R-134a PT chart

R-134a is a single-component HFC used in chillers, refrigeration and vehicle air conditioning. It runs at much lower pressures than R-410A or R-32.

Gauge pressures at sea level (14.696 psia). At altitude a gauge reads higher for the same temperature — use the PT calculator with your elevation. Generated with CoolProp 8.0.0 on 2026-10-25; how it was checked.

R-134a saturation pressure by temperature, gauge pressure at sea level
°F	°C	psig	kPa gauge
−40	−40.0	−7.3	−50
−39	−39.4	−7.0	−49
−38	−38.9	−6.8	−47
−37	−38.3	−6.6	−45
−36	−37.8	−6.4	−44
−35	−37.2	−6.1	−42
−34	−36.7	−5.9	−40
−33	−36.1	−5.6	−39
−32	−35.6	−5.4	−37
−31	−35.0	−5.1	−35
−30	−34.4	−4.8	−33
−29	−33.9	−4.6	−31
−28	−33.3	−4.3	−29
−27	−32.8	−4.0	−28
−26	−32.2	−3.7	−25
−25	−31.7	−3.4	−23
−24	−31.1	−3.1	−21
−23	−30.6	−2.8	−19
−22	−30.0	−2.5	−17
−21	−29.4	−2.1	−15
−20	−28.9	−1.8	−12
−19	−28.3	−1.5	−10
−18	−27.8	−1.1	−8
−17	−27.2	−0.8	−5
−16	−26.7	−0.4	−3
−15	−26.1	−0.0	−0
−14	−25.6	0.4	2
−13	−25.0	0.7	5
−12	−24.4	1.1	8
−11	−23.9	1.5	11
−10	−23.3	1.9	13
−9	−22.8	2.4	16
−8	−22.2	2.8	19
−7	−21.7	3.2	22
−6	−21.1	3.6	25
−5	−20.6	4.1	28
−4	−20.0	4.6	31
−3	−19.4	5.0	35
−2	−18.9	5.5	38
−1	−18.3	6.0	41
0	−17.8	6.5	45
1	−17.2	7.0	48
2	−16.7	7.5	52
3	−16.1	8.0	55
4	−15.6	8.5	59
5	−15.0	9.1	63
6	−14.4	9.6	66
7	−13.9	10.2	70
8	−13.3	10.8	74
9	−12.8	11.3	78
10	−12.2	11.9	82
11	−11.7	12.5	86
12	−11.1	13.1	91
13	−10.6	13.8	95
14	−10.0	14.4	99
15	−9.4	15.0	104
16	−8.9	15.7	108
17	−8.3	16.4	113
18	−7.8	17.0	117
19	−7.2	17.7	122
20	−6.7	18.4	127
21	−6.1	19.1	132
22	−5.6	19.9	137
23	−5.0	20.6	142
24	−4.4	21.3	147
25	−3.9	22.1	152
26	−3.3	22.9	158
27	−2.8	23.7	163
28	−2.2	24.5	169
29	−1.7	25.3	174
30	−1.1	26.1	180
31	−0.6	26.9	186
32	0.0	27.8	191
33	0.6	28.6	197
34	1.1	29.5	203
35	1.7	30.4	210
36	2.2	31.3	216
37	2.8	32.2	222
38	3.3	33.1	229
39	3.9	34.1	235
40	4.4	35.0	242
41	5.0	36.0	248
42	5.6	37.0	255
43	6.1	38.0	262
44	6.7	39.0	269
45	7.2	40.1	276
46	7.8	41.1	283
47	8.3	42.2	291
48	8.9	43.2	298
49	9.4	44.3	306
50	10.0	45.4	313
51	10.6	46.6	321
52	11.1	47.7	329
53	11.7	48.9	337
54	12.2	50.0	345
55	12.8	51.2	353
56	13.3	52.4	361
57	13.9	53.6	370
58	14.4	54.9	378
59	15.0	56.1	387
60	15.6	57.4	396
61	16.1	58.7	405
62	16.7	60.0	414
63	17.2	61.3	423
64	17.8	62.7	432
65	18.3	64.0	441
66	18.9	65.4	451
67	19.4	66.8	461
68	20.0	68.2	470
69	20.6	69.7	480
70	21.1	71.1	490
71	21.7	72.6	500
72	22.2	74.1	511
73	22.8	75.6	521
74	23.3	77.1	532
75	23.9	78.7	542
76	24.4	80.2	553
77	25.0	81.8	564
78	25.6	83.4	575
79	26.1	85.0	586
80	26.7	86.7	598
81	27.2	88.4	609
82	27.8	90.0	621
83	28.3	91.8	633
84	28.9	93.5	645
85	29.4	95.2	657
86	30.0	97.0	669
87	30.6	98.8	681
88	31.1	100.6	694
89	31.7	102.5	706
90	32.2	104.3	719
91	32.8	106.2	732
92	33.3	108.1	745
93	33.9	110.0	759
94	34.4	112.0	772
95	35.0	114.0	786
96	35.6	115.9	799
97	36.1	118.0	813
98	36.7	120.0	827
99	37.2	122.1	842
100	37.8	124.2	856
101	38.3	126.3	871
102	38.9	128.4	885
103	39.4	130.6	900
104	40.0	132.7	915
105	40.6	135.0	930
106	41.1	137.2	946
107	41.7	139.5	961
108	42.2	141.7	977
109	42.8	144.0	993
110	43.3	146.4	1009
111	43.9	148.7	1026
112	44.4	151.1	1042
113	45.0	153.5	1059
114	45.6	156.0	1075
115	46.1	158.4	1092
116	46.7	160.9	1110
117	47.2	163.5	1127
118	47.8	166.0	1144
119	48.3	168.6	1162
120	48.9	171.2	1180
121	49.4	173.8	1198
122	50.0	176.5	1217
123	50.6	179.1	1235
124	51.1	181.8	1254
125	51.7	184.6	1273
126	52.2	187.4	1292
127	52.8	190.2	1311
128	53.3	193.0	1331
129	53.9	195.8	1350
130	54.4	198.7	1370
131	55.0	201.6	1390
132	55.6	204.6	1410
133	56.1	207.5	1431
134	56.7	210.6	1452
135	57.2	213.6	1473
136	57.8	216.7	1494
137	58.3	219.7	1515
138	58.9	222.9	1537
139	59.4	226.0	1558
140	60.0	229.2	1580
141	60.6	232.4	1603
142	61.1	235.7	1625
143	61.7	239.0	1648
144	62.2	242.3	1671
145	62.8	245.7	1694
146	63.3	249.0	1717
147	63.9	252.5	1741
148	64.4	255.9	1764
149	65.0	259.4	1788
150	65.6	262.9	1813

Reading the chart

Each row is the pressure at which R-134a boils or condenses at that temperature. A negative gauge pressure is a vacuum.
R-134a is a single-component refrigerant, so liquid and vapor saturate at the same pressure.
To work out superheat or subcooling from your readings, use the Superheat and Subcooling Calculator.
Charge equipment to the manufacturer’s procedure and targets. Only certified technicians may handle refrigerant.