
80°F	159.8
81°F	162.2
82°F	164.6
83°F	167.1
84°F	169.6
85°F	172.1
86°F	174.6
87°F	177.1
88°F	179.7
89°F	182.3
90°F	184.9
91°F	187.6
92°F	190.2
93°F	192.9
94°F	195.7
95°F	198.4
96°F	201.2
97°F	204.0
98°F	206.8
99°F	209.7
100°F	212.6
101°F	215.5
102°F	218.4
103°F	221.4
104°F	224.4
105°F	227.4
106°F	230.5
107°F	233.5
108°F	236.6
109°F	239.8
110°F	242.9
111°F	246.1
112°F	249.4
113°F	252.6
114°F	255.9
115°F	259.2
116°F	262.5
117°F	265.9
118°F	269.3
119°F	272.7
120°F	276.2
121°F	279.7
122°F	283.2
123°F	286.7
124°F	290.3
125°F	293.9
126°F	297.6
127°F	301.2
128°F	305.0
129°F	308.7
130°F	312.5
131°F	316.3
132°F	320.1
133°F	324.0
134°F	327.9
135°F	331.8
136°F	335.8
137°F	339.8
138°F	343.8
139°F	347.9
140°F	352.0
141°F	356.1
142°F	360.3
143°F	364.5
144°F	368.8
145°F	373.1
146°F	377.4
147°F	381.7
148°F	386.1
149°F	390.5
150°F	395.0

R-1270 pressure-temperature saturation table in Celsius and kPa
Temp (°C)	Pressure (kPa)
−40°C	40
−39°C	46
−38°C	52
−37°C	59
−36°C	66
−35°C	73
−34°C	80
−33°C	87
−32°C	95
−31°C	102
−30°C	110
−29°C	119
−28°C	127
−27°C	136
−26°C	145
−25°C	154
−24°C	164
−23°C	173
−22°C	183
−21°C	194
−20°C	204
−19°C	215
−18°C	226
−17°C	238
−16°C	250
−15°C	262
−14°C	274
−13°C	287
−12°C	300
−11°C	313
−10°C	327
−9°C	341
−8°C	355
−7°C	370
−6°C	385
−5°C	400
−4°C	416
−3°C	432
−2°C	449
−1°C	466
0°C H₂O freeze	483
1°C	500
2°C	518
3°C	537
4°C	556
5°C	575
6°C	595
7°C	615
8°C	635
9°C	656
10°C	677
11°C	699
12°C	721
13°C	744
14°C	767
15°C	791
16°C	815
17°C	839
18°C	864
19°C	890
20°C	916
21°C	942
22°C	969
23°C	997
24°C	1,025
25°C	1,053
26°C	1,082
27°C	1,112
28°C	1,142
29°C	1,172
30°C	1,204
31°C	1,235
32°C	1,268
33°C	1,301
34°C	1,334
35°C	1,368
36°C	1,403
37°C	1,438
38°C	1,474
39°C	1,510
40°C	1,547
41°C	1,585
42°C	1,623
43°C	1,662
44°C	1,701
45°C	1,742
46°C	1,782
47°C	1,824
48°C	1,866
49°C	1,909
50°C	1,952
51°C	1,997
52°C	2,042
53°C	2,087
54°C	2,134
55°C	2,181
56°C	2,228
57°C	2,277
58°C	2,326
59°C	2,376
60°C	2,427
61°C	2,479
62°C	2,531
63°C	2,584
64°C	2,638
65°C	2,693
66°C	2,748

CoolProp 7.2.0 · PSIG/kPa = gauge · PSIA = PSIG + 14.6959 · kPa(abs) = kPa(gauge) + 101.325

Full saturation values at 1° increments. Toggle between °F / PSIG and °C / kPa. Use Print / Save as PDF for laminated shop reference, or download the CSV / JSON below for use in other tools. R-1270 PT chart data: CoolProp 7.2.0 (published Helmholtz equations of state / mixture models — see the source citations above).

Lower toxicity, higher flammability

Lower toxicity, higher flammability. ASHRAE 34 class 3: lower flammability limit ≤ 0.10 kg/m³ or heat of combustion ≥ 19,000 kJ/kg. Includes hydrocarbons R-290 (propane), R-600a (isobutane), R-1150 (ethylene), R-1270 (propylene).

Flammability: Higher (LFL ≤ 0.10 kg/m³ or HoC ≥ 19,000 kJ/kg)
Toxicity: Lower

Classification per ANSI/ASHRAE Standard 34-2022. See full reference.

Saturation pressure-temperature curve

Pressure

Temperature

Highlight at°F

Quick lookup — R-1270

Temp:°F

137.1PSIG(945 kPa)

Range: −40 to 150°F Open full PT calculator →

Common service temperatures

32°F

70PSIG

Freezing

45°F

90PSIG

Heat-pump heat

70°F

137PSIG

Standard

75°F

148PSIG

Test ref

80°F

160PSIG

Warm

95°F

198PSIG

Summer peak

Saturation values from CoolProp 7.2.0^[2]. Operating pressure on a running system differs — see the operating-pressure references for in-use values.

At a glance

Chemistry

C3H6

Propylene

Lubricant compatibility

MOABPAOPOE

Highly flammable (A3). Used in industrial refrigeration where flammability can be managed. Mineral oil is standard; HC-rated equipment design is mandatory.

Common applications

Industrial refrigeration (specialty)
Ethylene production cascade systems
Some commercial refrigeration in regions with HC-rated equipment

Properties

Boiling point (1 atm)
−53.7°F (−47.6°C)
Critical point
195.9°F (91.1°C) at 646 PSIG
Molar mass
42.08 g/mol
ODP
0
GWP (100-yr)
1.8 US EPA value, 40 CFR 84.64(b) IPCC: AR4 not assessed · AR5 not assessed · AR6 not assessed 40 CFR 84.64(b) uses 1.8, the AR4 indirect GWP (Table 2.15).
Atmospheric lifetime
0.001 years
New-equipment status (US)
Not an AIM Act regulated substance; 40 CFR 84.54 GWP limits don't apply.

What is R-1270?

R-1270 is propylene (propene, CH₂=CHCH₃) — an unsaturated three-carbon hydrocarbon. Chemically distinct from propane (R-290, CH₃CH₂CH₃) by a single carbon-carbon double bond, but with very similar pressure-temperature behavior and slightly higher volumetric capacity. As a refrigerant, R-1270 sits in the hydrocarbon category alongside R-290 (propane), R-600a (isobutane), and R-1150 (ethylene).

Like all hydrocarbons used as refrigerants, R-1270 is A3 — highly flammable. The flammable charge limits under IEC 60335-2-89 (commercial refrigeration) and ASHRAE 15 / IEC 60335-2-40 (HVAC) cap practical applications: industrial refrigeration, ethylene production cascade systems, certain commercial refrigeration with sealed equipment design. Residential AC use is impractical because of charge restrictions and code limitations.

Where R-1270 is used

Industrial refrigeration (chemical plants, gas processing) where the chemistry of the plant already involves hydrocarbons
Ethylene production cascade systems (R-1270 condenses ethylene, R-1150)
Some commercial refrigeration in EU markets with HC-rated sealed equipment
Cryogenics adjacent applications

Regulatory & phase-down status

R-1270 is not on the AIM Act phase-down list — its GWP of 2 places it far below any phase-down threshold. The barrier to wider adoption is not regulatory but practical: A3 flammability, charge limits in residential and light commercial codes, and the need for spark-resistant equipment design.

Service notes

R-1270 service requires hydrocarbon-rated equipment training. Standard HVAC service practices need adaptation: brazing requires nitrogen purge to prevent oxidation AND to displace the flammable refrigerant; electrical components in the refrigerant space must be intrinsically safe or hermetically sealed; recovery cylinders must be rated for hydrocarbons.

Mineral oil (MO), alkylbenzene (AB), and PAO oils are compatible. POE oil is not used. EPA Section 608 covers refrigerant handling, but hydrocarbon-specific OSHA and NFPA requirements also apply to the installation and service environment.

Operating cycle

Phase-down timeline

R-1270 is not an AIM Act regulated substance (not one of the 18 HFCs in 42 U.S.C. 7675(c), and not a blend containing one). The 40 CFR 84.54 GWP limits don't apply.

Global warming potential, in context

Industrial refrigeration & cascade systems

Retrofit and replacement paths

Replacements for R-1270

R-1270 vs R-290, R-744: saturation pressure

Saturation pressure (PSIG, gauge) for R-1270 vs R-290, R-744. Each column shows the percent difference from R-1270. Source: CoolProp 7.2.0 dataset.
Temp	R-1270	R-290	R-744
0°F	33.2	23.7(−29%)	291.0(+777%)
40°F	81.8	63.9(−22%)	552.9(+576%)
70°F	137.1	110.2(−20%)	838.1(+511%)
100°F	212.6	173.9(−18%)	—

Frequently asked

›How does R-1270 compare to R-290 (propane)?

Very similar pressure profile and slightly higher volumetric capacity. R-1270's normal boiling point is −53.7°F vs R-290's −43.8°F — R-1270 has slightly higher vapor pressure at any given temperature, giving 5-10% more capacity per unit compressor displacement. Both are A3 (highly flammable), GWP 2-3.3, hydrocarbon. The practical choice between them often comes down to local availability and equipment OEM preference.

›Is R-1270 the same as propylene used in plastics manufacturing?

Chemical-grade or polymer-grade propylene can have moisture content and trace impurities that are fine for plastics manufacturing but unsuitable for refrigeration. Always use refrigerant-grade R-1270 with proper documentation.

›What kind of equipment uses R-1270?

Primarily large industrial refrigeration in process industries — chemical plants, refineries, natural gas processing — where the facility infrastructure is already designed for hydrocarbons. Ethylene production uses an R-1270/R-1150 cascade refrigeration system to liquefy ethylene at −150°F or below. Some commercial refrigeration in Europe uses R-1270 in sealed display cases with managed charge.

›Can I use R-1270 in a residential AC system?

Not practically. A3 refrigerant (R-1270, R-290, R-600a) requires specific equipment design (intrinsically safe controls, sealed compressor compartment, ventilation interlocks).

›What is the GWP of R-1270?

2. Essentially zero — hydrocarbon refrigerants have direct GWPs in the single digits because their atmospheric lifetimes are days to weeks (oxidized by OH radicals in the troposphere), unlike HFC/HFO refrigerants which persist for months to centuries. The low GWP is the main attraction of natural refrigerants.

Download this dataset

Full PT chart for R-1270 · CC BY 4.0 · attribute the source

CSV JSON

Sources & citations

[1]
2017 Guideline for Assignment of Refrigerant Container Colors (AHRI Guideline N-2017). AHRI. 2017. https://www.ahrinet.org/system/files/2023-06/AHRI_Guideline_N_2017.pdf (accessed October 2, 2026)
[2]
CoolProp 7.2.0. CoolProp (I. H. Bell, J. Wronski, S. Quoilin, V. Lemort). https://coolprop.org/ (accessed October 2, 2026). Bell, I. H.; Wronski, J.; Quoilin, S.; Lemort, V. Pure and Pseudo-pure Fluid Thermophysical Property Evaluation and the Open-Source Thermophysical Property Library CoolProp. Ind. Eng. Chem. Res. 53, 2498–2508 (2014). https://doi.org/10.1021/ie4033999