R-22 pressure-temperature chart

Gauge pressure at sea level. R-22 is a single-component refrigerant, so liquid and vapor saturate at the same pressure.

°F and psig°C and kPa

R-22 saturation pressure by temperature, °F and psig
°F	psig
-40	0.6
-39	1.0
-38	1.4
-37	1.8
-36	2.2
-35	2.6
-34	3.1
-33	3.5
-32	4.0
-31	4.5
-30	4.9
-29	5.4
-28	5.9
-27	6.4
-26	6.9
-25	7.4
-24	8.0
-23	8.5
-22	9.1
-21	9.6
-20	10.2
-19	10.8
-18	11.4
-17	12.0
-16	12.6
-15	13.2
-14	13.9
-13	14.5
-12	15.2
-11	15.9
-10	16.5
-9	17.2
-8	17.9
-7	18.7
-6	19.4
-5	20.1
-4	20.9
-3	21.7
-2	22.4
-1	23.2
0	24.0
1	24.9
2	25.7
3	26.5
4	27.4
5	28.3
6	29.2
7	30.1
8	31.0
9	31.9
10	32.8
11	33.8
12	34.8
13	35.8
14	36.8
15	37.8
16	38.8
17	39.9
18	40.9
19	42.0
20	43.1
21	44.2
22	45.3
23	46.5
24	47.6
25	48.8
26	50.0
27	51.2
28	52.4
29	53.7
30	55.0
31	56.2
32	57.5
33	58.8
34	60.2
35	61.5
36	62.9
37	64.3
38	65.7
39	67.1
40	68.6
41	70.0
42	71.5
43	73.0
44	74.5
45	76.1
46	77.6
47	79.2
48	80.8
49	82.4
50	84.1
51	85.7
52	87.4
53	89.1
54	90.8
55	92.6
56	94.4
57	96.1
58	98.0
59	99.8
60	101.6
61	103.5
62	105.4
63	107.3
64	109.3
65	111.2
66	113.2
67	115.3
68	117.3
69	119.4
70	121.4
71	123.5
72	125.7
73	127.8
74	130.0
75	132.2
76	134.5
77	136.7
78	139.0
79	141.3
80	143.6
81	146.0
82	148.4
83	150.8
84	153.2
85	155.7
86	158.2
87	160.7
88	163.2
89	165.8
90	168.4
91	171.0
92	173.7
93	176.4
94	179.1
95	181.8
96	184.6
97	187.4
98	190.2
99	193.0
100	195.9
101	198.8
102	201.8
103	204.7
104	207.7
105	210.8
106	213.8
107	216.9
108	220.0
109	223.2
110	226.4
111	229.6
112	232.8
113	236.1
114	239.4
115	242.8
116	246.1
117	249.5
118	253.0
119	256.4
120	260.0
121	263.5
122	267.1
123	270.7
124	274.3
125	278.0
126	281.7
127	285.4
128	289.2
129	293.0
130	296.9
131	300.8
132	304.7
133	308.6
134	312.6
135	316.7
136	320.7
137	324.8
138	329.0
139	333.2
140	337.4
141	341.6
142	345.9
143	350.3
144	354.6
145	359.0
146	363.5
147	368.0
148	372.5
149	377.1
150	381.7

R-22 saturation pressure by temperature, °C and kPa
°C	kPa
-40	4
-39	9
-38	14
-37	19
-36	25
-35	31
-34	37
-33	43
-32	49
-31	56
-30	63
-29	70
-28	77
-27	84
-26	92
-25	100
-24	108
-23	117
-22	126
-21	135
-20	144
-19	154
-18	163
-17	174
-16	184
-15	195
-14	206
-13	217
-12	229
-11	241
-10	253
-9	266
-8	279
-7	293
-6	306
-5	320
-4	335
-3	350
-2	365
-1	381
0	397
1	413
2	430
3	447
4	465
5	483
6	501
7	520
8	540
9	559
10	580
11	600
12	622
13	643
14	665
15	688
16	711
17	735
18	759
19	784
20	809
21	834
22	861
23	887
24	915
25	943
26	971
27	1,000
28	1,030
29	1,060
30	1,091
31	1,122
32	1,154
33	1,186
34	1,220
35	1,253
36	1,288
37	1,323
38	1,359
39	1,395
40	1,432
41	1,470
42	1,508
43	1,548
44	1,587
45	1,628
46	1,669
47	1,711
48	1,754
49	1,797
50	1,841
51	1,886
52	1,932
53	1,978
54	2,026
55	2,074
56	2,123
57	2,172
58	2,223
59	2,274
60	2,326
61	2,379
62	2,433
63	2,488
64	2,543
65	2,600

You're free to reuse this chart's numbers under CC BY 4.0. Just credit Pocket HVAC and link back to this page.

From pockethvac.com/r22-pt-chart/. Each row is solved at its exact temperature with CoolProp 8.0.0. Free to reuse under CC BY 4.0.

What is an R-22 PT chart?

An R-22 PT chart lists the pressure R-22 boils and condenses at for each temperature. At 40°F that's 68.6 psig, a lot lower than the 118.4 psig of the R-410A that replaced it. R-22 is a single-component refrigerant, so there's one pressure for each temperature, and you'll see it on cylinders as Freon 22 or Forane 22.

Anywhere liquid and vapor are together in a system, like inside the evaporator and condenser coils, the pressure and temperature are locked together, so one tells you the other. On the job, the chart turns gauge readings into saturation temperatures: the suction pressure gives the temperature the evaporator is boiling at, and the liquid line pressure gives the temperature the condenser is condensing at. Compare those with your line temperatures and you have superheat and subcooling.

R-22 was the standard refrigerant in home air conditioners and heat pumps for decades. It damages the ozone layer, so it was phased out: it hasn't been made in or imported into the US since 2020, and systems still running on it are serviced with recovered and reclaimed R-22.

How it's calculated

Absolute pressure = gauge pressure + 14.696 psi (101.325 kPa, one standard atmosphere)
Saturation data: R-22: CoolProp 8.0.0, R22
Between table points (every 0.5 °C): ln(pressure) is interpolated linearly in 1 ÷ absolute temperature
Printed chart rows are solved by CoolProp at each exact temperature

Sources

If a number doesn't match your chart, email me what you entered and what you expected, and I'll check it against the source. You can also read how the numbers are checked.

Checked by Paul Williams · Updated October 31, 2026

Questions

What is the R-22 pressure at 40°F?

R-22's saturation pressure at 40°F is 68.6 psig. At 100°F it's 195.9 psig.

When does R-22 go into a vacuum?

Below about -41.5°F its saturation pressure drops under atmospheric, so a gauge reads a vacuum. The chart above starts at -40°F, but the lookup goes down to about -60°F and shows those pressures in inches of mercury.

How accurate is this chart?

It comes from the NIST equation of state for R-22 through CoolProp, and matches NIST's own tables to within 0.01 psi.

R-22 PT Chart