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.

COSTWAY and iCongo 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, COSTWAY and iCongo split the 6 ratings 3–3.

COSTWAY
iCongo
Other ranked manufacturers

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

Average peer percentile, raw median and rank among ranked manufacturers
Rating	COSTWAY	iCongo
Efficiency index	46% (higher)median — · 26th ranked	42% (higher)median —
COP at 5°F	57% (higher)median 2.00 · 13th ranked	37% (higher)median 1.82
Capacity retention at 5°F	35%median 70% · 27th ranked	52%median 68%
HSPF2	45%median 9.0 · 18th ranked	49%median 8.4
SEER2	49% (higher)median 20.5 · 18th ranked	48% (higher)median 15.8
EER2	36% (higher)median 11.0 · 29th ranked	28% (higher)median 10.0
Heating capacity at 5°F	39%median 11,600 Btu/h · 26th ranked	55%median 25,200 Btu/h
Outdoor models	47	47
AHRI certifications	48	97

Share of models meeting each standard

Percent of each manufacturer’s models with a qualifying certification
Standard	COSTWAY	iCongo
CEE 2025 Tier 1 (Split ASHP)	63.8%30 models	31.9%15 models
CEE 2026 Tier 1 (Split ASHP)	63.8%30 models	31.9%15 models
CEE Advanced Tier (Split ASHP)	0%0 models	0%0 models
Xcel Energy Colorado cold-climate ASHP (2025)	42.6%20 models	31.9%15 models
DOE Cold Climate Heat Pump Challenge	0%0 models	0%0 models
ENERGY STAR Cold Climate	29.8%14 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

COSTWAY
iCongo
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	COSTWAY	iCongo
Ducted, 2 tons	1 · index 37%	10 · index 43%
Ducted, 2.5–3 tons	4 · index 61%	12 · index 37%
Ducted, 3.5–4.5 tons	2 · index 46%	22 · index 46%
Ducted, up to 1.5 tons	None	3 · index 35%
Non-ducted, up to 1.5 tons	29 · index 41%	None
Non-ducted, 2 tons	9 · index 50%	None
Non-ducted, 2.5–3 tons	3 · index 65%	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 type	COSTWAYCold-climate score, best model	iCongoCold-climate score, best model
Ducted, up to 1.5 tons	No models in this size class	45.5(50 is the typical model of its size class)ZOC-18HIN4-M-SE18with ducted air handler ZVMQFA-18HIN4L-M-SE152 of 3 models qualify · AHRI 217902692
Ducted, 2 tons	42.5(50 is the typical model of its size class)FP11018USwith ducted air handler FP11021US1 of 1 models qualify · AHRI 217169696	70.4(50 is the typical model of its size class) (higher)ZWDA-24HI1N4-M-SE18Also listed as ZWDA-24HI1N4-M-SE189 of 10 models qualify · AHRI 217022533
Ducted, 2.5–3 tons	64.8(50 is the typical model of its size class)FP10982USwith ducted air handler FP10985US4 of 4 models qualify · AHRI 217221416	69.2(50 is the typical model of its size class) (higher)ZOD-36HIN4-M-SE18Hwith ducted air handler ZVMXFB-36HI1N4-C-M-SE183 of 12 models qualify · AHRI 218647967
Ducted, 3.5–4.5 tons	64.7(50 is the typical model of its size class)FP10983USwith ducted air handler FP10986US2 of 2 models qualify · AHRI 217221417	66.1(50 is the typical model of its size class) (higher)ZODA-48HIN4-M-SE18H*with ducted air handler ZVMXFC-48HI1N4-C-M-SE1811 of 22 models qualify · AHRI 218673039
Non-ducted, up to 1.5 tons	79.2(50 is the typical model of its size class)FP10897US-12WHwith ductless indoor unit FP10897US-22WH10 of 29 models qualify · AHRI 215876635	No models in this size class
Non-ducted, 2 tons	77.4(50 is the typical model of its size class)FP10898US-12WHwith ductless indoor unit FP10898US-22WH2 of 9 models qualify · AHRI 217178697	No models in this size class
Non-ducted, 2.5–3 tons	57.5(50 is the typical model of its size class)FP11134US*3 of 3 models qualify · AHRI 218752594	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 type	COSTWAYAll-around score, best model	iCongoAll-around score, best model
Ducted, up to 1.5 tons	No models in this size class	38.9(50 is the typical model of its size class)ZOC-18HIN4-M-SE18with ducted air handler ZVMXFA-18HI1N4-C-M-SE183 of 3 models have all five ratings · AHRI 217022537
Ducted, 2 tons	37.2(50 is the typical model of its size class)FP11018USwith ducted air handler FP11021US1 of 1 models have all five ratings · AHRI 217169696	76.9(50 is the typical model of its size class) (higher)ZOT6P-24HIN4-M-SE20with ducted air handler ZVMXFB-24HI1N4-M-SE2010 of 10 models have all five ratings · AHRI 217902688
Ducted, 2.5–3 tons	67.3(50 is the typical model of its size class) (higher)FP10982USwith ducted air handler FP10985US4 of 4 models have all five ratings · AHRI 217221416	54.1(50 is the typical model of its size class)ZOT6P-36HIN4-M-SE20with ducted air handler ZVMXFB-36HI1N4-M-SE2012 of 12 models have all five ratings · AHRI 217902689
Ducted, 3.5–4.5 tons	54.1(50 is the typical model of its size class)FP10983USwith ducted air handler FP10986US2 of 2 models have all five ratings · AHRI 217221417	65.5(50 is the typical model of its size class) (higher)ZWDA-48HI1N4-M-SE18Also listed as ZWDB-48HI1N4S4-M-SE1822 of 22 models have all five ratings · AHRI 217022535
Non-ducted, up to 1.5 tons	82.9(50 is the typical model of its size class)FP10897US-12WHwith ductless indoor unit FP10897US-22WH24 of 29 models have all five ratings · AHRI 215876635	No models in this size class
Non-ducted, 2 tons	86.5(50 is the typical model of its size class)FP10898US-12WHwith ductless indoor unit FP10898US-22WH8 of 9 models have all five ratings · AHRI 217178697	No models in this size class
Non-ducted, 2.5–3 tons	66.6(50 is the typical model of its size class)FP10840US-WH3 of 3 models have all five ratings · AHRI 216771328	No 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
Rating	COSTWAY	iCongo
COP at 5°F	beats 89% · 2.25FP10897US-12WHNon-ducted, up to 1.5 tons	beats 98% · 2.80ZOT6PA-42HN4-M-SE14.3Ducted, 3.5–4.5 tons
Capacity retention at 5°F	beats 79% · 90%FP10841US-WHNon-ducted, 2 tons	beats 99% · 115%ZOD-36HIN4-M-SE18HDucted, 2.5–3 tons
HSPF2	beats 96% · 10.5FP11135US*Ducted, 2.5–3 tons	beats 87% · 10.1ZOD-36HIN4-M-SE18HDucted, 2.5–3 tons
SEER2	beats 98% · 21.0FP11134US*Ducted, 2.5–3 tons	beats 86% · 19.3ZOT6P-36HIN4-M-SE20Ducted, 2.5–3 tons
EER2	beats 96% · 14.0FP10898US-12WHNon-ducted, 2 tons	beats 81% · 12.5ZOT6P-24HIN4-M-SE20Ducted, 2 tons
Heating capacity at 5°F	beats 86% · 15,000 Btu/hFP10897US-12WHNon-ducted, up to 1.5 tons	beats 100% · 42,500 Btu/hZOD-36HIN4-M-SE18HDucted, 2.5–3 tons

More comparisons

Pick any two manufacturers

COSTWAY vs iCongo heat pumps