R-11
Pure CFC, trichlorofluoromethane (CCl₃F). ASHRAE A1. GWP 4750. ODP = 1.0 — R-11 is the REFERENCE refrigerant for ozone-depletion potential (all ODP values are normalized to R-11 = 1.0). US production banned January 1, 1996. Historical low-pressure centrifugal chiller refrigerant.
Lower toxicity (Occupational Exposure Limit ≥ 400 ppm). No flame propagation in air at standard atmospheric pressure and 60°C. R-134a, R-22, R-410A, R-404A, R-744 (CO2) are A1.
- Flammability
- None (no flame propagation)
- Toxicity
- Lower (OEL ≥ 400 ppm)
Classification per ANSI/ASHRAE Standard 34-2022. See full reference.
Saturation pressure-temperature curve
Saturation values from CoolProp 7.2.0 R11. Operating pressure on a running system differs — see the operating-pressure references for in-use values.
R-11 PT chart PDF — printable saturation table
Looking for the R-11 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). Important service temperatures (normal boiling point, freezing point of water, residential AC evap and condenser targets) are tinted and tagged in the table for at-a-glance shop reference.
R-11 PT Chart — Pressure-Temperature Saturation Table
1° increments · Source: CoolProp 7.2.0 / manufacturer datasheet · hvacptcharts.com
| Temp (°F) | Pressure (PSIG) |
|---|---|
| -40°F | -14.0 |
| -39°F | -13.9 |
| -38°F | -13.9 |
| -37°F | -13.9 |
| -36°F | -13.8 |
| -35°F | -13.8 |
| -34°F | -13.8 |
| -33°F | -13.8 |
| -32°F | -13.7 |
| -31°F | -13.7 |
| -30°F | -13.7 |
| -29°F | -13.6 |
| -28°F | -13.6 |
| -27°F | -13.6 |
| -26°F | -13.5 |
| -25°F | -13.5 |
| -24°F | -13.4 |
| -23°F | -13.4 |
| -22°F | -13.4 |
| -21°F | -13.3 |
| -20°F | -13.3 |
| -19°F | -13.2 |
| -18°F | -13.2 |
| -17°F | -13.1 |
| -16°F | -13.1 |
| -15°F | -13.0 |
| -14°F | -13.0 |
| -13°F | -12.9 |
| -12°F | -12.9 |
| -11°F | -12.8 |
| -10°F | -12.8 |
| -9°F | -12.7 |
| -8°F | -12.7 |
| -7°F | -12.6 |
| -6°F | -12.5 |
| -5°F | -12.5 |
| -4°F | -12.4 |
| -3°F | -12.3 |
| -2°F | -12.3 |
| -1°F | -12.2 |
| 0°F | -12.1 |
| 1°F | -12.1 |
| 2°F | -12.0 |
| 3°F | -11.9 |
| 4°F | -11.8 |
| 5°F | -11.8 |
| 6°F | -11.7 |
| 7°F | -11.6 |
| 8°F | -11.5 |
| 9°F | -11.4 |
| 10°F | -11.3 |
| 11°F | -11.3 |
| 12°F | -11.2 |
| 13°F | -11.1 |
| 14°F | -11.0 |
| 15°F | -10.9 |
| 16°F | -10.8 |
| 17°F | -10.7 |
| 18°F | -10.6 |
| 19°F | -10.5 |
| 20°F | -10.3 |
| 21°F | -10.2 |
| 22°F | -10.1 |
| 23°F | -10.0 |
| 24°F | -9.9 |
| 25°F | -9.8 |
| 26°F | -9.7 |
| 27°F | -9.5 |
| 28°F | -9.4 |
| 29°F | -9.3 |
| 30°F | -9.1 |
| 31°F | -9.0 |
| 32°FH₂O freeze | -8.9 |
| 33°F | -8.7 |
| 34°F | -8.6 |
| 35°F | -8.4 |
| 36°F | -8.3 |
| 37°F | -8.1 |
| 38°F | -8.0 |
| 39°F | -7.8 |
| 40°FChiller evap LCHW | -7.7 |
| 41°F | -7.5 |
| 42°F | -7.3 |
| 43°F | -7.2 |
| 44°F | -7.0 |
| 45°F | -6.8 |
| 46°F | -6.6 |
| 47°F | -6.5 |
| 48°F | -6.3 |
| 49°F | -6.1 |
| 50°F | -5.9 |
| 51°F | -5.7 |
| 52°F | -5.5 |
| 53°F | -5.3 |
| 54°F | -5.1 |
| 55°F | -4.9 |
| 56°F | -4.7 |
| 57°F | -4.5 |
| 58°F | -4.2 |
| 59°F | -4.0 |
| 60°F | -3.8 |
| 61°F | -3.6 |
| 62°F | -3.3 |
| 63°F | -3.1 |
| 64°F | -2.8 |
| 65°F | -2.6 |
| 66°F | -2.4 |
| 67°F | -2.1 |
| 68°F | -1.8 |
| 69°F | -1.6 |
| 70°F | -1.3 |
| 71°F | -1.0 |
| 72°F | -0.8 |
| 73°F | -0.5 |
| 74°F | -0.2 |
| 75°FNBP (atmospheric) | 0.1 |
| 76°F | 0.4 |
| 77°F | 0.7 |
| 78°F | 1.0 |
| 79°F | 1.3 |
| 80°F | 1.6 |
| 81°F | 1.9 |
| 82°F | 2.2 |
| 83°F | 2.6 |
| 84°F | 2.9 |
| 85°F | 3.2 |
| 86°F | 3.6 |
| 87°F | 3.9 |
| 88°F | 4.3 |
| 89°F | 4.6 |
| 90°F | 5.0 |
| 91°F | 5.3 |
| 92°F | 5.7 |
| 93°F | 6.1 |
| 94°F | 6.5 |
| 95°F | 6.9 |
| 96°F | 7.3 |
| 97°F | 7.7 |
| 98°F | 8.1 |
| 99°F | 8.5 |
| 100°FCond saturation | 8.9 |
| 101°F | 9.3 |
| 102°F | 9.7 |
| 103°F | 10.2 |
| 104°F | 10.6 |
| 105°F | 11.1 |
| 106°F | 11.5 |
| 107°F | 11.9 |
| 108°F | 12.4 |
| 109°F | 12.9 |
| 110°F | 13.4 |
| 111°F | 13.8 |
| 112°F | 14.3 |
| 113°F | 14.8 |
| 114°F | 15.3 |
| 115°F | 15.8 |
| 116°F | 16.3 |
| 117°F | 16.9 |
| 118°F | 17.4 |
| 119°F | 17.9 |
| 120°F | 18.4 |
| 121°F | 19.0 |
| 122°F | 19.6 |
| 123°F | 20.1 |
| 124°F | 20.7 |
| 125°F | 21.3 |
| 126°F | 21.8 |
| 127°F | 22.4 |
| 128°F | 23.0 |
| 129°F | 23.6 |
| 130°FHigh-side limit | 24.2 |
| 131°F | 24.9 |
| 132°F | 25.5 |
| 133°F | 26.1 |
| 134°F | 26.7 |
| 135°F | 27.4 |
| 136°F | 28.1 |
| 137°F | 28.7 |
| 138°F | 29.4 |
| 139°F | 30.1 |
| 140°F | 30.7 |
| 141°F | 31.4 |
| 142°F | 32.1 |
| 143°F | 32.9 |
| 144°F | 33.6 |
| 145°F | 34.3 |
| 146°F | 35.0 |
| 147°F | 35.8 |
| 148°F | 36.5 |
| 149°F | 37.3 |
| 150°F | 38.0 |
| Temp (°C) | Pressure (kPa) |
|---|---|
| -40°C | -96 |
| -39°C | -96 |
| -38°C | -96 |
| -37°C | -95 |
| -36°C | -95 |
| -35°C | -94 |
| -34°C | -94 |
| -33°C | -94 |
| -32°C | -93 |
| -31°C | -93 |
| -30°C | -92 |
| -29°C | -92 |
| -28°C | -91 |
| -27°C | -90 |
| -26°C | -90 |
| -25°C | -89 |
| -24°C | -89 |
| -23°C | -88 |
| -22°C | -87 |
| -21°C | -86 |
| -20°C | -86 |
| -19°C | -85 |
| -18°C | -84 |
| -17°C | -83 |
| -16°C | -82 |
| -15°C | -81 |
| -14°C | -80 |
| -13°C | -79 |
| -12°C | -78 |
| -11°C | -77 |
| -10°C | -76 |
| -9°C | -74 |
| -8°C | -73 |
| -7°C | -72 |
| -6°C | -70 |
| -5°C | -69 |
| -4°C | -68 |
| -3°C | -66 |
| -2°C | -64 |
| -1°C | -63 |
| 0°CH₂O freeze | -61 |
| 1°C | -59 |
| 2°C | -58 |
| 3°C | -56 |
| 4°CChiller evap LCHW | -54 |
| 5°C | -52 |
| 6°C | -50 |
| 7°C | -47 |
| 8°C | -45 |
| 9°C | -43 |
| 10°C | -41 |
| 11°C | -38 |
| 12°C | -36 |
| 13°C | -33 |
| 14°C | -30 |
| 15°C | -28 |
| 16°C | -25 |
| 17°C | -22 |
| 18°C | -19 |
| 19°C | -16 |
| 20°C | -13 |
| 21°C | -9 |
| 22°C | -6 |
| 23°C | -2 |
| 24°CNBP (atmospheric) | 1 |
| 25°C | 5 |
| 26°C | 8 |
| 27°C | 12 |
| 28°C | 16 |
| 29°C | 20 |
| 30°C | 25 |
| 31°C | 29 |
| 32°C | 33 |
| 33°C | 38 |
| 34°C | 43 |
| 35°C | 47 |
| 36°C | 52 |
| 37°C | 57 |
| 38°CCond saturation | 62 |
| 39°C | 68 |
| 40°C | 73 |
| 41°C | 79 |
| 42°C | 84 |
| 43°C | 90 |
| 44°C | 96 |
| 45°C | 102 |
| 46°C | 108 |
| 47°C | 115 |
| 48°C | 121 |
| 49°C | 128 |
| 50°C | 135 |
| 51°C | 142 |
| 52°C | 149 |
| 53°C | 156 |
| 54°CHigh-side limit | 164 |
| 55°C | 171 |
| 56°C | 179 |
| 57°C | 187 |
| 58°C | 195 |
| 59°C | 204 |
| 60°C | 212 |
| 61°C | 221 |
| 62°C | 229 |
| 63°C | 238 |
| 64°C | 248 |
| 65°C | 257 |
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-11 PT chart data: CoolProp 7.2.0 (REFPROP-compatible Helmholtz EOS) or manufacturer datasheet, validated against AHRI Standard 700-2019.
At a glance
Chemistry
Lubricant compatibility
Mineral oil is the historical standard. R-11 is a low-pressure refrigerant historically used in centrifugal chillers.
Trade names
- Freon 11Chemours (historical: DuPont)
- Genetron 11Honeywell
Common applications
- Centrifugal chillers (historical, large-tonnage)
- Low-pressure refrigeration systems (legacy)
- Reference fluid for ODP definition (R-11 = 1.0)
Properties
- Boiling point (1 atm)23.7°C / 74.7°F
- Critical point388.2°F at 623 PSIG
- Molar mass137.37 g/mol
- Temperature glideNegligible (0.00°F)
- ODP1
- GWP (AR5, 100-yr)4750
- GWP (AR6, 100-yr)5560
- Atmospheric lifetime45 years
What is R-11?
R-11 is pure trichlorofluoromethane — a chlorofluorocarbon developed in the 1930s alongside R-12. R-11's three chlorine atoms made it the most ozone-depleting of common refrigerants; the ODP measurement scale uses R-11 = 1.0 as its reference, with all other refrigerants' ozone-depletion potentials normalized to R-11.
R-11 was the dominant low-pressure centrifugal chiller refrigerant from the 1930s through the early 1990s. The Montreal Protocol CFC phase-out ended US production January 1, 1996. R-11 was replaced by R-123 (HCFC, lower ODP) in the late 1990s; R-123 production in turn ended in 2020, and the modern low-pressure chiller refrigerant is R-1233zd(E) (HCFO, near-zero GWP and ODP).
Where R-11 is used
- Reference for ODP measurement (R-11 = 1.0; all other refrigerants normalized to this)
- Historical low-pressure centrifugal chillers (essentially all replaced by now)
- Reference for refrigeration history and environmental policy education
Regulatory & phase-down status
R-11 production has been banned in the US since January 1, 1996 under the Montreal Protocol CFC phase-out. Reclaimed R-11 remains legal to use indefinitely for servicing pre-ban equipment, but the installed base is essentially gone — virtually all R-11 chillers have been replaced through end-of-life cycles since the ban.
Service notes
Mineral oil (MO) was the historical lubricant standard. R-11 operates at very low pressures (below atmospheric at typical chiller operating temperatures) — the saturation pressure at 70°F is -1.3 PSIG (vacuum). This is structural to the low-pressure centrifugal chiller design.
Operating cycle
Phase-down timeline
Global warming potential, in context
Low-pressure centrifugal chillers
Retrofit and replacement paths
Replacements for R-11
Frequently asked
›Why is R-11 the reference for ozone-depletion potential?
Convention. When the ODP concept was formalized in the 1970s, R-11 was the most-produced CFC refrigerant and was known to be a strong ozone depleter due to its three chlorine atoms. Setting R-11 = 1.0 as the reference gave a convenient scale for comparing other refrigerants. R-12's ODP is 1.0 (same as R-11); R-22's ODP is 0.055; HFC refrigerants have ODP 0 (no chlorine).
›Can I still get R-11?
Effectively no. Production was banned in 1996; the reclaimed supply pool has been drawn down by nearly 30 years of chiller replacement. Some R-11 may exist in laboratory or museum collections; for practical service work, R-11 systems must be either decommissioned or converted to a modern refrigerant — but conversion is rarely economic given the equipment age.
›What replaced R-11 in chillers?
R-123 (HCFC) replaced R-11 in the late 1990s — chemically similar but with much lower ODP (0.02 vs R-11's 1.0). R-123 production in turn ended in 2020 under the Montreal Protocol HCFC phase-out. The modern replacement is R-1233zd(E) (HCFO, Honeywell Solstice 1233zd) — near-zero ODP, GWP 1, ASHRAE A1 (easier machine-room requirements than R-123's B1 classification).
›Why does R-11 operate in vacuum?
Very low saturation pressures. R-11's normal boiling point is 23.7°C (74.7°F) — at most chiller operating temperatures the saturation pressure is below atmospheric. This is structural to the low-pressure centrifugal chiller design where R-11 was used; the equipment is physically large to handle the lower-density vapor, and continuous purge units are required to evacuate air that leaks INTO the system.
›Is R-11 still legal to use?
Reclaimed R-11 in pre-ban equipment is legal to use indefinitely under current US regulations. Production and import of new R-11 has been illegal since 1996. In practice the issue is moot — the supply is essentially exhausted and the equipment is at end of life.