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.

Gridless and SMARTFLEX 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, Gridless scores higher on 6 of the 6 ratings.

Gridless
SMARTFLEX
Other ranked manufacturers

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

Average peer percentile, raw median and rank among ranked manufacturers
Rating	Gridless	SMARTFLEX
Efficiency index	60% (higher)median —	29% (higher)median —
COP at 5°F	40% (higher)median 1.84	19% (higher)median 1.80
Capacity retention at 5°F	77% (higher)median 86%	65% (higher)median 74%
HSPF2	60% (higher)median 9.5	28% (higher)median 8.5
SEER2	68% (higher)median 21.0	21% (higher)median 17.5
EER2	56% (higher)median 12.5	19% (higher)median 10.2
Heating capacity at 5°F	67% (higher)median 22,800 Btu/h	59% (higher)median 21,800 Btu/h
Outdoor models	11	11
AHRI certifications	11	18

Share of models meeting each standard

Percent of each manufacturer’s models with a qualifying certification
Standard	Gridless	SMARTFLEX
CEE 2025 Tier 1 (Split ASHP)	100%11 models	36.4%4 models
CEE 2026 Tier 1 (Split ASHP)	100%11 models	36.4%4 models
CEE Advanced Tier (Split ASHP)	0%0 models	0%0 models
Xcel Energy Colorado cold-climate ASHP (2025)	100%11 models	63.6%7 models
DOE Cold Climate Heat Pump Challenge	0%0 models	0%0 models
ENERGY STAR Cold Climate	90.9%10 models	0%0 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 · 7 groups where both have models

Gridless
SMARTFLEX
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	Gridless	SMARTFLEX
Ducted, 2 tons	1 · index 46%	1 · index 28%
Ducted, 2.5–3 tons	1 · index 63%	1 · index 24%
Ducted, 3.5–4.5 tons	1 · index 57%	1 · index 28%
Ducted, up to 1.5 tons	None	1 · index 22%
Non-ducted, up to 1.5 tons	4 · index 63%	6 · index 22%
Non-ducted, 2 tons	2 · index 64%	1 · index 55%
Non-ducted, 2.5–3 tons	1 · index 70%	3 · index 41%
Non-ducted, 3.5–4.5 tons	1 · index 45%	1 · index 19%

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	GridlessCold-climate score, best model	SMARTFLEXCold-climate score, best model
Ducted, up to 1.5 tons	No models in this size class	35.2(50 is the typical model of its size class)DHS18CMB22S1 of 1 models qualify · AHRI 207616613
Ducted, 2 tons	57.5(50 is the typical model of its size class) (higher)O-AYC24SD-1with ducted air handler I-AYC24VAH-11 of 1 models qualify · AHRI 213249673	45.7(50 is the typical model of its size class)DHS24CMB22S1 of 1 models qualify · AHRI 207616615
Ducted, 2.5–3 tons	75.1(50 is the typical model of its size class) (higher)O-AYC36SD-1with ducted air handler I-AYC36VAH-11 of 1 models qualify · AHRI 213249674	37.8(50 is the typical model of its size class)DHS36CMB22S1 of 1 models qualify · AHRI 207616618
Ducted, 3.5–4.5 tons	56.6(50 is the typical model of its size class) (higher)O-AYC48SD-1with ducted air handler I-AYC48VAH-11 of 1 models qualify · AHRI 213249675	40.5(50 is the typical model of its size class)DHS42CMB22S1 of 1 models qualify · AHRI 207616621
Non-ducted, up to 1.5 tons	72.9(50 is the typical model of its size class) (higher)O-AYD09SD-1with ductless indoor unit I-AYD09W-14 of 4 models qualify · AHRI 213265552	64.2(50 is the typical model of its size class)DHS18CMB22S5 of 6 models qualify · AHRI 207616612
Non-ducted, 2 tons	56.8(50 is the typical model of its size class)O-AYD24SD-32 of 2 models qualify · AHRI 213255584	66.1(50 is the typical model of its size class) (higher)DHS24CMB22S1 of 1 models qualify · AHRI 207616614
Non-ducted, 2.5–3 tons	64.0(50 is the typical model of its size class) (higher)O-AYD36SD-41 of 1 models qualify · AHRI 213255585	44.1(50 is the typical model of its size class)DHP36CSB22Swith ductless indoor unit DHP36NWB22S3 of 3 models qualify · AHRI 209818487
Non-ducted, 3.5–4.5 tons	41.8(50 is the typical model of its size class) (higher)O-AYD42SD-51 of 1 models qualify · AHRI 213255586	31.6(50 is the typical model of its size class)DHS42CMB22S1 of 1 models qualify · AHRI 207616620

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	GridlessAll-around score, best model	SMARTFLEXAll-around score, best model
Ducted, up to 1.5 tons	No models in this size class	22.0(50 is the typical model of its size class)DHS18CMB22S1 of 1 models have all five ratings · AHRI 207616613
Ducted, 2 tons	46.3(50 is the typical model of its size class) (higher)O-AYC24SD-1with ducted air handler I-AYC24VAH-11 of 1 models have all five ratings · AHRI 213249673	27.7(50 is the typical model of its size class)DHS24CMB22S1 of 1 models have all five ratings · AHRI 207616615
Ducted, 2.5–3 tons	63.2(50 is the typical model of its size class) (higher)O-AYC36SD-1with ducted air handler I-AYC36VAH-11 of 1 models have all five ratings · AHRI 213249674	24.1(50 is the typical model of its size class)DHS36CMB22S1 of 1 models have all five ratings · AHRI 207616618
Ducted, 3.5–4.5 tons	57.3(50 is the typical model of its size class) (higher)O-AYC48SD-1with ducted air handler I-AYC48VAH-11 of 1 models have all five ratings · AHRI 213249675	28.0(50 is the typical model of its size class)DHS42CMB22S1 of 1 models have all five ratings · AHRI 207616621
Non-ducted, up to 1.5 tons	81.4(50 is the typical model of its size class) (higher)O-AYD09SD-1with ductless indoor unit I-AYD09W-14 of 4 models have all five ratings · AHRI 213265552	50.6(50 is the typical model of its size class)DHS18CMB22S6 of 6 models have all five ratings · AHRI 207616612
Non-ducted, 2 tons	67.5(50 is the typical model of its size class) (higher)O-AYD24SD-32 of 2 models have all five ratings · AHRI 213255584	55.4(50 is the typical model of its size class)DHS24CMB22S1 of 1 models have all five ratings · AHRI 207616614
Non-ducted, 2.5–3 tons	69.5(50 is the typical model of its size class) (higher)O-AYD36SD-41 of 1 models have all five ratings · AHRI 213255585	47.8(50 is the typical model of its size class)DHP36CSB22Swith ductless indoor unit DHP36NWB22S3 of 3 models have all five ratings · AHRI 209818487
Non-ducted, 3.5–4.5 tons	44.5(50 is the typical model of its size class) (higher)O-AYD42SD-51 of 1 models have all five ratings · AHRI 213255586	18.7(50 is the typical model of its size class)DHS42CMB22S1 of 1 models have all five ratings · AHRI 207616620

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	Gridless	SMARTFLEX
COP at 5°F	beats 75% · 2.05O-AYC36SD-1Ducted, 2.5–3 tons	beats 53% · 1.85DHP36CSB22SNon-ducted, 2.5–3 tons
Capacity retention at 5°F	beats 99% · 113%O-AYD36SD-4Non-ducted, 2.5–3 tons	beats 98% · 115%DHS24CMB22SNon-ducted, 2 tons
HSPF2	beats 83% · 9.5O-AYC36SD-1Ducted, 2.5–3 tons	beats 73% · 10.0DHS24CMB22SNon-ducted, 2 tons
SEER2	beats 89% · 25.5O-AYD09SD-1Non-ducted, up to 1.5 tons	beats 51% · 20.0DHP30CSB22SNon-ducted, 2.5–3 tons
EER2	beats 89% · 14.5O-AYD09SD-1Non-ducted, up to 1.5 tons	beats 53% · 11.3DHP30CSB22SNon-ducted, 2.5–3 tons
Heating capacity at 5°F	beats 92% · 18,000 Btu/hO-AYD18SD-2Non-ducted, up to 1.5 tons	beats 99% · 21,800 Btu/hDHS18CMB22SNon-ducted, up to 1.5 tons

More comparisons

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Gridless vs SMARTFLEX heat pumps