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MULTIZONE vs SEA BREEZE heat pumps

Measured against models of the same size and duct type, MULTIZONE and SEA BREEZE split the 6 ratings 3–3. MULTIZONE has 9 outdoor models, SEA BREEZE has 9 outdoor models. MULTIZONE and SEA BREEZE 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.
MULTIZONE and SEA BREEZE 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, MULTIZONE and SEA BREEZE split the 6 ratings 3–3.
  • MULTIZONE
  • SEA BREEZE
  • Other ranked manufacturers
MULTIZONESEA BREE…

Source: AHRI Directory, NEEP · as of

Average peer percentile, raw median and rank among ranked manufacturers
RatingMULTIZONESEA BREEZE
Efficiency index47% (higher)median —40% (higher)median —
COP at 5°F14%median 1.7854%median 1.93
Capacity retention at 5°F33% (higher)median 68%25% (higher)median 62%
HSPF223%median 8.532%median 8.7
SEER231%median 18.540%median 20.8
EER247% (higher)median 10.937% (higher)median 10.8
Heating capacity at 5°F51% (higher)median 10,150 Btu/h24% (higher)median 9,850 Btu/h
Outdoor models99
AHRI certifications99

Share of models meeting each standard

Percent of each manufacturer’s models with a qualifying certification
StandardMULTIZONESEA BREEZE
CEE 2025 Tier 1 (Split ASHP)22.2%2 models55.6%5 models
CEE 2026 Tier 1 (Split ASHP)22.2%2 models55.6%5 models
CEE Advanced Tier (Split ASHP)0%0 models0%0 models
Xcel Energy Colorado cold-climate ASHP (2025)11.1%1 models22.2%2 models
DOE Cold Climate Heat Pump Challenge0%0 models0%0 models
ENERGY STAR Cold Climate0%0 models22.2%2 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
  • MULTIZONE
  • SEA BREEZE
  • 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 typeMULTIZONESEA BREEZE
Non-ducted, up to 1.5 tons6 · index 47%5 · index 41%
Non-ducted, 2 tons2 · index —1 · index 27%
Non-ducted, 2.5–3 tons1 · index —3 · index 44%

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 typeMULTIZONECold-climate score, best modelSEA BREEZECold-climate score, best model
Non-ducted, up to 1.5 tons34.7(50 is the typical model of its size class)MIT12H2G31(O)with ductless indoor unit MIT12H2G31(I)1 of 6 models qualify · AHRI 985021856.7(50 is the typical model of its size class) (higher)9H421YOMIwith ductless indoor unit 9H421YIMI2 of 5 models qualify · AHRI 208650692
Non-ducted, 2 tonsNone on this board (0 of 2 models qualify)None on this board (0 of 1 models qualify)
Non-ducted, 2.5–3 tonsNone on this board (0 of 1 models qualify)None on this board (0 of 3 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 typeMULTIZONEAll-around score, best modelSEA BREEZEAll-around score, best model
Non-ducted, up to 1.5 tons46.8(50 is the typical model of its size class)MIT18H2G31(O)with ductless indoor unit MIT18H2G31(I)2 of 6 models have all five ratings · AHRI 985021955.7(50 is the typical model of its size class) (higher)9H421ZOMIwith ductless indoor unit 9H421ZIMI5 of 5 models have all five ratings · AHRI 208650694
Non-ducted, 2 tonsNone on this board (0 of 2 models have all five ratings)27.2(50 is the typical model of its size class)24H421ZOMIwith ductless indoor unit 24H421ZIMI1 of 1 models have all five ratings · AHRI 208650697
Non-ducted, 2.5–3 tonsNone on this board (0 of 1 models have all five ratings)53.1(50 is the typical model of its size class)30H421ZOMIwith ductless indoor unit 30H421ZIMI2 of 3 models have all five ratings · AHRI 208650698

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
RatingMULTIZONESEA BREEZE
COP at 5°Fbeats 22% · 1.80MIT18H2G31(O)Non-ducted, up to 1.5 tonsbeats 87% · 2.0136H421ZOMINon-ducted, 2.5–3 tons
Capacity retention at 5°Fbeats 39% · 70%MIT12H2G31(O)Non-ducted, up to 1.5 tonsbeats 39% · 70%9H421YOMINon-ducted, up to 1.5 tons
HSPF2beats 57% · 9.5MIT12H2G31(O)Non-ducted, up to 1.5 tonsbeats 53% · 9.49H421ZOMINon-ducted, up to 1.5 tons
SEER2beats 67% · 22.5MIT18H2G31(O)Non-ducted, up to 1.5 tonsbeats 65% · 21.030H421ZOMINon-ducted, 2.5–3 tons
EER2beats 80% · 13.7MIT09H2G31(O)Non-ducted, up to 1.5 tonsbeats 75% · 12.230H421ZOMINon-ducted, 2.5–3 tons
Heating capacity at 5°Fbeats 66% · 11,900 Btu/hMIT18H2G31(O)Non-ducted, up to 1.5 tonsbeats 63% · 11,700 Btu/h18H421ZOMINon-ducted, up to 1.5 tons

More comparisons

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