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.

AUX and Rheem 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, AUX scores higher on 3 of the 6 ratings.

AUX
Rheem
Other ranked manufacturers

Source: AHRI Directory, NEEP · as of Oct 25, 2026

Average peer percentile, raw median and rank among ranked manufacturers
Rating	AUX	Rheem
Efficiency index	49%median — · 21st ranked	50%median — · 20th ranked
COP at 5°F	60% (higher)median 2.00 · 7th ranked	59% (higher)median 2.05 · 11th ranked
Capacity retention at 5°F	51% (higher)median 75% · 15th ranked	48% (higher)median 63% · 19th ranked
HSPF2	40%median 9.0 · 25th ranked	44%median 7.5 · 22nd ranked
SEER2	48% (higher)median 20.0 · 18th ranked	42% (higher)median 15.2 · 24th ranked
EER2	39%median 11.0 · 27th ranked	41%median 10.6 · 24th ranked
Heating capacity at 5°F	49%median 9,600 Btu/h · 17th ranked	49%median 19,550 Btu/h · 19th ranked
Outdoor models	189	342
AHRI certifications	223	26,697

Share of models meeting each standard

Percent of each manufacturer’s models with a qualifying certification
Standard	AUX	Rheem
CEE 2025 Tier 1 (Split ASHP)	68.3%129 models	36%123 models
CEE 2026 Tier 1 (Split ASHP)	66.1%125 models	34.2%117 models
CEE Advanced Tier (Split ASHP)	1.1%2 models	1.8%6 models
Xcel Energy Colorado cold-climate ASHP (2025)	65.6%124 models	33.9%116 models
DOE Cold Climate Heat Pump Challenge	1.1%2 models	1.8%6 models
ENERGY STAR Cold Climate	34.9%66 models	33.6%115 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 · 8 groups where both have models

AUX
Rheem
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 25, 2026

Models per peer group · efficiency index within the group
Size and duct type	AUX	Rheem
Ducted, up to 1.5 tons	6 · index 60%	33 · index 56%
Ducted, 2 tons	4 · index 59%	35 · index 42%
Ducted, 2.5–3 tons	9 · index 63%	90 · index 46%
Ducted, 3.5–4.5 tons	5 · index 61%	120 · index 49%
Ducted, 5 tons and up	None	32 · index 45%
Non-ducted, up to 1.5 tons	120 · index 46%	39 · index 60%
Non-ducted, 2 tons	33 · index 52%	9 · index 54%
Non-ducted, 2.5–3 tons	22 · index 46%	18 · index 55%
Non-ducted, 3.5–4.5 tons	2 · index 73%	12 · index 49%
Non-ducted, 5 tons and up	None	2 · index 43%

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	AUXCold-climate score, best model	RheemCold-climate score, best model
Ducted, up to 1.5 tons	75.4(50 is the typical model of its size class)ASUM18HPMULO6 of 6 models qualify · AHRI 216032437	93.7(50 is the typical model of its size class) (higher)ML06HP230NEXH-Owith ducted air handler ML06HP230LSDUC-I20 of 33 models qualify · AHRI 215864373
Ducted, 2 tons	62.9(50 is the typical model of its size class)ASUM24HPMULO4 of 4 models qualify · AHRI 216032438	85.9(50 is the typical model of its size class) (higher)ML24HP230NEXH-Owith ducted air handler ML24HP230HSDUC-I16 of 34 models qualify · AHRI 215864380
Ducted, 2.5–3 tons	73.8(50 is the typical model of its size class)ASPR30HPMULO6 of 9 models qualify · AHRI 216032400	94.4(50 is the typical model of its size class) (higher)RD18AY36AJVCwith ducted air handler L(E,G)M36FJ28 of 90 models qualify · AHRI 218029736
Ducted, 3.5–4.5 tons	77.1(50 is the typical model of its size class)ASUM42HPMULO5 of 5 models qualify · AHRI 216032440	95.2(50 is the typical model of its size class) (higher)RD18AY48AJVCwith indoor coil D(A,C,E)60B4J+TDR and furnace R801V0754A17DZ33 of 121 models qualify · AHRI 218827549
Ducted, 5 tons and up	No models in this size class	78.0(50 is the typical model of its size class)RP17AY60AJVCwith indoor coil RCFY6024STANM and furnace R801V1255A24UHNAlso sold as SURE SP17AY60AJVC2 of 32 models qualify · AHRI 218160560
Non-ducted, up to 1.5 tons	83.5(50 is the typical model of its size class)AM2-H18/2DR3BAlso listed as ASUM18HPMULO80 of 120 models qualify · AHRI 214097940	94.9(50 is the typical model of its size class) (higher)ML06HP230NEXH-Owith ductless indoor unit ML06HP2301WYCAS-I30 of 39 models qualify · AHRI 215864386
Non-ducted, 2 tons	84.6(50 is the typical model of its size class)AM3-H24/2DR3BAlso listed as ASUM24HPMULO16 of 33 models qualify · AHRI 214097943	90.0(50 is the typical model of its size class) (higher)ML24HP230NEXH-Owith ductless indoor unit ML24HP230STDCAS-I9 of 9 models qualify · AHRI 215864372
Non-ducted, 2.5–3 tons	73.4(50 is the typical model of its size class)AM4-H36/2DR3BAlso listed as ASUM36HPMULO18 of 22 models qualify · AHRI 214097941	89.3(50 is the typical model of its size class) (higher)ML36HP230LCMH-Owith ductless indoor unit ML36HP230FLO-I15 of 18 models qualify · AHRI 215864403
Non-ducted, 3.5–4.5 tons	60.1(50 is the typical model of its size class)ASUM42HPMULO2 of 2 models qualify · AHRI 216050942	73.6(50 is the typical model of its size class) (higher)ML48HP230MULH-O*Also listed as ML48HP230MULH - O11 of 12 models qualify · AHRI 216623576
Non-ducted, 5 tons and up	No models in this size class	None on this board (0 of 2 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 type	AUXAll-around score, best model	RheemAll-around score, best model
Ducted, up to 1.5 tons	79.8(50 is the typical model of its size class)ASUM18HPMULO6 of 6 models have all five ratings · AHRI 216032437	95.1(50 is the typical model of its size class) (higher)ML06HP230NEXH-Owith ducted air handler ML06HP230LSDUC-I33 of 33 models have all five ratings · AHRI 215864373
Ducted, 2 tons	78.2(50 is the typical model of its size class)ASUM24HPMULO4 of 4 models have all five ratings · AHRI 216032438	78.8(50 is the typical model of its size class) (higher)ML24HP230NEX-Owith ducted air handler ML24HP230HSDUC-I32 of 32 models have all five ratings · AHRI 215864360
Ducted, 2.5–3 tons	81.4(50 is the typical model of its size class)ASUM36HPMULO9 of 9 models have all five ratings · AHRI 216032439	92.7(50 is the typical model of its size class) (higher)RD18AY36AJVCwith ducted air handler L(E,G)M36FJ68 of 91 models have all five ratings · AHRI 218029736
Ducted, 3.5–4.5 tons	87.2(50 is the typical model of its size class) (higher)ASUM42HPMULO5 of 5 models have all five ratings · AHRI 216032440	86.4(50 is the typical model of its size class)RD18AY48AJVCwith ducted air handler L(E,G)M60IJ69 of 116 models have all five ratings · AHRI 218029742
Ducted, 5 tons and up	No models in this size class	70.6(50 is the typical model of its size class)RP17AY60AJVCwith ducted air handler RH2TY6024STANNAlso sold as SURE SP17AY60AJVC24 of 38 models have all five ratings · AHRI 218160613
Non-ducted, up to 1.5 tons	84.2(50 is the typical model of its size class)ASW-H18E3B2/R3DI-D2with ductless indoor unit ASW-H18E3B2/R3DI-D2Also listed as ASW-H18E3B2/**R3DI-D2102 of 120 models have all five ratings · AHRI 215218928	94.4(50 is the typical model of its size class) (higher)ML06HP230NEXH-Owith ductless indoor unit ML06HP230NEX-I38 of 39 models have all five ratings · AHRI 215864338
Non-ducted, 2 tons	87.0(50 is the typical model of its size class) (higher)ASW-H24F6A2/ R3DI-D7with ductless indoor unit ASW-H24F6A2/ R3DI-D7Also listed as ASW-H24F6A2/**R3DI-D729 of 33 models have all five ratings · AHRI 217115274	78.0(50 is the typical model of its size class)ML24HP230CALH-Owith ductless indoor unit ML24HP230CALH-I8 of 8 models have all five ratings · AHRI 215864348
Non-ducted, 2.5–3 tons	78.5(50 is the typical model of its size class)AM4-H36/2DR3BAlso listed as ASUM36HPMULO18 of 22 models have all five ratings · AHRI 214097941	78.6(50 is the typical model of its size class) (higher)ML36HP230MULH-O*Also listed as ML36HP230MULH - O18 of 19 models have all five ratings · AHRI 216623571
Non-ducted, 3.5–4.5 tons	74.4(50 is the typical model of its size class)ASUM42HPMULO2 of 2 models have all five ratings · AHRI 216050942	75.5(50 is the typical model of its size class) (higher)ML48HP230MULH-O*Also listed as ML48HP230MULH - O12 of 12 models have all five ratings · AHRI 216623574
Non-ducted, 5 tons and up	No models in this size class	58.7(50 is the typical model of its size class)ML55HP230MUL-O*2 of 2 models have all five ratings · AHRI 216623550

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	AUX	Rheem
COP at 5°F	beats 100% · 2.52AFEB09HP115V1CONon-ducted, up to 1.5 tons	beats 100% · 3.08RP15AY48AJ2NDucted, 3.5–4.5 tons
Capacity retention at 5°F	beats 99% · 108%AM3-H24/2DR3BAlso listed as ASUM24HPMULONon-ducted, 2 tons	beats 100% · 150%ML06HP230CALH-ONon-ducted, up to 1.5 tons
HSPF2	beats 96% · 11.0AM4-H36/2DR3BAlso listed as ASUM36HPMULONon-ducted, 2.5–3 tons	beats 100% · 15.6ML06HP230CALH-ONon-ducted, up to 1.5 tons
SEER2	beats 100% · 22.0ASUM42HPMULODucted, 3.5–4.5 tons	beats 100% · 35.0ML06HP230CALH-ONon-ducted, up to 1.5 tons
EER2	beats 97% · 14.0AMAR24HP230V1CONon-ducted, 2 tons	beats 99% · 17.4ML06HP230CALH-ONon-ducted, up to 1.5 tons
Heating capacity at 5°F	beats 99% · 21,800 Btu/hAM2-H18/2DR3BAlso listed as ASUM18HPMULONon-ducted, up to 1.5 tons	beats 100% · 35,800 Btu/hRP15AY30AJ2NDucted, 2 tons

In the cold

NEEP cold-climate listings of both manufacturers against all listed models.

AUX vs Rheem: capacity and COP from 47°F downNEEP cold-climate listings at maximum capacity · 6,130 models (45.8% of the catalog) have ratings at 47, 17 and 5°F

All listed models (median, middle 50% and 80%)
AUX (median, middle 50%)
Rheem (median, middle 50%)

One curve per model: its NEEP-rated certification with the best 5°F COP. Every point of a curve is over the same models. NEEP lists only models submitted to it, so this is a cold-climate-leaning subset, not the whole catalog.

Show the data as a table

All listed models: capacity, % of its 47°F maximum
Scope, temperature	Models	10th pct.	25th	Median	75th	90th
All rated models, 47°F	6,130	100%	100%	100%	100%	100%
All rated models, 17°F	6,130	64%	69%	74%	83%	91%
All rated models, 5°F	6,130	57%	61%	69%	77%	83%

All listed models: COP at maximum capacity
Scope, temperature	Models	10th pct.	25th	Median	75th	90th
All rated models, 47°F	6,130	2.8	3.01	3.24	3.48	3.66
All rated models, 17°F	6,130	2	2.14	2.3	2.42	2.61
All rated models, 5°F	6,130	1.8	1.87	2	2.1	2.24

AUX: capacity, % of its 47°F maximum
Scope, temperature	Models	10th pct.	25th	Median	75th	90th
AUX, 47°F	65	100%	100%	100%	100%	100%
AUX, 17°F	65	67%	70%	73%	79%	85%
AUX, 5°F	65	62%	65%	70%	73%	83%

AUX: COP at maximum capacity
Scope, temperature	Models	10th pct.	25th	Median	75th	90th
AUX, 47°F	65	2.93	3.18	3.3	3.52	3.72
AUX, 17°F	65	2.1	2.17	2.28	2.34	2.45
AUX, 5°F	65	1.89	2	2	2.1	2.18

Rheem: capacity, % of its 47°F maximum
Scope, temperature	Models	10th pct.	25th	Median	75th	90th
Rheem, 47°F	118	100%	100%	100%	100%	100%
Rheem, 17°F	118	63%	67%	73%	82%	90%
Rheem, 5°F	118	57%	62%	70%	79%	85%

Rheem: COP at maximum capacity
Scope, temperature	Models	10th pct.	25th	Median	75th	90th
Rheem, 47°F	118	2.87	2.97	3.17	3.44	3.61
Rheem, 17°F	118	2.11	2.24	2.38	2.48	2.61
Rheem, 5°F	118	1.9	2	2	2.1	2.22

Source: NEEP ccASHP list · as of Oct 25, 2026

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AUX vs Rheem heat pumps