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.

Kerr and Wells 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, Kerr scores higher on 5 of the 6 ratings.

Kerr
Wells
Other ranked manufacturers

Source: AHRI Directory, NEEP · as of Oct 11, 2026

Average peer percentile, raw median and rank among ranked manufacturers
Rating	Kerr	Wells
Efficiency index	66% (higher)median —	63% (higher)median —
COP at 5°F	59%median 2.00	64%median 2.10
Capacity retention at 5°F	77% (higher)median 95%	61% (higher)median 75%
HSPF2	78% (higher)median 10.0	74% (higher)median 10.0
SEER2	64% (higher)median 19.5	62% (higher)median 19.4
EER2	62% (higher)median 11.9	59% (higher)median 12.0
Heating capacity at 5°F	73% (higher)median 18,500 Btu/h	62% (higher)median 19,000 Btu/h
Outdoor models	38	37
AHRI certifications	113	121

Share of models meeting each standard

Percent of each manufacturer’s models with a qualifying certification
Standard	Kerr	Wells
CEE 2025 Tier 1 (Split ASHP)	78.9%30 models	86.5%32 models
CEE 2026 Tier 1 (Split ASHP)	76.3%29 models	83.8%31 models
CEE Advanced Tier (Split ASHP)	2.6%1 models	2.7%1 models
Xcel Energy Colorado cold-climate ASHP (2025)	89.5%34 models	81.1%30 models
DOE Cold Climate Heat Pump Challenge	2.6%1 models	2.7%1 models
ENERGY STAR Cold Climate	89.5%34 models	83.8%31 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 · 8 groups where both have models

Kerr
Wells
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 11, 2026

Models per peer group · efficiency index within the group
Size and duct type	Kerr	Wells
Ducted, up to 1.5 tons	7 · index 75%	9 · index 80%
Ducted, 2 tons	3 · index 60%	5 · index 73%
Ducted, 2.5–3 tons	7 · index 66%	7 · index 67%
Ducted, 3.5–4.5 tons	5 · index 61%	7 · index 63%
Ducted, 5 tons and up	None	1 · index 63%
Non-ducted, up to 1.5 tons	18 · index 66%	16 · index 58%
Non-ducted, 2 tons	3 · index 58%	4 · index 53%
Non-ducted, 2.5–3 tons	3 · index 67%	4 · index 54%
Non-ducted, 3.5–4.5 tons	2 · index 67%	3 · index 57%
Non-ducted, 5 tons and up	None	1 · 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	KerrCold-climate score, best model	WellsCold-climate score, best model
Ducted, up to 1.5 tons	82.3(50 is the typical model of its size class)A-KHP18SA-1with ducted air handler B-KHP18DA-17 of 7 models qualify · AHRI 217482433	93.5(50 is the typical model of its size class) (higher)WOS-06PRE/230with ducted air handler WIDL-06MOC/2309 of 9 models qualify · AHRI 215864077
Ducted, 2 tons	85.7(50 is the typical model of its size class)A-KHP24SA-1with ducted air handler B-KHP24DA-13 of 3 models qualify · AHRI 217482436	85.7(50 is the typical model of its size class)WOS-24PRE/230with ducted air handler WIDH-24MOC/2305 of 5 models qualify · AHRI 215864084
Ducted, 2.5–3 tons	82.5(50 is the typical model of its size class)A-KHP365A-17 of 7 models qualify · AHRI 216097146	82.5(50 is the typical model of its size class)WOM-36HH5/2307 of 7 models qualify · AHRI 215864112
Ducted, 3.5–4.5 tons	82.7(50 is the typical model of its size class)A-KHP486A-15 of 5 models qualify · AHRI 216097150	82.7(50 is the typical model of its size class)WOM-48HH6/2307 of 7 models qualify · AHRI 215864115
Ducted, 5 tons and up	No models in this size class	None on this board (0 of 1 models qualify)
Non-ducted, up to 1.5 tons	96.7(50 is the typical model of its size class) (higher)A-KHP06SA-1with ductless indoor unit B-KHP06SA-112 of 18 models qualify · AHRI 216097110	94.4(50 is the typical model of its size class)WOS-06PRE/230with ductless indoor unit WI1C-06MOC/23011 of 16 models qualify · AHRI 215864073
Non-ducted, 2 tons	89.4(50 is the typical model of its size class)A-KHP24SA-1with ductless indoor unit B-KHP24CA-13 of 3 models qualify · AHRI 217482434	89.4(50 is the typical model of its size class)WOS-24PRE/230with ductless indoor unit WI4C-24MOC/2304 of 4 models qualify · AHRI 215864072
Non-ducted, 2.5–3 tons	78.0(50 is the typical model of its size class) (higher)A-KHP365A-13 of 3 models qualify · AHRI 216097148	72.6(50 is the typical model of its size class)WOM-36HH5/2304 of 4 models qualify · AHRI 215864113
Non-ducted, 3.5–4.5 tons	73.4(50 is the typical model of its size class) (higher)A-KHP486A-12 of 2 models qualify · AHRI 216097152	69.9(50 is the typical model of its size class)WOM-60HH6/2303 of 3 models qualify · AHRI 215864119
Non-ducted, 5 tons and up	No models in this size class	None on this board (0 of 1 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	KerrAll-around score, best model	WellsAll-around score, best model
Ducted, up to 1.5 tons	86.5(50 is the typical model of its size class)A-KHP09SA-1with ducted air handler B-KHP09DA-17 of 7 models have all five ratings · AHRI 217482423	95.0(50 is the typical model of its size class) (higher)WOS-06PRE/230with ducted air handler WIDL-06MOC/2309 of 9 models have all five ratings · AHRI 215864077
Ducted, 2 tons	78.4(50 is the typical model of its size class)A-KHP24SA-1with ducted air handler B-KHP24DA-13 of 3 models have all five ratings · AHRI 217482436	79.6(50 is the typical model of its size class) (higher)WDHP-2436T-Gwith ducted air handler WDAH-24MOC-G5 of 5 models have all five ratings · AHRI 217048501
Ducted, 2.5–3 tons	83.6(50 is the typical model of its size class)A-KHP365A-17 of 7 models have all five ratings · AHRI 216097146	83.6(50 is the typical model of its size class)WOM-36HH5/2307 of 7 models have all five ratings · AHRI 215864112
Ducted, 3.5–4.5 tons	83.9(50 is the typical model of its size class)A-KHP486A-15 of 5 models have all five ratings · AHRI 216097150	85.1(50 is the typical model of its size class) (higher)WOM-48RH6/2307 of 7 models have all five ratings · AHRI 215864100
Ducted, 5 tons and up	No models in this size class	62.5(50 is the typical model of its size class)WOM-60RH6/2301 of 1 models have all five ratings · AHRI 215864103
Non-ducted, up to 1.5 tons	96.2(50 is the typical model of its size class) (higher)A-KHP06SA-1with ductless indoor unit B-KHP06SA-116 of 18 models have all five ratings · AHRI 216097110	93.8(50 is the typical model of its size class)WOS-06PRE/230with ductless indoor unit WIHW-06MOC/23016 of 16 models have all five ratings · AHRI 215864044
Non-ducted, 2 tons	76.4(50 is the typical model of its size class) (higher)A-KHP24SA-1with ductless indoor unit B-KHP24SA-1Also listed as A-ZKP24SA-13 of 3 models have all five ratings · AHRI 216097114	74.3(50 is the typical model of its size class)WOS-24QUA/230with ductless indoor unit WIHW-24MOC/2304 of 4 models have all five ratings · AHRI 215864043
Non-ducted, 2.5–3 tons	78.3(50 is the typical model of its size class) (higher)A-KHP365A-13 of 3 models have all five ratings · AHRI 216097145	66.3(50 is the typical model of its size class)WOM-36HH5/2304 of 4 models have all five ratings · AHRI 215864111
Non-ducted, 3.5–4.5 tons	75.6(50 is the typical model of its size class) (higher)A-KHP486A-12 of 2 models have all five ratings · AHRI 216097149	62.6(50 is the typical model of its size class)WOM-60HH6/2303 of 3 models have all five ratings · AHRI 215864117
Non-ducted, 5 tons and up	No models in this size class	32.5(50 is the typical model of its size class)WOM-60RH6/2301 of 1 models have all five ratings · AHRI 215864102

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	Kerr	Wells
COP at 5°F	beats 97% · 2.40A-KHP06SA-1Non-ducted, up to 1.5 tons	beats 99% · 2.51WOS-12QUA/230Non-ducted, up to 1.5 tons
Capacity retention at 5°F	beats 100% · 150%A-KZP06SA-1Also listed as A-ZKP06SA-1Non-ducted, up to 1.5 tons	beats 98% · 126%WOS-09PRE/230Non-ducted, up to 1.5 tons
HSPF2	beats 100% · 15.6A-KZP06SA-1Also listed as A-ZKP06SA-1Non-ducted, up to 1.5 tons	beats 99% · 11.0WOM-48HH6/230Ducted, 3.5–4.5 tons
SEER2	beats 100% · 27.0A-ZKP15SA-1Ducted, up to 1.5 tons	beats 96% · 20.4WOM-48RH6/230Ducted, 3.5–4.5 tons
EER2	beats 99% · 18.0A-KHP06SA-1Non-ducted, up to 1.5 tons	beats 99% · 14.4WOS-06PRE/230Ducted, up to 1.5 tons
Heating capacity at 5°F	beats 99% · 22,600 Btu/hA-KZP18SA-1Also listed as A-ZKP18SA-1Non-ducted, up to 1.5 tons	beats 97% · 39,000 Btu/hWDHP-36HHDucted, 2.5–3 tons

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Kerr vs Wells heat pumps