All-around best heat pumps by size
Heat pumps that are good at everything, ranked against units their size: half the score is heating (how much heat they keep at 5°F, how efficient they are at 5°F and over a winter), half is cooling (seasonal and hot-day efficiency).
Covers heat pumps sold new today (R-454B and R-32 refrigerant). See older R-410A models · Updated
Showing Ductless, 3.5–4.5 tons (39,000–56,999 Btu/h cooling). What size is my system?
All-around best, ductless 3.5–4.5 tons
Balances heating (5°F output and efficiency, HSPF2) and cooling (SEER2, EER2), each rating against units their size.
562 of 569 models in this size class have all five ratings.
- 1KUMXA421ALG3.5 tons · 42,000 Btu/h · DuctlessCold-climate pick, score 95.9Meets CEE 2025, CEE 2026, CEE Advanced, Xcel CC, DOE CCHP, ENERGY STAR CC
- Heat kept at 5°F
- 100% (Capacity at 5°F vs 47°F)
- Top 10%
- Efficiency at 5°F
- 2.29 (COP at 5°F)
- Top 10%
- Winter efficiency
- 11.0 (HSPF2)
- Top 10%
- Cooling efficiency
- 21.5 (SEER2)
- Good
- Hot-day cooling
- 13.8 (EER2)
- Top 10%
- 2ZRUM048GSS0LG4 tons · 48,000 Btu/h · DuctlessCold-climate pick, score 80.2Meets CEE 2025, CEE 2026, CEE Advanced, Xcel CC, DOE CCHP, ENERGY STAR CC
- Heat kept at 5°F
- 100% (Capacity at 5°F vs 47°F)
- Top 10%
- Efficiency at 5°F
- 2.10 (COP at 5°F)
- Great
- Winter efficiency
- 10.3 (HSPF2)
- Good
- Cooling efficiency
- 23.3 (SEER2)
- Top 10%
- Hot-day cooling
- 13.5 (EER2)
- Top 10%
- 3MXZ-SM48NLHZ***Mitsubishi ElectricAlso listed as PUMY-HL48NKMU, MXZ-SM48NLHZ-4 tons · 48,000 Btu/h · DuctlessCold-climate pick, score 78.4Meets CEE 2025, CEE 2026, Xcel CC, ENERGY STAR CC
- Heat kept at 5°F
- 100% (Capacity at 5°F vs 47°F)
- Top 10%
- Efficiency at 5°F
- 2.00 (COP at 5°F)
- Below the middle
- Winter efficiency
- 11.5 (HSPF2)
- Top 10%
- Cooling efficiency
- 23.0 (SEER2)
- Great
- Hot-day cooling
- 13.1 (EER2)
- Top 10%
- 4KUSXA421Awith ductless indoor unit KNSCB421ALG3.5 tons · 42,000 Btu/h · DuctlessCold-climate pick, score 88.6Meets CEE 2025, CEE 2026, Xcel CC, ENERGY STAR CC
- Heat kept at 5°F
- 91% (Capacity at 5°F vs 47°F)
- Great
- Efficiency at 5°F
- 2.20 (COP at 5°F)
- Top 10%
- Winter efficiency
- 10.8 (HSPF2)
- Great
- Cooling efficiency
- 21.5 (SEER2)
- Good
- Hot-day cooling
- 13.5 (EER2)
- Top 10%
- 5MCY-MUB0488HS2P-ULCarrier (sold as Toshiba Carrier)4 tons · 48,000 Btu/h · DuctlessCold-climate pick, score 70.8Meets CEE 2025, CEE 2026, Xcel CC, ENERGY STAR CC
- Heat kept at 5°F
- 70% (Capacity at 5°F vs 47°F)
- Below the middle
- Efficiency at 5°F
- 2.50 (COP at 5°F)
- Top 10%
- Winter efficiency
- 11.3 (HSPF2)
- Top 10%
- Cooling efficiency
- 24.4 (SEER2)
- Top 10%
- Hot-day cooling
- 13.4 (EER2)
- Top 10%
- 6AVW-48F3DAH2Hisense4 tons · 48,000 Btu/h · DuctlessCold-climate pick, score 94.6Meets CEE 2025, CEE 2026, CEE Advanced, Xcel CC, DOE CCHP
- Heat kept at 5°F
- 100% (Capacity at 5°F vs 47°F)
- Top 10%
- Efficiency at 5°F
- 2.40 (COP at 5°F)
- Top 10%
- Winter efficiency
- 10.8 (HSPF2)
- Great
- Cooling efficiency
- 22.0 (SEER2)
- Good
- Hot-day cooling
- 12.0 (EER2)
- Good
- 7CHV6-RS48URBMHHCooper&Hunter (sold as Cooper & Hunter)4 tons · 48,000 Btu/h · DuctlessCold-climate pick, score 94.6Meets CEE 2025, CEE 2026, CEE Advanced, Xcel CC, DOE CCHP
- Heat kept at 5°F
- 100% (Capacity at 5°F vs 47°F)
- Top 10%
- Efficiency at 5°F
- 2.40 (COP at 5°F)
- Top 10%
- Winter efficiency
- 10.8 (HSPF2)
- Great
- Cooling efficiency
- 22.0 (SEER2)
- Good
- Hot-day cooling
- 12.0 (EER2)
- Good
- 8AOUH42KUAH1with ductless indoor unit AUUH42KUASFujitsu3.5 tons · 42,000 Btu/h · DuctlessCold-climate pick, score 76.7Meets CEE 2025, CEE 2026, Xcel CC, ENERGY STAR CC
- Heat kept at 5°F
- 102% (Capacity at 5°F vs 47°F)
- Top 10%
- Efficiency at 5°F
- 2.02 (COP at 5°F)
- Good
- Winter efficiency
- 10.6 (HSPF2)
- Good
- Cooling efficiency
- 22.0 (SEER2)
- Good
- Hot-day cooling
- 13.0 (EER2)
- Top 10%
- 9MXZ-SM42NLHZ***Mitsubishi ElectricAlso listed as PUMY-HL42NKMU, MXZ-SM42NLHZ-3.5 tons · 42,000 Btu/h · DuctlessCold-climate pick, score 77.6Meets CEE 2025, CEE 2026, Xcel CC, ENERGY STAR CC
- Heat kept at 5°F
- 100% (Capacity at 5°F vs 47°F)
- Top 10%
- Efficiency at 5°F
- 2.00 (COP at 5°F)
- Below the middle
- Winter efficiency
- 11.1 (HSPF2)
- Top 10%
- Cooling efficiency
- 21.5 (SEER2)
- Good
- Hot-day cooling
- 13.4 (EER2)
- Top 10%
- 10KUMXA481ALG4 tons · 48,000 Btu/h · DuctlessCold-climate pick, score 88.0Meets CEE 2025, CEE 2026, CEE Advanced, Xcel CC, DOE CCHP, ENERGY STAR CC
- Heat kept at 5°F
- 100% (Capacity at 5°F vs 47°F)
- Top 10%
- Efficiency at 5°F
- 2.34 (COP at 5°F)
- Top 10%
- Winter efficiency
- 10.5 (HSPF2)
- Good
- Cooling efficiency
- 20.5 (SEER2)
- Below the middle
- Hot-day cooling
- 13.1 (EER2)
- Top 10%
These are certified test ratings, not a recommendation for your home. The right size comes from a load calculation by a contractor.
Want every model’s heating and cooling sub-scores and the all-sizes board? Switch to Advanced
What good looks like: ductless, 3.5–4.5 tons
Capacity at 5°F vs 47°F
Heating power kept at 5°F
How much of its mild-weather heating power the unit still delivers at 5°F.
- Good
- 81%+
- Great
- 90%+
- Top 10%
- 96%+
COP at 5°F
Efficiency on a 5°F day
How much heat the unit makes from each unit of electricity when it is 5°F outside.
- Good
- 2.00+
- Great
- 2.06+
- Top 10%
- 2.11+
HSPF2
Winter-long heating efficiency
Heating efficiency over a whole winter, measured with a federal test.
- Good
- 10.0+
- Great
- 10.6+
- Top 10%
- 11.0+
SEER2
Summer-long cooling efficiency
Cooling efficiency over a whole summer, measured with a federal test.
- Good
- 21.1+
- Great
- 22.0+
- Top 10%
- 23.0+
EER2
Hot-day cooling efficiency
Cooling efficiency on a 95°F afternoon.
- Good
- 11.9+
- Great
- 12.0+
- Top 10%
- 12.5+
Next steps
The advanced view adds the all-sizes boards, each qualifier’s peer percentiles, charts of every model in each size class, and the EER2 and heat output boards.
Open the advanced view