Legacy Systems heat pump efficiency: 46 outdoor models compared

Legacy Systems has 46 heat pump outdoor models certified with this refrigerant group, in 4,062 AHRI-certified combinations. Each model is compared with models of the same size and duct type, so the scores below do not depend on which sizes Legacy Systems makes. Legacy Systems has no QMID (IRS Qualified Manufacturer ID) on file, so it is not ranked against other manufacturers.

New to heat pump ratings? The Simple view explains them in plain words →

ManufacturerData as of Oct 11, 2026updated Oct 11, 2026 · sources

Outdoor models: 46
AHRI certifications: 4,062
Efficiency index: 39%; Typical model vs same-size, same-type peers (32 models)
Meet CEE 2025: 6.5%; 3 models

How Legacy Systems compares with comparable models

For each rating: the share of same-size, same-type models that a typical model of this manufacturer beats (50% is typical), its rank, and the raw median for context. Raw medians are not comparable across manufacturers that make different sizes.

Legacy Systems against every ranked manufacturerPeer scores, 0–100 · grey ticks: each ranked manufacturer · shaded: the middle half of Legacy Systems’s own modelsLegacy Systems is strongest on EER2 (its typical model beats 66% of comparable models) and weakest on heating capacity at 5°F (12%).

Legacy Systems
Middle half of its models
Other ranked manufacturers

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

Average peer percentile of Legacy Systems’s models
Rating	Beats comparable models	Rank	Raw median
Efficiency index32 models scored	39%	Not ranked	—
COP at 5°F33 models scored	39%	Not ranked	1.90
Capacity retention at 5°F32 models scored	13%	Not ranked	46%
HSPF246 models scored	21%	Not ranked	7.0
SEER246 models scored	30%	Not ranked	15.2
EER246 models scored	66%	Not ranked	11.4
Heating capacity at 5°F32 models scored	12%	Not ranked	14,800 Btu/h

Standards met

Share of Legacy Systems’s models with at least one qualifying certification
Standard	Share	Models
CEE 2025 Tier 1 (Split ASHP)	6.5%	3
CEE 2026 Tier 1 (Split ASHP)	2.2%	1
CEE Advanced Tier (Split ASHP)	0%	0
Xcel Energy Colorado cold-climate ASHP (2025)	0%	0
DOE Cold Climate Heat Pump Challenge	0%	0
ENERGY STAR Cold Climate	0%	0

Sizes and duct types offered

Models per peer group, and how they score against the other models of that group.

Legacy Systems’s models inside each size and duct typeShape: every model of the group · blue: the middle half of this manufacturer’s models there, median dot, 10th–90th percentile line

Legacy Systems (median, middle 50%, 10th–90th)
All models of the group

Source: AHRI Directory · as of Oct 11, 2026

Share of comparable models beaten, per peer group
Size and duct type	Models	Index	COP@5°F	HSPF2	SEER2
Ducted, up to 1.5 tons	3	35%	41%	12%	22%
Ducted, 2 tons	8	37%	32%	20%	28%
Ducted, 2.5–3 tons	15	38%	43%	19%	26%
Ducted, 3.5–4.5 tons	18	42%	36%	25%	36%
Ducted, 5 tons and up	2	36%	56%	16%	30%

Every Legacy Systems model in the market

Legacy Systems’s 46 models with a known size and duct type, over the shape of the whole catalog.

Legacy Systems models by size and ratingColoured: Legacy Systems · grey shapes: all 11,475 models · lines: catalog medians by size

Legacy Systems models
Ducted median by size
Non-ducted median by size
Every model at each size (width = count)
Standard threshold

Dots: 46 legacy systems models, each through its representative certification, in the colour of the rating shown. The grey shapes count all 11,475 models, half a ton at a time.

Show the data as a table

COP at 5°F by size and duct type (every model, by rated cooling capacity)
Duct type, size	Models	10th pct.	25th	Median	75th	90th
Ducted, 0.5 tons	175	1.70	1.85	1.90	2.10	2.26
Ducted, 1 ton	340	1.85	1.90	2.00	2.40	2.65
Ducted, 1.5 tons	789	1.75	1.85	2.00	2.20	2.55
Ducted, 2 tons	782	1.73	1.80	2.00	2.10	2.33
Ducted, 2.5 tons	735	1.71	1.80	1.90	2.09	2.48
Ducted, 3 tons	652	1.68	1.70	1.90	2.06	2.36
Ducted, 3.5 tons	641	1.61	1.80	1.95	2.20	2.50
Ducted, 4 tons	367	1.70	1.80	1.91	2.02	2.52
Ducted, 4.5 tons	544	1.70	1.80	1.91	2.08	2.34
Ducted, 5 tons	25	1.80	1.80	1.90	1.90	2.15
Non-ducted, 0.5 tons	717	1.75	1.81	1.97	2.10	2.19
Non-ducted, 1 ton	1,064	1.75	1.80	1.90	2.07	2.25
Non-ducted, 1.5 tons	886	1.80	1.80	1.87	2.07	2.21
Non-ducted, 2 tons	564	1.80	1.80	1.83	2.04	2.21
Non-ducted, 2.5 tons	275	1.80	1.81	1.84	1.86	2.03
Non-ducted, 3 tons	502	1.80	1.80	1.90	2.00	2.09
Non-ducted, 3.5 tons	70	1.82	1.83	1.90	2.00	2.28
Non-ducted, 4 tons	263	1.80	1.80	1.98	2.00	2.10
Non-ducted, 4.5 tons	103	1.77	1.77	1.80	1.97	2.02
Non-ducted, 5 tons	29	1.98	2.00	2.10	2.30	2.47

Source: AHRI Directory · as of Oct 11, 2026

Top Legacy Systems models

Its top five cold-climate picks and its top five all-around models across sizes (both scores compare each model with models of its own size and duct type, so sizes compare), then, on each single rating, the model that beats the largest share of comparable models.

Cold-climate picks

No Legacy Systems model keeps at least 70% of its heat at 5°F with all three cold-climate ratings.

All-around best

Top 5 Legacy Systems models on the all-around score across sizes. 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.
# · Outdoor model	Size · type	Cap. 5/47	COP@5°F	HSPF2	SEER2	EER2	Meets	Combos	AHRI ref.	Compared with	Score	Heating half	Cooling half	Cold-climate score
1GSZC704810ALegacy Systems · GSZC7with ducted air handler CAPT49614A+MBVC2001*-1A	4 tons47,000 Btu/h · Ducted	46%	2.00	8.2	17.2	12.5	CEE 25	47	215236378	Ducted, 3.5–4.5 tons	68.2	46.7	89.7	Not a pick
2GSZC703610ALegacy Systems · GSZC7with ducted air handler CAPTA42304A+MBVC2001*-1A	3 tons34,800 Btu/h · Ducted	50%	2.00	8.2	17.2	12.5	CEE 25CEE 26	71	215236306	Ducted, 2.5–3 tons	64.2	44.7	83.7	Not a pick
3GSZH506010ALegacy Systems · GSZH5with ducted air handler CAPT49614A+MBVC2001*-1A	4.5 tons54,500 Btu/h · Ducted	38%	2.20	7.8	16.0	12.0	None	53	215237819	Ducted, 3.5–4.5 tons	61.4	42.9	79.8	Not a pick
4GSZC702410A*Legacy Systems · GSZC7with ducted air handler AMVT30BP1400A	2 tons23,800 Btu/h · Ducted	47%	2.00	8.2	17.2	12.5	CEE 25	59	215236246	Ducted, 2 tons	59.1	38.0	80.2	Not a pick
5GSZH503610ALegacy Systems · GSZH5with ducted air handler CAPTA42304A+MBVC1601*-1A	3 tons34,200 Btu/h · Ducted	52%	2.00	7.8	16.0	12.5	None	346	215237327	Ducted, 2.5–3 tons	58.4	41.0	75.9	Not a pick

Best model on each rating

Legacy Systems’s model with the highest peer percentile on each rating, ranked by that one rating only
Rating	Model	Value	Compared with	Beats	AHRI ref.
COP at 5°F	GPHH56041A*	2.51	Ducted, 5 tons and up	94%	215233043
Capacity retention at 5°F	GPHH56041A*	42%	Ducted, 5 tons and up	28%	215233043
HSPF2	GSZC704810A*	8.2	Ducted, 3.5–4.5 tons	55%	215236376
SEER2	GSZC704810A*	17.2	Ducted, 3.5–4.5 tons	81%	215236376
EER2	GSZB404810A*	12.5	Ducted, 3.5–4.5 tons	92%	215236122
Heating capacity at 5°F	GSZC706010A*	30,000 Btu/h	Ducted, 3.5–4.5 tons	38%	215236444

All 46 Legacy Systems models in Explore

Legacy Systems size class by size class: cold-climate and all-around

Its best model on each board in every size and duct type it makes. Both scores are 0–100 against every model of that size class (the line on each bar is 50, the typical model there). Cold-climate picks must keep at least 70% of their heat at 5°F; the all-around score needs all five ratings and has no such bar.

Legacy Systems: best cold-climate pick and best all-around model per size and duct type, with how many of its models are on each board (top 5 and 5 per class are in the snapshot)
Size and duct type	Cold-climate pickCold-climate score, best model	All-around bestAll-around score, best model
Ducted, up to 1.5 tons	None on this board (0 of 3 models qualify)	40.0(50 is the typical model of its size class)GSZB401810Awith ducted air handler CAPTA36264A+MBVC1201*-1AAlso listed as GSZM401810A3 of 3 models have all five ratings · AHRI 215234904
Ducted, 2 tons	None on this board (0 of 8 models qualify)	59.1(50 is the typical model of its size class)GSZC702410A*with ducted air handler AMVT30BP1400A6 of 8 models have all five ratings · AHRI 215236246
Ducted, 2.5–3 tons	None on this board (0 of 15 models qualify)	64.2(50 is the typical model of its size class)GSZC703610Awith ducted air handler CAPTA42304A+MBVC2001*-1A11 of 15 models have all five ratings · AHRI 215236306
Ducted, 3.5–4.5 tons	None on this board (0 of 18 models qualify)	68.2(50 is the typical model of its size class)GSZC704810Awith ducted air handler CAPT49614A+MBVC2001*-1A11 of 18 models have all five ratings · AHRI 215236378
Ducted, 5 tons and up	None on this board (0 of 2 models qualify)	51.5(50 is the typical model of its size class)GPHH56041A*2 of 2 models have all five ratings · AHRI 215233043

All-around board, every manufacturer

Newest Legacy Systems certifications

By AHRI reference number; AHRI issues references in increasing order.

The 5 most recently certified Legacy Systems outdoor models
Outdoor model	Size · type	COP@5°F	Cap. 5/47	HSPF2	SEER2	Meets	Combos	AHRI ref.
GSZM403610ALegacy Systems · GSZM4with indoor coil CAPTA42304B and furnace GM9S960805CNA	3 tons34,400 Btu/h · Ducted	1.90	51%	7.5	14.3	None	134	215238971
GSZM403010ALegacy Systems · GSZM4with indoor coil CAFA42266B+TXV and furnace GM9C960804CNA	2.5 tons27,600 Btu/h · Ducted	2.00	53%	7.5	14.3	None	160	215238835
GSZM402410ALegacy Systems · GSZM4with indoor coil CAPTA30264B and furnace G*VS960603BUA	2 tons22,600 Btu/h · Ducted	1.80	51%	7.5	14.3	None	377	215238660
GSZM401810ALegacy Systems · GSZM4with indoor coil CAPTA30224B and furnace GM9S960403BUA	1.5 tons17,000 Btu/h · Ducted	1.80	48%	7.5	14.3	None	334	215238243
GSZH506010A*Legacy Systems · GSZH5with indoor coil CHPT4860D4A and furnace GM9C961205DNA	4.5 tons53,500 Btu/h · Ducted	2.20	38%	7.5	15.0	None	53	215237879

Shares hardware with

Manufacturers whose models are the same equipment under another badge. About OEM families

No shared hardware found for Legacy Systems in this group.

Compare Legacy Systems

Manufacturers of a similar size, side by side.

Compare with any manufacturer

Legacy Systems includes these brand names as listed in AHRI: Legacy Systems. Standards are checked against published thresholds; program rules beyond ratings are not checked.