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1HVAC vs THERMAL ZONE heat pumps

Measured against models of the same size and duct type, 1HVAC scores higher on 6 of the 6 ratings. 1HVAC has 70 outdoor models, THERMAL ZONE has 101 outdoor models. 1HVAC and THERMAL ZONE 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.
1HVAC and THERMAL ZONE 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, 1HVAC scores higher on 6 of the 6 ratings.
  • 1HVAC
  • THERMAL ZONE
  • Other ranked manufacturers
1HVACTHERMAL …

Source: AHRI Directory, NEEP · as of

Average peer percentile, raw median and rank among ranked manufacturers
Rating1HVACTHERMAL ZONE
Efficiency index61% (higher)median —30% (higher)median —
COP at 5°F57% (higher)median 2.0040% (higher)median 1.86
Capacity retention at 5°F59% (higher)median 78%26% (higher)median 46%
HSPF271% (higher)median 10.023% (higher)median 7.2
SEER264% (higher)median 19.824% (higher)median 14.3
EER255% (higher)median 12.031% (higher)median 10.6
Heating capacity at 5°F62% (higher)median 21,000 Btu/h29% (higher)median 18,550 Btu/h
Outdoor models70101
AHRI certifications1661,006

Share of models meeting each standard

Percent of each manufacturer’s models with a qualifying certification
Standard1HVACTHERMAL ZONE
CEE 2025 Tier 1 (Split ASHP)87.1%61 models7.9%8 models
CEE 2026 Tier 1 (Split ASHP)85.7%60 models5.9%6 models
CEE Advanced Tier (Split ASHP)4.3%3 models0%0 models
Xcel Energy Colorado cold-climate ASHP (2025)74.3%52 models7.9%8 models
DOE Cold Climate Heat Pump Challenge4.3%3 models0%0 models
ENERGY STAR Cold Climate77.1%54 models7.9%8 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 · 5 groups where both have models
  • 1HVAC
  • THERMAL ZONE
  • All models of the group
Ducted, up to 1.5 tons1.901,783 modelsDucted, 2 tons2.001,090 modelsDucted, 2.5–3 tons2.001,909 modelsDucted, 3.5–4.5 tons2.002,224 modelsDucted, 5 tons and up2.00321 modelsNon-ducted, up to 1.5 tons1.953,455 modelsNon-ducted, 2 tons2.00863 modelsNon-ducted, 2.5–3 tons2.001,106 modelsNon-ducted, 3.5–4.5 tons2.00564 modelsNon-ducted, 5 tons and up2.0585 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 type1HVACTHERMAL ZONE
Ducted, up to 1.5 tons8 · index 75%5 · index 34%
Ducted, 2 tons8 · index 65%11 · index 33%
Ducted, 2.5–3 tons12 · index 65%30 · index 26%
Ducted, 3.5–4.5 tons17 · index 65%38 · index 31%
Ducted, 5 tons and up1 · index 63%17 · index 28%
Non-ducted, up to 1.5 tons22 · index 59%None
Non-ducted, 2 tons6 · index 53%None
Non-ducted, 2.5–3 tons9 · index 48%None
Non-ducted, 3.5–4.5 tons6 · index 53%None
Non-ducted, 5 tons and up1 · index 59%None

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 type1HVACCold-climate score, best modelTHERMAL ZONECold-climate score, best model
Ducted, up to 1.5 tons86.7(50 is the typical model of its size class) (higher)ACIQ-18-HPDwith ducted air handler ACIQ-18W-WMB7 of 8 models qualify · AHRI 21698082172.0(50 is the typical model of its size class)TZP15AY18AJ2Nwith ducted air handler PE(S,T)23J1 of 5 models qualify · AHRI 217200657
Ducted, 2 tons85.7(50 is the typical model of its size class) (higher)ACIQ-24ZPL-HP230Cwith ducted air handler ACIQ-24CD-HH-MC8 of 8 models qualify · AHRI 21603228175.5(50 is the typical model of its size class)TZP15AY24AJ2Nwith ducted air handler L(E,F)W30BJ4 of 11 models qualify · AHRI 217200648
Ducted, 2.5–3 tons83.2(50 is the typical model of its size class) (higher)ACIQ-36ZPL-HP230Cwith ducted air handler ACIQ-36CD-HH-MC11 of 12 models qualify · AHRI 21603228272.6(50 is the typical model of its size class)TZP15AY36AJ2Nwith ducted air handler AEW37J+TDR2 of 30 models qualify · AHRI 217200653
Ducted, 3.5–4.5 tons85.1(50 is the typical model of its size class) (higher)ACIQ-60-HP32with ducted air handler ACIQ-60-AH3217 of 17 models qualify · AHRI 21538723765.9(50 is the typical model of its size class)TZID48H520ZCSwith indoor coil TZID60H520ZACD and furnace MGV96U120D5C3 of 38 models qualify · AHRI 218782171
Ducted, 5 tons and upNone on this board (0 of 1 models qualify)None on this board (0 of 17 models qualify)
Non-ducted, up to 1.5 tons96.7(50 is the typical model of its size class)ACIQ-06ZPL-HP230Cwith ductless indoor unit ACIQ-06W-HH-MD14 of 22 models qualify · AHRI 216032267No models in this size class
Non-ducted, 2 tons89.4(50 is the typical model of its size class)ACIQ-24ZPL-HP230Cwith ductless indoor unit ACIQ-24CC-HH-MC4 of 6 models qualify · AHRI 216032275No models in this size class
Non-ducted, 2.5–3 tons89.4(50 is the typical model of its size class)ACIQ-36ZPL-HP230Cwith ductless indoor unit ACIQ-36FM-HH-MD6 of 9 models qualify · AHRI 216032289No models in this size class
Non-ducted, 3.5–4.5 tons73.4(50 is the typical model of its size class)ACIQ-48Z-HH-M6C6 of 6 models qualify · AHRI 216032306No models in this size class
Non-ducted, 5 tons and upNone on this board (0 of 1 models qualify)No models in this size class

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 type1HVACAll-around score, best modelTHERMAL ZONEAll-around score, best model
Ducted, up to 1.5 tons86.5(50 is the typical model of its size class) (higher)ACIQ-09ZPL-HP230Cwith ducted air handler ACIQ-09CD-HH-MC8 of 8 models have all five ratings · AHRI 21603227857.9(50 is the typical model of its size class)TZP15AY18AJ2Nwith ducted air handler L(E,F)W30BJ4 of 4 models have all five ratings · AHRI 217200644
Ducted, 2 tons78.4(50 is the typical model of its size class)ACIQ-24ZPL-HP230Cwith ducted air handler ACIQ-24CD-HH-MC8 of 8 models have all five ratings · AHRI 21603228179.6(50 is the typical model of its size class) (higher)TZID36H520ZCwith ducted air handler TZID24H520ZA12 of 12 models have all five ratings · AHRI 217495954
Ducted, 2.5–3 tons83.6(50 is the typical model of its size class) (higher)ACIQ-36Z-HH-M5C12 of 12 models have all five ratings · AHRI 21603230258.7(50 is the typical model of its size class)TZP15AY36AJ2Nwith ducted air handler AEW37J+TDR16 of 29 models have all five ratings · AHRI 217200653
Ducted, 3.5–4.5 tons85.1(50 is the typical model of its size class) (higher)ES-48Z-M6C17 of 17 models have all five ratings · AHRI 21603232064.4(50 is the typical model of its size class)TZID60H520ZCwith ducted air handler TZID48H520ZA19 of 37 models have all five ratings · AHRI 217589556
Ducted, 5 tons and up62.5(50 is the typical model of its size class) (higher)ES-55Z-M6C1 of 1 models have all five ratings · AHRI 21603232356.6(50 is the typical model of its size class)TZP15AY60AJ2Nwith ducted air handler TZHDYTST6024*NAN9 of 19 models have all five ratings · AHRI 215415492
Non-ducted, up to 1.5 tons96.2(50 is the typical model of its size class)ACIQ-06ZPL-HP230Cwith ductless indoor unit ACIQ-06W-HH-MD22 of 22 models have all five ratings · AHRI 216032267No models in this size class
Non-ducted, 2 tons76.4(50 is the typical model of its size class)ACIQ-24ZPL-HP230Cwith ductless indoor unit ACIQ-24W-HH-MD6 of 6 models have all five ratings · AHRI 216032271No models in this size class
Non-ducted, 2.5–3 tons78.3(50 is the typical model of its size class)ACIQ-36Z-HH-M5C9 of 9 models have all five ratings · AHRI 216032301No models in this size class
Non-ducted, 3.5–4.5 tons75.6(50 is the typical model of its size class)ACIQ-48Z-HH-M6C6 of 6 models have all five ratings · AHRI 216032304No models in this size class
Non-ducted, 5 tons and up58.6(50 is the typical model of its size class)ES-55Z-M6C1 of 1 models have all five ratings · AHRI 216032322No models in this size class

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
Rating1HVACTHERMAL ZONE
COP at 5°Fbeats 98% · 2.44EZ-18ZPL-HP230BNon-ducted, up to 1.5 tonsbeats 99% · 2.73TZP15AY18AJ2NDucted, up to 1.5 tons
Capacity retention at 5°Fbeats 98% · 126%ACIQ-09ZPL-HP230CNon-ducted, up to 1.5 tonsbeats 100% · 130%TZP15AY18AJ2NDucted, up to 1.5 tons
HSPF2beats 99% · 14.8ACIQ-06ZPL-HP230CNon-ducted, up to 1.5 tonsbeats 74% · 9.7TZID24H520ZCSDucted, 2 tons
SEER2beats 97% · 25.0ES-27Z-M4CNon-ducted, 2.5–3 tonsbeats 87% · 20.0TZID36H520ZCDucted, 2 tons
EER2beats 99% · 18.0ACIQ-06ZPL-HP230CNon-ducted, up to 1.5 tonsbeats 93% · 13.3TZID36H520ZCDucted, 2 tons
Heating capacity at 5°Fbeats 98% · 19,600 Btu/hACIQ-18-HPDDucted, up to 1.5 tonsbeats 99% · 21,000 Btu/hTZP15AY18AJ2NDucted, up to 1.5 tons

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