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Acekool vs WINDAIR heat pumps

Measured against models of the same size and duct type, WINDAIR scores higher on 4 of the 6 ratings. Acekool has 13 outdoor models, WINDAIR has 13 outdoor models. Acekool and WINDAIR have no QMID on file and are not ranked.

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CompareData as of updated · 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.
Acekool and WINDAIR 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, WINDAIR scores higher on 4 of the 6 ratings.
  • Acekool
  • WINDAIR
  • Other ranked manufacturers
AcekoolWINDAIR

Source: AHRI Directory, NEEP · as of

Average peer percentile, raw median and rank among ranked manufacturers
RatingAcekoolWINDAIR
Efficiency index36%median —65%median —
COP at 5°F21%median 1.8036%median 1.80
Capacity retention at 5°F39%median 70%44%median 70%
HSPF232% (higher)median 8.527% (higher)median 8.5
SEER246% (higher)median 19.037% (higher)median 18.5
EER238%median 10.050%median 11.1
Heating capacity at 5°F35%median 8,700 Btu/h40%median 8,400 Btu/h
Outdoor models1313
AHRI certifications1313

Share of models meeting each standard

Percent of each manufacturer’s models with a qualifying certification
StandardAcekoolWINDAIR
CEE 2025 Tier 1 (Split ASHP)84.6%11 models23.1%3 models
CEE 2026 Tier 1 (Split ASHP)76.9%10 models23.1%3 models
CEE Advanced Tier (Split ASHP)0%0 models0%0 models
Xcel Energy Colorado cold-climate ASHP (2025)61.5%8 models15.4%2 models
DOE Cold Climate Heat Pump Challenge0%0 models0%0 models
ENERGY STAR Cold Climate30.8%4 models0%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
  • Acekool
  • WINDAIR
  • All models of the group
Non-ducted, up to 1.5 tons1.902,417 modelsNon-ducted, 2 tons1.87611 modelsNon-ducted, 2.5–3 tons1.85975 modelsmedian

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

Source: AHRI Directory · as of

Models per peer group · efficiency index within the group
Size and duct typeAcekoolWINDAIR
Non-ducted, up to 1.5 tons10 · index 37%10 · index 65%
Non-ducted, 2 tons2 · index 35%2 · index —
Non-ducted, 2.5–3 tons1 · index 23%1 · index —

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 typeAcekoolCold-climate score, best modelWINDAIRCold-climate score, best model
Non-ducted, up to 1.5 tons47.5(50 is the typical model of its size class)CMS12-2 PROwith ductless indoor unit CMS12-2 PRO8 of 10 models qualify · AHRI 21698096375.0(50 is the typical model of its size class) (higher)DWH09UW3SXETE00/Owith ductless indoor unit DWH09UW3SXETE00/I2 of 10 models qualify · AHRI 202021941
Non-ducted, 2 tonsNone on this board (0 of 2 models qualify)None on this board (0 of 2 models qualify)
Non-ducted, 2.5–3 tonsNone on this board (0 of 1 models qualify)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 typeAcekoolAll-around score, best modelWINDAIRAll-around score, best model
Non-ducted, up to 1.5 tons60.6(50 is the typical model of its size class)CMS9-2 PROwith ductless indoor unit CMS9-2 PRO10 of 10 models have all five ratings · AHRI 21698096285.1(50 is the typical model of its size class) (higher)DWH09UW3SXETE00/Owith ductless indoor unit DWH09UW3SXETE00/I3 of 10 models have all five ratings · AHRI 202021941
Non-ducted, 2 tons46.0(50 is the typical model of its size class)CMS24 PROwith ductless indoor unit CMS24 PRO2 of 2 models have all five ratings · AHRI 213857786None on this board (0 of 2 models have all five ratings)
Non-ducted, 2.5–3 tons23.4(50 is the typical model of its size class)CMS36with ductless indoor unit CMS361 of 1 models have all five ratings · AHRI 213804783None on this board (0 of 1 models have all five ratings)

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
RatingAcekoolWINDAIR
COP at 5°Fbeats 26% · 1.80CMS24Non-ducted, 2 tonsbeats 78% · 2.10DWH09UW3SXETE00/ONon-ducted, up to 1.5 tons
Capacity retention at 5°Fbeats 64% · 77%CMS9-2 PRONon-ducted, up to 1.5 tonsbeats 65% · 78%DWH09UW3SXETE00/ONon-ducted, up to 1.5 tons
HSPF2beats 57% · 9.5CMS12-2 PRONon-ducted, up to 1.5 tonsbeats 79% · 10.5DWH09UW3SXETE00/ONon-ducted, up to 1.5 tons
SEER2beats 79% · 23.5CMS9-2 PRONon-ducted, up to 1.5 tonsbeats 96% · 27.5DWH09UW3SXETE00/ONon-ducted, up to 1.5 tons
EER2beats 68% · 13.0CMS12 PRONon-ducted, up to 1.5 tonsbeats 93% · 15.5DWH09UW3SXETE00/ONon-ducted, up to 1.5 tons
Heating capacity at 5°Fbeats 66% · 11,900 Btu/hCMS12 PRONon-ducted, up to 1.5 tonsbeats 66% · 11,900 Btu/hDWH18UR3SBBTE/ONon-ducted, up to 1.5 tons

More comparisons

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