Bestcold vs Impecca heat pumps

Measured against models of the same size and duct type, Impecca scores higher on 6 of the 6 ratings. Bestcold has 7 outdoor models, Impecca has 7 outdoor models. Bestcold and Impecca have no QMID on file and are not ranked.

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CompareData as of Oct 11, 2026updated Oct 11, 2026 · sources

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.

Bestcold and Impecca 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, Impecca scores higher on 6 of the 6 ratings.

Bestcold
Impecca
Other ranked manufacturers

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

Average peer percentile, raw median and rank among ranked manufacturers
Rating	Bestcold	Impecca
Efficiency index	22%median —	56%median —
COP at 5°F	19%median 1.80	44%median 1.85
Capacity retention at 5°F	30%median 70%	66%median 76%
HSPF2	19%median 8.5	55%median 10.0
SEER2	27%median 19.0	61%median 21.0
EER2	16%median 10.0	53%median 12.0
Heating capacity at 5°F	32%median 8,600 Btu/h	70%median 21,600 Btu/h
Outdoor models	7	7
AHRI certifications	7	15

Share of models meeting each standard

Percent of each manufacturer’s models with a qualifying certification
Standard	Bestcold	Impecca
CEE 2025 Tier 1 (Split ASHP)	71.4%5 models	100%7 models
CEE 2026 Tier 1 (Split ASHP)	57.1%4 models	100%7 models
CEE Advanced Tier (Split ASHP)	0%0 models	0%0 models
Xcel Energy Colorado cold-climate ASHP (2025)	57.1%4 models	100%7 models
DOE Cold Climate Heat Pump Challenge	0%0 models	0%0 models
ENERGY STAR Cold Climate	0%0 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 · 3 groups where both have models

Bestcold
Impecca
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	Bestcold	Impecca
Ducted, up to 1.5 tons	None	1 · index 32%
Ducted, 2 tons	None	1 · index 46%
Ducted, 2.5–3 tons	None	2 · index 52%
Non-ducted, up to 1.5 tons	5 · index 21%	2 · index 58%
Non-ducted, 2 tons	1 · index 25%	2 · index 69%
Non-ducted, 2.5–3 tons	1 · index 23%	3 · index 61%

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	BestcoldCold-climate score, best model	ImpeccaCold-climate score, best model
Ducted, up to 1.5 tons	No models in this size class	36.0(50 is the typical model of its size class)ISAM-18221 of 1 models qualify · AHRI 215412927
Ducted, 2 tons	No models in this size class	50.1(50 is the typical model of its size class)ISAM-24221 of 1 models qualify · AHRI 215412928
Ducted, 2.5–3 tons	No models in this size class	52.1(50 is the typical model of its size class)ISAM-42222 of 2 models qualify · AHRI 215412930
Non-ducted, up to 1.5 tons	28.4(50 is the typical model of its size class)MYTW-12HPAC1/Owith ductless indoor unit MYTW-12HPAC1/IAlso listed as MYTW-12HPAC2/O4 of 5 models qualify · AHRI 214844424	73.6(50 is the typical model of its size class) (higher)ISAM-18222 of 2 models qualify · AHRI 215412925
Non-ducted, 2 tons	None on this board (0 of 1 models qualify)	76.1(50 is the typical model of its size class)ISAM-24222 of 2 models qualify · AHRI 215412926
Non-ducted, 2.5–3 tons	None on this board (0 of 1 models qualify)	73.7(50 is the typical model of its size class)ISAM-42223 of 3 models qualify · AHRI 215412924

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	BestcoldAll-around score, best model	ImpeccaAll-around score, best model
Ducted, up to 1.5 tons	No models in this size class	31.5(50 is the typical model of its size class)ISAM-18221 of 1 models have all five ratings · AHRI 215412927
Ducted, 2 tons	No models in this size class	45.9(50 is the typical model of its size class)ISAM-24221 of 1 models have all five ratings · AHRI 215412928
Ducted, 2.5–3 tons	No models in this size class	51.8(50 is the typical model of its size class)ISAM-42222 of 2 models have all five ratings · AHRI 215412930
Non-ducted, up to 1.5 tons	23.6(50 is the typical model of its size class)MYTW-12HPAC1/Owith ductless indoor unit MYTW-12HPAC1/IAlso listed as MYTW-12HPAC2/O5 of 5 models have all five ratings · AHRI 214844424	58.2(50 is the typical model of its size class) (higher)ISAM-18222 of 2 models have all five ratings · AHRI 215412925
Non-ducted, 2 tons	24.8(50 is the typical model of its size class)MYTW-24HPAC2/Owith ductless indoor unit MYTW-24HPAC2/I1 of 1 models have all five ratings · AHRI 214844428	71.5(50 is the typical model of its size class) (higher)ISAM-24222 of 2 models have all five ratings · AHRI 215412926
Non-ducted, 2.5–3 tons	23.4(50 is the typical model of its size class)MYTW-36HPAC2/Owith ductless indoor unit MYTW-36HPAC2/I1 of 1 models have all five ratings · AHRI 214844429	70.2(50 is the typical model of its size class) (higher)ISAM-42223 of 3 models have all five ratings · AHRI 215412924

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	Bestcold	Impecca
COP at 5°F	beats 26% · 1.80MYTW-24HPAC2/ONon-ducted, 2 tons	beats 90% · 2.22ISAM-1822Non-ducted, up to 1.5 tons
Capacity retention at 5°F	beats 46% · 70%MYTW-12HPAC1/OAlso listed as MYTW-12HPAC2/ONon-ducted, up to 1.5 tons	beats 78% · 90%ISAM-3622Non-ducted, 2.5–3 tons
HSPF2	beats 25% · 8.5MYTW-36HPAC2/ONon-ducted, 2.5–3 tons	beats 82% · 10.0ISAM-3622Non-ducted, 2.5–3 tons
SEER2	beats 35% · 19.0MYTW-36HPAC2/ONon-ducted, 2.5–3 tons	beats 98% · 24.5ISAS-2422Non-ducted, 2 tons
EER2	beats 25% · 10.0MYTW-24HPAC2/ONon-ducted, 2 tons	beats 90% · 13.1ISAS-2422Non-ducted, 2 tons
Heating capacity at 5°F	beats 61% · 11,600 Btu/hMYTW-18HPAC2/ONon-ducted, up to 1.5 tons	beats 84% · 13,800 Btu/hISAM-1822Non-ducted, up to 1.5 tons

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