Against comparable models

Each cell is the share of same-size, same-type models that the manufacturer’s typical model beats (50% is typical); the higher score is in bold. Raw medians are underneath for context: they depend on which sizes each one makes, so they are not compared.

Innovair and ZERO on every ratingPeer scores, 0–100 · grey ticks: every ranked manufacturer · shaded: the middle half of each one’s modelsMeasured against models of the same size and duct type, Innovair scores higher on 6 of the 6 ratings.

Innovair
ZERO
Other ranked manufacturers

Source: AHRI Directory, NEEP · as of Oct 9, 2026

Average peer percentile, raw median and rank among ranked manufacturers
Rating	Innovair	ZERO
Efficiency index	58% (higher)median — · 8th ranked	53% (higher)median —
COP at 5°F	58% (higher)median 2.00 · 12th ranked	45% (higher)median 1.94
Capacity retention at 5°F	60% (higher)median 78% · 7th ranked	52% (higher)median 74%
HSPF2	61% (higher)median 9.5 · 8th ranked	57% (higher)median 9.5
SEER2	60% (higher)median 20.0 · 9th ranked	58% (higher)median 19.0
EER2	51% (higher)median 11.7 · 16th ranked	48% (higher)median 11.7
Heating capacity at 5°F	60% (higher)median 19,000 Btu/h · 9th ranked	55% (higher)median 18,750 Btu/h
Outdoor models	126	119
AHRI certifications	484	164

Share of models meeting each standard

Percent of each manufacturer’s models with a qualifying certification
Standard	Innovair	ZERO
CEE 2025 Tier 1 (Split ASHP)	82.5%104 models	70.6%84 models
CEE 2026 Tier 1 (Split ASHP)	80.2%101 models	69.7%83 models
CEE Advanced Tier (Split ASHP)	1.6%2 models	0%0 models
Xcel Energy Colorado cold-climate ASHP (2025)	78.6%99 models	64.7%77 models
DOE Cold Climate Heat Pump Challenge	1.6%2 models	0%0 models
ENERGY STAR Cold Climate	69%87 models	52.9%63 models

Sizes and duct types offered

Models in each peer group, with the efficiency index of those models against the rest of the group.

Side by side, inside each size and duct typeShape: every model of the group · bars: each manufacturer’s middle half, median dot, 10th–90th line · 10 groups where both have models

Innovair
ZERO
All models of the group

Raw ratings are only placed side by side within one size and duct type, where they are comparable.

Source: AHRI Directory · as of Oct 9, 2026

Models per peer group · efficiency index within the group
Size and duct type	Innovair	ZERO
Ducted, up to 1.5 tons	19 · index 70%	7 · index 68%
Ducted, 2 tons	11 · index 59%	13 · index 51%
Ducted, 2.5–3 tons	26 · index 62%	20 · index 54%
Ducted, 3.5–4.5 tons	23 · index 64%	26 · index 54%
Ducted, 5 tons and up	4 · index 63%	2 · index 64%
Non-ducted, up to 1.5 tons	48 · index 53%	39 · index 53%
Non-ducted, 2 tons	9 · index 52%	9 · index 50%
Non-ducted, 2.5–3 tons	20 · index 54%	13 · index 45%
Non-ducted, 3.5–4.5 tons	12 · index 52%	6 · index 52%
Non-ducted, 5 tons and up	2 · index 59%	2 · index 27%

Cold-climate and all-around picks, size class by size class

Each manufacturer’s best model on each board in every size and duct type, side by side; the higher score is in bold. Both scores are 0–100 against every model of that size class (the line on each bar is 50, the typical model there), so the two compare fairly even when they make different sizes.

Cold-climate picks

Best cold-climate pick per size and duct type (keeps at least 70% of its heat at 5°F). Qualifies when its capacity retention at 5°F (capacity at 5°F as a share of capacity at 47°F) is at least 70% and Capacity retention at 5°F, COP at 5°F, HSPF2 are all rated. Score = the equal-weight mean of its peer percentiles on Capacity retention at 5°F, COP at 5°F, HSPF2 (share of the other models in its peer group it beats, 0–100), all from one certified pairing: in each duct type a model is sold in, its qualifying pairing of that type with the best score; equal scores (one decimal) go to the higher heating capacity at 5°F.
Size and duct type	InnovairCold-climate score, best model	ZEROCold-climate score, best model
Ducted, up to 1.5 tons	86.7(50 is the typical model of its size class) (higher)SHV18H2BAwith ducted air handler SWV18BDA16 of 18 models qualify · AHRI 216027612	72.6(50 is the typical model of its size class)Z4SOV-18HDMB-USAlso listed as Z3SOV-18HDMB-US5 of 7 models qualify · AHRI 217138401
Ducted, 2 tons	85.7(50 is the typical model of its size class) (higher)MOS24H2BH0Awith ducted air handler MDH24H2MHWA10 of 12 models qualify · AHRI 215725473	70.4(50 is the typical model of its size class)ZRRV07HPBYFC-18SAlso listed as ZPRVO7HPBYFC-18S, ZPRV07HPBYFC-18S11 of 13 models qualify · AHRI 217904930
Ducted, 2.5–3 tons	83.2(50 is the typical model of its size class) (higher)MOS36H2BH0Awith ducted air handler MDH36H2MHWA22 of 26 models qualify · AHRI 215735335	82.5(50 is the typical model of its size class)Z4SOV-36HDMB-USHH13 of 20 models qualify · AHRI 217752806
Ducted, 3.5–4.5 tons	82.7(50 is the typical model of its size class)MOM48H2BH6AAlso listed as MOM48H2BH6B20 of 23 models qualify · AHRI 215725526	82.7(50 is the typical model of its size class)Z4SOV-48HDMB-USHH19 of 26 models qualify · AHRI 217752809
Ducted, 5 tons and up	58.3(50 is the typical model of its size class)PXV60H2A1 of 4 models qualify · AHRI 217753792	None on this board (0 of 2 models qualify)
Non-ducted, up to 1.5 tons	96.7(50 is the typical model of its size class) (higher)MOS06H2BH0Awith ductless indoor unit MHW06H2BHRB38 of 48 models qualify · AHRI 215725442	85.9(50 is the typical model of its size class)ZMSB-09HV-USHHR2-Owith ductless indoor unit ZMSB-09HV-USHHR2-I31 of 39 models qualify · AHRI 216097679
Non-ducted, 2 tons	89.4(50 is the typical model of its size class) (higher)MOS24H2BH0Awith ductless indoor unit MCS24H2BHRA9 of 9 models qualify · AHRI 217230001	77.2(50 is the typical model of its size class)ZMSB-24HV-USHHCR2-Owith ductless indoor unit ZMSB-24HV-USHHCR2-I7 of 9 models qualify · AHRI 216097676
Non-ducted, 2.5–3 tons	89.4(50 is the typical model of its size class) (higher)MOS36H2BH0Awith ductless indoor unit MFC36H2BHRA16 of 20 models qualify · AHRI 217230015	72.6(50 is the typical model of its size class)Z4SOV-36HDMB-USHH9 of 13 models qualify · AHRI 217752807
Non-ducted, 3.5–4.5 tons	73.4(50 is the typical model of its size class) (higher)MOM48H2BH6AAlso listed as MOM48H2BH6B11 of 12 models qualify · AHRI 215725527	69.9(50 is the typical model of its size class)Z4SOV-53HDMB-USHH6 of 6 models qualify · AHRI 217752813
Non-ducted, 5 tons and up	None on this board (0 of 2 models qualify)	None on this board (0 of 2 models qualify)

All-around best

Best all-around model per size and duct type. Score = 50% heating, the mean of its peer percentiles on COP at 5°F, Capacity retention at 5°F, HSPF2, plus 50% cooling, the mean of its peer percentiles on SEER2 and EER2 (share of the other models in its peer group it beats, 0–100). All five ratings are required; there is no minimum heat kept at 5°F. In each duct type a model is sold in, it is scored on its pairing of that type with the best score; equal scores (one decimal) go to the higher cold-climate score, then the higher heating capacity at 5°F.
Size and duct type	InnovairAll-around score, best model	ZEROAll-around score, best model
Ducted, up to 1.5 tons	86.7(50 is the typical model of its size class) (higher)MOS09H2BH0Awith ducted air handler MDL09H2MHWA17 of 18 models have all five ratings · AHRI 215725467	77.4(50 is the typical model of its size class)Z4SOV-18HDMB-USHH6 of 7 models have all five ratings · AHRI 217752800
Ducted, 2 tons	79.6(50 is the typical model of its size class)GOV36H2BAwith ducted air handler GAV24B2A10 of 11 models have all five ratings · AHRI 215318726	79.6(50 is the typical model of its size class)ZOV-24HDGBwith ducted air handler ZAV-24HDGB12 of 13 models have all five ratings · AHRI 217619841
Ducted, 2.5–3 tons	83.6(50 is the typical model of its size class)MOM36H2BH5AAlso listed as MOM36H2BH5B25 of 27 models have all five ratings · AHRI 215725523	83.6(50 is the typical model of its size class)Z4SOV-36HDMB-USHH18 of 20 models have all five ratings · AHRI 217752806
Ducted, 3.5–4.5 tons	85.1(50 is the typical model of its size class)MOM48H2BM6AAlso listed as MOM48H2BM6B20 of 23 models have all five ratings · AHRI 215725499	85.1(50 is the typical model of its size class)Z4SOV-48HDMB-USAlso listed as Z6SOV-48HDMB-US23 of 26 models have all five ratings · AHRI 217138410
Ducted, 5 tons and up	67.5(50 is the typical model of its size class) (higher)MOS60H2BM0Awith ducted air handler MDH60H2MHWA4 of 4 models have all five ratings · AHRI 215725466	64.7(50 is the typical model of its size class)Z4SOV-60HDMB-US2 of 2 models have all five ratings · AHRI 217138413
Non-ducted, up to 1.5 tons	96.2(50 is the typical model of its size class) (higher)MOS06H2BH0Awith ductless indoor unit MHW06H2BHRB48 of 48 models have all five ratings · AHRI 215725442	86.7(50 is the typical model of its size class)ZMSB-09HV-USHHR2-Owith ductless indoor unit ZMSB-09HV-USHHR2-I39 of 39 models have all five ratings · AHRI 216097679
Non-ducted, 2 tons	86.8(50 is the typical model of its size class) (higher)MOS24H2BM0Awith ductless indoor unit MHW24H2BHRB9 of 9 models have all five ratings · AHRI 215725441	74.3(50 is the typical model of its size class)ZMSB-24HV-USHHR2-Owith ductless indoor unit ZMSB-24HV-USHHR2-I9 of 9 models have all five ratings · AHRI 216097682
Non-ducted, 2.5–3 tons	78.3(50 is the typical model of its size class) (higher)MOM36H2BH5AAlso listed as MOM36H2BH5B20 of 20 models have all five ratings · AHRI 215725522	66.3(50 is the typical model of its size class)Z4SOV-36HDMB-USHH13 of 13 models have all five ratings · AHRI 217752805
Non-ducted, 3.5–4.5 tons	75.6(50 is the typical model of its size class) (higher)MOM48H2BH6AAlso listed as MOM48H2BH6B12 of 12 models have all five ratings · AHRI 215725525	62.6(50 is the typical model of its size class)Z4SOV-53HDMB-USHH6 of 6 models have all five ratings · AHRI 217752811
Non-ducted, 5 tons and up	58.6(50 is the typical model of its size class) (higher)MOM60H2BM6AAlso listed as MOM60H2BM6B2 of 2 models have all five ratings · AHRI 215835696	32.5(50 is the typical model of its size class)Z4SOV-60HDMB-USAlso listed as Z6SOV-60HDMB-US2 of 2 models have all five ratings · AHRI 217138412

All-around board, every manufacturer

Standout model on each rating

Each manufacturer’s model that beats the largest share of comparable models on the rating; the higher share is in bold.

Top model per rating by peer percentile, with its AHRI-certified value and peer group
Rating	Innovair	ZERO
COP at 5°F	beats 100% · 2.80MOM27H2XE3ANon-ducted, 2.5–3 tons	beats 99% · 2.80ZOU-42HDCA-S14Ducted, 3.5–4.5 tons
Capacity retention at 5°F	beats 100% · 133%QOS09H2BH0ADucted, up to 1.5 tons	beats 97% · 103%ZRRV07HPBYFC-18SAlso listed as ZPRVO7HPBYFC-18S, ZPRV07HPBYFC-18SDucted, 2 tons
HSPF2	beats 99% · 14.8MOS06H2BH0ANon-ducted, up to 1.5 tons	beats 99% · 11.0Z4SOV-48HDMB-USHHDucted, 3.5–4.5 tons
SEER2	beats 99% · 22.0POM27H2BM3ADucted, 2.5–3 tons	beats 99% · 22.0Z3SOV-27HDTB-USDucted, 2.5–3 tons
EER2	beats 99% · 18.0MOS06H2BH0ANon-ducted, up to 1.5 tons	beats 93% · 13.3ZOV-24HDGBDucted, 2 tons
Heating capacity at 5°F	beats 98% · 19,600 Btu/hSHV18H2BADucted, up to 1.5 tons	beats 97% · 39,000 Btu/hZSOVA-36HDMB-USHHDucted, 2.5–3 tons

More comparisons

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Innovair vs ZERO heat pumps