RefrigerantASHRAE R-1233zd(E)

R1233zd(E) PT Chart

Q: Is R-1233zd(E) flammable?

No — ASHRAE class A1 (non-toxic, non-flammable). This is a primary advantage over R-1234ze (A2L) for chiller applications where A1 safety simplifies equipment-room and code compliance.

Q: What lubricant does R-1233zd(E) use?

POE oil typically. Verify against equipment OEM service literature. Some chiller OEMs may specify specific viscosity grades or alternative synthetic oils for particular compressor designs.

Q: What is Solstice zd?

Honeywell's trade name for R-1233zd(E). Honeywell is the primary commercial manufacturer; the refrigerant is supplied to multiple chiller OEMs for new equipment and retrofit applications.

Updated October 12, 2026

R-1233zd(E)

A1 Lower toxicity, no flame propagationHCFO

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^{[8], section 4.8}. Label: R-1233zd(E), safety class A1, GWP 4. No red band: AHRI Guideline N-2017 reserves it for flammable refrigerants^{[8], section 4.7}.

CF3CH=CHCl (E isomer)

Hydrochlorofluoroolefin (HCFO) — A1 non-flammable, GWP 4, near-zero ODP. The low-pressure replacement for R-123 in centrifugal chillers. Honeywell Solstice zd; very low operating pressures (sub-atmospheric on chiller evaporator).

R-1233zd(E) saturation pressure is 12.7 in. Hg vacuum at 40°F, 1.6 PSIG at 70°F, and 14.4 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

1.6 PSIG

GWP (100-yr)

4 US EPA value, 40 CFR 84.64(b)

Boiling point

64.9°F

Sourced facts

ASHRAE safety class: A1^[1]
Chemical formula: CF₃CH=CHCl (E)^[1]
GWP (100-yr): 4
ODP: 0.00034
Normal boiling point: 64.9°F (18.3°C)^[3]
Lubricant: POE
Trade name: Solstice zd^[7]

R-1233zd(E) PT calculator Superheat

R-1233zd(E) PT chart — printable saturation table

Looking for the R-1233zd(E) 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-1233zd(E) PT Chart — Pressure-Temperature Saturation Table

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

R-1233zd(E) · 1° increments · °F / PSIG

Tinted rows: NBP atmospheric crossover · 32°F H₂O freeze

R-1233zd(E) pressure-temperature saturation table in Fahrenheit and PSIG
Temp (°F)	Pressure (PSIG)
−40°F	28.2 in. Hg vac.
−39°F	28.2 in. Hg vac.
−38°F	28.1 in. Hg vac.
−37°F	28.0 in. Hg vac.
−36°F	28.0 in. Hg vac.
−35°F	27.9 in. Hg vac.
−34°F	27.8 in. Hg vac.
−33°F	27.8 in. Hg vac.
−32°F	27.7 in. Hg vac.
−31°F	27.6 in. Hg vac.
−30°F	27.5 in. Hg vac.
−29°F	27.5 in. Hg vac.
−28°F	27.4 in. Hg vac.
−27°F	27.3 in. Hg vac.
−26°F	27.2 in. Hg vac.
−25°F	27.1 in. Hg vac.
−24°F	27.0 in. Hg vac.
−23°F	26.9 in. Hg vac.
−22°F	26.8 in. Hg vac.
−21°F	26.7 in. Hg vac.
−20°F	26.6 in. Hg vac.
−19°F	26.5 in. Hg vac.
−18°F	26.4 in. Hg vac.
−17°F	26.3 in. Hg vac.
−16°F	26.2 in. Hg vac.
−15°F	26.0 in. Hg vac.
−14°F	25.9 in. Hg vac.
−13°F	25.8 in. Hg vac.
−12°F	25.7 in. Hg vac.
−11°F	25.5 in. Hg vac.
−10°F	25.4 in. Hg vac.
−9°F	25.3 in. Hg vac.
−8°F	25.1 in. Hg vac.
−7°F	25.0 in. Hg vac.
−6°F	24.8 in. Hg vac.
−5°F	24.7 in. Hg vac.
−4°F	24.5 in. Hg vac.
−3°F	24.3 in. Hg vac.
−2°F	24.2 in. Hg vac.
−1°F	24.0 in. Hg vac.
0°F	23.8 in. Hg vac.
1°F	23.7 in. Hg vac.
2°F	23.5 in. Hg vac.
3°F	23.3 in. Hg vac.
4°F	23.1 in. Hg vac.
5°F	22.9 in. Hg vac.
6°F	22.7 in. Hg vac.
7°F	22.5 in. Hg vac.
8°F	22.3 in. Hg vac.
9°F	22.1 in. Hg vac.
10°F	21.9 in. Hg vac.
11°F	21.7 in. Hg vac.
12°F	21.4 in. Hg vac.
13°F	21.2 in. Hg vac.
14°F	21.0 in. Hg vac.
15°F	20.7 in. Hg vac.
16°F	20.5 in. Hg vac.
17°F	20.2 in. Hg vac.
18°F	20.0 in. Hg vac.
19°F	19.7 in. Hg vac.
20°F	19.4 in. Hg vac.
21°F	19.1 in. Hg vac.
22°F	18.9 in. Hg vac.
23°F	18.6 in. Hg vac.
24°F	18.3 in. Hg vac.
25°F	18.0 in. Hg vac.
26°F	17.7 in. Hg vac.
27°F	17.4 in. Hg vac.
28°F	17.1 in. Hg vac.
29°F	16.7 in. Hg vac.
30°F	16.4 in. Hg vac.
31°F	16.1 in. Hg vac.
32°F H₂O freeze	15.7 in. Hg vac.
33°F	15.4 in. Hg vac.
34°F	15.0 in. Hg vac.
35°F	14.6 in. Hg vac.
36°F	14.3 in. Hg vac.
37°F	13.9 in. Hg vac.
38°F	13.5 in. Hg vac.
39°F	13.1 in. Hg vac.
40°F	12.7 in. Hg vac.
41°F	12.3 in. Hg vac.
42°F	11.9 in. Hg vac.
43°F	11.5 in. Hg vac.
44°F	11.0 in. Hg vac.
45°F	10.6 in. Hg vac.
46°F	10.1 in. Hg vac.
47°F	9.7 in. Hg vac.
48°F	9.2 in. Hg vac.
49°F	8.7 in. Hg vac.
50°F	8.3 in. Hg vac.
51°F	7.8 in. Hg vac.
52°F	7.3 in. Hg vac.
53°F	6.8 in. Hg vac.
54°F	6.2 in. Hg vac.
55°F	5.7 in. Hg vac.
56°F	5.2 in. Hg vac.
57°F	4.6 in. Hg vac.
58°F	4.1 in. Hg vac.
59°F	3.5 in. Hg vac.
60°F	2.9 in. Hg vac.
61°F	2.4 in. Hg vac.
62°F	1.8 in. Hg vac.
63°F	1.2 in. Hg vac.
64°F	0.5 in. Hg vac.
65°F NBP (atmospheric)	0.0
66°F	0.4
67°F	0.7
68°F	1.0
69°F	1.3
70°F	1.6
71°F	2.0
72°F	2.3
73°F	2.7
74°F	3.0
75°F	3.4
76°F	3.8
77°F	4.1
78°F	4.5
79°F	4.9
80°F	5.3
81°F	5.7
82°F	6.1
83°F	6.5
84°F	6.9
85°F	7.3
86°F	7.7
87°F	8.2
88°F	8.6
89°F	9.1
90°F	9.5
91°F	10.0
92°F	10.4
93°F	10.9
94°F	11.4
95°F	11.9
96°F	12.4
97°F	12.9
98°F	13.4
99°F	13.9
100°F	14.4
101°F	14.9
102°F	15.5
103°F	16.0
104°F	16.6
105°F	17.1
106°F	17.7
107°F	18.3
108°F	18.8
109°F	19.4
110°F	20.0
111°F	20.6
112°F	21.3
113°F	21.9
114°F	22.5
115°F	23.1
116°F	23.8
117°F	24.4
118°F	25.1
119°F	25.8
120°F	26.5
121°F	27.1
122°F	27.8
123°F	28.6
124°F	29.3
125°F	30.0
126°F	30.7
127°F	31.5
128°F	32.2
129°F	33.0
130°F	33.8
131°F	34.5
132°F	35.3
133°F	36.1
134°F	36.9
135°F	37.8
136°F	38.6
137°F	39.4
138°F	40.3
139°F	41.1
140°F	42.0
141°F	42.9
142°F	43.8
143°F	44.7
144°F	45.6
145°F	46.5
146°F	47.4
147°F	48.4
148°F	49.3
149°F	50.3
150°F	51.3

R-1233zd(E) pressure-temperature saturation table in Celsius and kPa
Temp (°C)	Pressure (kPa)
−40°C	−96
−39°C	−95
−38°C	−95
−37°C	−94
−36°C	−94
−35°C	−94
−34°C	−93
−33°C	−93
−32°C	−92
−31°C	−91
−30°C	−91
−29°C	−90
−28°C	−90
−27°C	−89
−26°C	−88
−25°C	−87
−24°C	−87
−23°C	−86
−22°C	−85
−21°C	−84
−20°C	−83
−19°C	−82
−18°C	−81
−17°C	−80
−16°C	−79
−15°C	−78
−14°C	−76
−13°C	−75
−12°C	−74
−11°C	−72
−10°C	−71
−9°C	−69
−8°C	−68
−7°C	−66
−6°C	−65
−5°C	−63
−4°C	−61
−3°C	−59
−2°C	−57
−1°C	−55
0°C H₂O freeze	−53
1°C	−51
2°C	−49
3°C	−47
4°C	−44
5°C	−42
6°C	−39
7°C	−36
8°C	−34
9°C	−31
10°C	−28
11°C	−25
12°C	−22
13°C	−19
14°C	−15
15°C	−12
16°C	−8
17°C	−5
18°C NBP (atmospheric)	−1
19°C	3
20°C	7
21°C	11
22°C	15
23°C	19
24°C	24
25°C	28
26°C	33
27°C	38
28°C	43
29°C	48
30°C	53
31°C	59
32°C	64
33°C	70
34°C	76
35°C	82
36°C	88
37°C	94
38°C	101
39°C	107
40°C	114
41°C	121
42°C	128
43°C	136
44°C	143
45°C	151
46°C	159
47°C	167
48°C	175
49°C	183
50°C	192
51°C	201
52°C	210
53°C	219
54°C	228
55°C	238
56°C	248
57°C	258
58°C	268
59°C	279
60°C	290
61°C	301
62°C	312
63°C	323
64°C	335
65°C	347
66°C	359

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-1233zd(E) PT chart data: CoolProp 7.2.0 (published Helmholtz equations of state / mixture models — see the source citations above).

Lower toxicity, no flame propagation

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^{[1], safety group definitions and refrigerant safety classifications}. See full reference.

Saturation pressure-temperature curve

Pressure

Temperature

Highlight at°F

Quick lookup — R-1233zd(E)

Temp:°F

1.6PSIG(11 kPa)

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

Common service temperatures

32°F

−8PSIG

Freezing

45°F

−5PSIG

Heat-pump heat

70°F

2PSIG

Standard

75°F

3PSIG

Test ref

80°F

5PSIG

Warm

95°F

12PSIG

Summer peak

Saturation values from CoolProp 7.2.0^[3]. Operating pressure on a running system differs — see the operating-pressure references for in-use values.

At a glance

Chemistry

CF3CH=CHCl (E isomer)

(E)-1-Chloro-3,3,3-trifluoro-1-propene

Lubricant compatibility

POEPVEMO

Low-pressure HCFO with very low GWP and short atmospheric lifetime. Engineered as a long-term R-123 replacement.

Trade names

Solstice 1233zd — Honeywell
Solstice LBA — Honeywell

Common applications

Low-pressure centrifugal chillers
Foam blowing agent (polyurethane insulation)
Organic Rankine cycle working fluid

Properties

Boiling point (1 atm)
64.9°F (18.3°C)
Critical point
331.6°F (166.5°C) at 511 PSIG
Molar mass
130.49 g/mol
ODP
0.00034
GWP (100-yr)
4 US EPA value, 40 CFR 84.64(b) IPCC: AR4 not assessed · AR5 1 · AR6 3.88
Atmospheric lifetime
0.07 years
New-equipment status (US)
Not an AIM Act regulated substance; 40 CFR 84.54 GWP limits don't apply.

What is R-1233zd(E)?

R-1233zd(E) is a hydrochlorofluoroolefin (HCFO) — chemically related to HFOs but with one chlorine atom in the molecular structure. The compound is trans-1-chloro-3,3,3-trifluoro-1-propene^[1]. The single chlorine gives R-1233zd(E) very small but non-zero ozone-depletion potential (0.00034) — far below R-22's 0.055 and far below the substances the Montreal Protocol controls. R-1233zd(E) is not itself a controlled substance under the Protocol, though its ODP is technically not zero.

R-1233zd(E) was developed by Honeywell as a replacement for R-123 in low-pressure centrifugal chillers. The pressure envelope closely matches R-123; the safety class (A1) is preserved; the GWP (4) is dramatically lower than R-123's 77.

Where R-1233zd(E) is used

Low-pressure centrifugal chiller R-123 replacement (Trane, others)
New low-pressure chiller equipment installations
High-temperature heat pumps (some applications)
Foam blowing agent in polyurethane insulation

Regulatory & phase-down status

R-1233zd(E) is not a controlled substance under the Montreal Protocol; its ODP (0.00034) is far below the substances the Protocol regulates and it is treated as effectively zero-ODP for practical purposes^[5]. GWP 4 places it below every regulatory threshold.

R-1233zd(E) faces no meaningful phase-down pressure under EU F-Gas, AIM Act, or Montreal Protocol HCFC schedules.

Service notes

POE oil typical for chiller applications^[6]. Verify against equipment OEM service literature for specific viscosity grade. A1 classification means no A2L procedures required.

R-1233zd(E) operates at very low pressures — sub-atmospheric on the evaporator side at typical chilled-water temperatures. Equipment is designed for sub-atmospheric operation with purge units to remove non-condensable atmospheric contamination.

Operating cycle

Phase-down timeline

R-1233zd(E) 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

Low-pressure centrifugal chillers

Retrofit and replacement paths

R-1233zd(E) replaces

Reading the R-1233zd(E) PT chart — sub-atmospheric operation on the low side

R-1233zd(E)'s PT chart shows very low pressures across the chiller operating range. At typical chiller evaporator temperatures (35-45°F), saturation is well below atmospheric pressure — the chiller evaporator runs at vacuum.

Single saturation curve (pure refrigerant, no glide). Standard 500 PSI manifold gauges have more than enough range; the operational concern is at the low end, where vacuum-rated gauges and procedures are needed.

Sub-atmospheric operation requires purge units

Low-pressure centrifugal chillers operating below atmospheric pressure on the evaporator face air ingress through any leak path. The chillers include purge units to remove non-condensable atmospheric contamination that accumulates over time. This is a normal feature of low-pressure chiller operation, not a fault — but service technicians need to understand the purge-unit role and operation.

R-1233zd(E) vs R-123, R-11: saturation pressure

Saturation pressure (PSIG, gauge) for R-1233zd(E) vs R-123, R-11. Each column shows the percent difference from R-1233zd(E). Source: CoolProp 7.2.0 dataset.
Temp	R-1233zd(E)	R-123	R-11
0°F	23.8 in. Hg vac.	25.9 in. Hg vac.	24.7 in. Hg vac.
40°F	12.7 in. Hg vac.	18.2 in. Hg vac.	15.6 in. Hg vac.
70°F	1.6	6.6 in. Hg vac.	2.7 in. Hg vac.
100°F	14.4	6.1(−58%)	8.9(−38%)

Frequently asked

›What is R-1233zd(E) used for?

Low-pressure centrifugal chiller R-123 replacement primarily. Trane offers R-1233zd(E) chillers (CenTraVac product line); other chiller OEMs also offer R-1233zd(E) options. Honeywell markets the refrigerant as Solstice zd^[7].

›Why is R-1233zd(E) called HCFO instead of HFO?

HCFO = hydrochlorofluoroolefin. The "C" denotes the one chlorine atom in the molecule. R-1233zd(E)'s structure is CF₃CH=CHCl — three fluorines, one chlorine, plus hydrogen and the carbon-carbon double bond. HFOs (hydrofluoroolefins) have no chlorine; R-1234yf and R-1234ze are HFOs. The chlorine atom in R-1233zd(E) gives it the very small ODP (0.00034) that HFOs don't have.

›What's R-1233zd(E)'s GWP?

4 on the US EPA basis (40 CFR 84.64); the strict IPCC AR5 value is 1^[2]. Either way it's very low — the 26-day atmospheric lifetime drives it. R-1233zd(E) sits alongside R-744 (CO₂) as one of the lowest-GWP commercial refrigerants.

›Is R-1233zd(E) ozone-depleting?

Technically yes — ODP 0.00034 — but R-1233zd(E) is not a controlled substance under the Montreal Protocol, and its ODP is far below the substances the Protocol regulates. For practical purposes R-1233zd(E) is treated as zero-ODP. EPA SNAP lists R-1233zd(E) as acceptable for new centrifugal chillers^[4].

›Is R-1233zd(E) flammable?

No — ASHRAE class A1 (non-toxic, non-flammable)^[1]. This is a primary advantage over R-1234ze (A2L) for chiller applications where A1 safety simplifies equipment-room and code compliance.

›What lubricant does R-1233zd(E) use?

POE oil typically^[6]. Verify against equipment OEM service literature. Some chiller OEMs may specify specific viscosity grades or alternative synthetic oils for particular compressor designs.

›What is Solstice zd?

Honeywell's trade name for R-1233zd(E)^[7]. Honeywell is the primary commercial manufacturer; the refrigerant is supplied to multiple chiller OEMs for new equipment and retrofit applications.

Download this dataset

Full PT chart for R-1233zd(E) · CC BY 4.0 · attribute the source

CSV JSON

Sources & citations

[1]
ANSI/ASHRAE Standard 34-2022, Designation and Safety Classification of Refrigerants (free read-only version). ASHRAE. 2022. https://www.ashrae.org/technical-resources/standards-and-guidelines/read-only-versions-of-ashrae-standards (accessed October 2, 2026)
[2]
IPCC AR5 WG1 (2013), Chapter 8, Appendix 8.A, Table 8.A.1. IPCC AR5 Working Group I. 2013. https://www.ipcc.ch/report/ar5/wg1/ (accessed October 2, 2026)
[3]
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
[4]
EPA SNAP — R-1233zd(E) acceptable in new centrifugal chillers. US EPA (SNAP). https://www.epa.gov/snap (accessed October 2, 2026)
[5]
Montreal Protocol on Substances that Deplete the Ozone Layer. UNEP Ozone Secretariat. https://ozone.unep.org/treaties/montreal-protocol (accessed October 2, 2026)
[6]
AHRI Standard 700-2019. 2019. https://www.ahrinet.org/search-standards
[7]
Honeywell Solstice zd (R-1233zd(E)) Technical Information. Honeywell. https://www.honeywell-refrigerants.com/americas/ (accessed October 2, 2026)
[8]
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)