Mainline heat pumps

89 ENERGY STAR certified Mainline outdoor units (49 mini-split, 36 central, 4 packaged). The most efficient is the ML06HP230CALH-O at 35.0 SEER2 and 15.6 HSPF2; 79 models are rated for cold climates.

Some of these units are also certified under Comfort-Aire, KERR, Kerr Kapstone, Century, Midea, MRCOOL, Blueridge, Innovair.

ENERGY STAR data, updated October 12, 2026

89 models, ranked by SEER2 (cooling efficiency), then HSPF2.

#		Type						Cold
1	Mainline ML06HP230CALH-OML Series	Mini-split	6,000 BTU	35.0	17.4	15.6	13,500	Yes	2
2	Mainline ML09HP230CALH-OML Series	Mini-split	9,000 BTU	33.3	17.0	14.6	13,500	Yes	2
3	Mainline ML12HP230CALH-OML Series	Mini-split	12,000 BTU	29.4	14.2	12.7	13,500	Yes	2
4	Mainline ML09HP230NEXH-OML Series	Mini-split	9,000 BTU	27.2	15.1	13.8	11,900	Yes	12
5	Mainline ML09HP230NEX-OML Series	Mini-split	9,000 BTU	26.0	16.2	13.9	8,600	Yes	12
6	Mainline ML18HP230CALH-OML Series	Mini-split	18,000 BTU	25.6	15.0	-	22,600	Yes	2
7	Mainline ML06HP230NEXH-OML Series	Mini-split	6,000 BTU	25.3	16.0	14.6	8,100	Yes	6
8	Mainline ML18HP230MUL - OBMS Series	Mini-split	18,000 BTU	25.1	14.0	10.0	14,600	Yes	3
9	Mainline ML18HP230MUL-OM3O Series	Mini-split	18,000 BTU	25.1	14.0	10.0	14,600	Yes	6
10	Mainline ML12HP230NEXH-OML Series	Mini-split	12,000 BTU	25.0	12.5	11.6	12,000	Yes	12
11	Mainline ML18HP230MULH - OBMS Series	Mini-split	18,000 BTU	25.0	15.0	10.4	19,000	Yes	3
12	Mainline ML18HP230MULH-OM3O Series	Mini-split	18,000 BTU	25.0	15.0	10.4	19,000	Yes	6
13	Mainline ML27HP230MUL - OBMS Series	Mini-split	24,000 BTU	25.0	13.0	9.5	19,000	Yes	3
14	Mainline ML27HP230MUL-OM4O Series	Mini-split	24,000 BTU	25.0	13.0	9.5	19,000	Yes	6
15	Mainline ML12HP230NEX-OML Series	Mini-split	12,000 BTU	24.6	12.7	11.5	8,900	Yes	12
16	Mainline ML18HP230NEX-OML Series	Mini-split	18,000 BTU	24.0	13.5	13.5	14,200	Yes	16
17	Mainline ML48HP230MUL - OBMS Series	Mini-split	48,000 BTU	24.0	12.5	10.6	38,000	Yes	3
18	Mainline ML48HP230MUL-OM6O Series	Mini-split	42,000 BTU	24.0	12.5	10.6	38,000	Yes	6
19	Mainline ML36HP230MUL-OM5O Series	Mini-split	36,000 BTU	24.0	12.0	10.0	26,000	Yes	6
20	Mainline ML36HP230MUL - OBMS Series	Mini-split	36,000 BTU	24.0	12.0	9.5	26,000	Yes	3
21	Mainline ML24HP230NEX-OML Series	Mini-split	24,000 BTU	23.5	13.0	11.1	19,000	Yes	10
22	Mainline ML12HP115NEX-OML Series	Mini-split	12,000 BTU	23.2	12.5	10.4	7,300	No	2
23	Mainline ML36HP230MULH-OM5O Series	Mini-split	36,000 BTU	23.0	13.0	11.3	38,000	Yes	6
24	Mainline ML48HP230MULH - OBMS Series	Mini-split	48,000 BTU	23.0	12.0	11.0	48,000	Yes	3
25	Mainline ML48HP230MULH-OM6O Series	Mini-split	48,000 BTU	23.0	12.0	11.0	48,000	Yes	6
26	Mainline ML36HP230MULH - OBMS Series	Mini-split	36,000 BTU	23.0	13.0	10.7	38,000	Yes	3
27	Mainline ML27HP230MULH - OBMS Series	Mini-split	30,000 BTU	23.0	12.5	10.5	27,000	Yes	3
28	Mainline ML27HP230MULH-OM4O Series	Mini-split	30,000 BTU	23.0	12.5	10.5	27,000	Yes	6
29	Mainline ML15HP230NEXH-OML Series	Mini-split	15,000 BTU	22.7	14.0	10.2	18,000	Yes	1
30	Mainline ML24HP230NEXH-OML Series	Mini-split	24,000 BTU	22.3	12.5	13.3	24,200	Yes	10
31	Mainline ML55HP230MULH-OM6O Series	Mini-split	48,000 BTU	22.2	12.0	10.7	48,000	Yes	6
32	Mainline ML55HP230MULH - OMO Series	Mini-split	48,000 BTU	22.2	12.0	10.7	48,000	Yes	3
33	Mainline ML18HP230NEXH-OML Series	Mini-split	18,000 BTU	21.7	13.0	12.3	18,000	Yes	16
34	Mainline ML09HP115GEN-OML Series	Mini-split	9,000 BTU	21.5	12.5	9.0	6,500	Yes	2
35	Mainline ML12HP230GEN-OML Series	Mini-split	12,000 BTU	21.3	10.8	9.1	8,000	Yes	2
36	Mainline ML36HP230LCMH-OML Series	Mini-split	36,000 BTU	21.2	12.0	11.1	39,500	Yes	5
37	Mainline ML09HP230GEN-OML Series	Mini-split	9,000 BTU	21.2	12.6	9.1	7,000	Yes	2
38	Mainline ML24HP230CALH-OML Series	Mini-split	24,000 BTU	21.0	13.0	13.5	24,200	Yes	2
39	Mainline MLP19AY24AJVCElite	Central	2-ton	21.0	13.0	9.5	19,500	Yes	27
40	Mainline ML33HP230NEXH-OML Series	Mini-split	30,000 BTU	20.0	11.7	10.5	34,600	Yes	4
41	Mainline ML36HP230LCM-OML Series	Mini-split	36,000 BTU	20.0	9.6	10.3	26,600	Yes	2
42	Mainline MLP19AY36AJVCF Series	Central	3-ton	20.0	12.5	9.5	29,400	Yes	1
43	Mainline ML30HP230GEN-OML Series	Mini-split	30,000 BTU	20.0	11.0	9.2	20,400	Yes	3
44	Mainline ML48HP230LCM-OML Series	Mini-split	48,000 BTU	19.8	9.5	10.2	40,500	Yes	8
45	Mainline ML33HP230CALH-OML Series	Mini-split	30,000 BTU	19.5	12.0	10.5	35,000	Yes	2
46	Mainline ML18HP230LMNTH-OML Series	Central	1.5-ton	19.3	12.1	10.8	19,600	Yes	18
47	Mainline ML18HP230GEN-OML Series	Mini-split	18,000 BTU	19.2	10.8	9.6	11,500	Yes	2
48	Mainline MLP19AY48AJVCElite	Central	4-ton	19.0	12.0	10.0	42,000	No	14
49	Mainline ML09HP230WIN-OM5F Series	Mini-split	9,000 BTU	19.0	10.9	9.7	7,000	Yes	2
50	Mainline ML18HP230LMNT-OML Series	Central	1.5-ton	18.8	11.0	9.4	11,400	No	6
51	Mainline ML24HP230GEN-OMSAG Series	Mini-split	24,000 BTU	18.7	10.0	9.3	17,000	Yes	2
52	Mainline ML24HP230LMNTH-OML Series	Central	2-ton	18.6	12.0	10.5	21,600	Yes	20
53	Mainline ML30HP230LMNT-O37M Series	Central	2.5-ton	18.6	11.0	8.7	18,700	No	1
54	Mainline ML48HP230LCMH-OML Series	Mini-split	48,000 BTU	18.5	9.4	11.0	47,500	Yes	8
55	Mainline ML24HP230LMNT-OML Series	Central	2-ton	18.1	11.0	10.4	21,600	Yes	18
56	Mainline ML60HP230LCMH-OML Series	Mini-split	48,000 BTU	18.0	9.0	10.7	54,000	Yes	6
57	Mainline ML36HP230LMNTH-OML Series	Central	3-ton	18.0	12.0	10.3	39,000	Yes	22
58	Mainline ML33HP230LMNTH-OML Series	Central	3-ton	17.7	12.0	10.0	32,600	Yes	4
59	Mainline ML30HP230LMNTH-OML Series	Central	2.5-ton	17.5	11.7	10.8	33,200	Yes	21
60	Mainline ML48HP230LMNTH-OML Series	Central	4-ton	17.5	12.0	9.5	48,000	Yes	13
61	Mainline ML60HP230LMNTH-OML Series	Central	4-ton	17.5	12.0	9.5	54,000	Yes	10
62	Mainline ML24HP230WIN-OM5F Series	Mini-split	24,000 BTU	17.0	9.0	8.5	17,100	Yes	2
63	Mainline ML42HP230LMNTH-OML Series	Central	3.5-ton	16.7	11.7	9.5	46,000	Yes	2
64	Mainline ML36HP230LMNT-OML Series	Central	3-ton	16.7	10.2	9.3	29,200	Yes	6
65	Mainline ML50HP230LMNTH-OML Series	Central	4-ton	16.3	11.7	9.0	52,000	Yes	2
66	Mainline ML48HP230LMNT-OML Series	Central	4-ton	16.0	10.0	9.0	40,000	Yes	7
67	Mainline MLP15AZ30AJ2NF Series	Central	2.5-ton	16.0	11.7	8.1	16,100	Yes	10
68	Mainline MLP15AZ60AJ2NF Series	Central	5-ton	16.0	11.7	8.1	34,400	Yes	4
69	Mainline MLP15AY42AJ2NElite	Central	3.5-ton	16.0	11.7	8.1	19,300	Yes	58
70	Mainline MLP15AY48AJ2NElite	Central	4-ton	16.0	11.7	8.1	23,400	Yes	1
71	Mainline MLP15AZ18AJ2NElite	Central	1.5-ton	16.0	11.7	8.1	9,500	Yes	12
72	Mainline MLP15AZ24AJ2NCLASSIC PLUS/ACHIEVER PLUS	Central	2-ton	16.0	11.7	8.1	12,700	Yes	13
73	Mainline MPP15AY42AJ2NPerformance	Central	3.5-ton	16.0	11.7	8.1	19,300	Yes	53
74	Mainline MPP15AZ60AJ2NPerformance	Central	5-ton	16.0	11.7	8.1	30,600	Yes	1
75	Mainline ML60HP230LMNT-OML Series	Central	4-ton	15.2	8.6	8.4	38,000	Yes	2
76	Mainline MPP15AZ48AJ2NF-SERIES PLUS	Central	4-ton	15.2	11.7	8.1	24,200	Yes	1
77	Mainline MLP15AZ36AJ2NF Series	Central	3-ton	15.2	11.7	8.1	19,400	Yes	2
78	Mainline MLP15AZ42AJ2NF Series	Central	3.5-ton	15.2	11.7	8.1	22,800	Yes	2
79	Mainline MLP15AZ48AJ2NF Series	Central	4-ton	15.2	11.7	8.1	27,200	Yes	2
80	Mainline MLP15AY18AJ2NElite	Central	1.5-ton	15.2	11.7	8.1	8,600	Yes	1
81	Mainline MPP15AZ18AJ2NPerformance	Central	1.5-ton	15.2	11.7	8.1	9,500	Yes	7
82	Mainline MPP15AZ24AJ2NPerformance	Central	2-ton	15.2	11.7	8.1	12,700	Yes	8
83	Mainline MPP15AZ42AJ2NPerformance	Central	3.5-ton	15.2	11.7	8.1	20,400	Yes	1
84	Mainline MLP15AY36AJ2NElite	Central	3-ton	15.2	11.7	7.8	18,500	No	1
85	Mainline MPP15AZ36AJ2NPerformance	Central	3-ton	15.2	11.7	7.8	17,500	No	1
86	Mainline RHPXYC036AJTRHPXYC	Packaged	3-ton	15.2	11.5	7.2	13,800	No	7
87	Mainline RHPXYC048AJTRHPXYC	Packaged	4-ton	15.2	11.5	7.2	18,000	No	7
88	Mainline RHPXYC060AJTRHPXYC	Packaged	5-ton	15.2	11.5	7.2	25,000	No	7
89	Mainline RHPXYC024AJTRHPXYC	Packaged	2-ton	15.2	11.5	7.2	14,000	No	9