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AIR-CON vs ZERO: heat pump ratings compared
Against heat pumps of the same size and type, a typical AIR-CON model beats 45% and a typical ZERO model 53%. ZERO rates higher overall.
Covers heat pumps sold new today (R-454B and R-32 refrigerant). See older R-410A models · Updated
AIR-CON
45%
of similar heat pumps beaten by its typical model
About average41 models listed
ZERO
53%
of similar heat pumps beaten by its typical model
About average119 models listed
- Efficiency on a 5°F dayCOP at 5°FAIR-CON: Beats 57%ZERO: Beats 45%
- Heating power kept at 5°FCapacity at 5°F vs 47°FAIR-CON: Beats 33%ZERO: Beats 52%
- Winter-long heating efficiencyHSPF2AIR-CON: Beats 45%ZERO: Beats 57%
- Summer-long cooling efficiencySEER2AIR-CON: Beats 43%ZERO: Beats 58%
- Hot-day cooling efficiencyEER2AIR-CON: Beats 39%ZERO: Beats 48%
Average (50%)Dashed outline: the other brand, for comparison
Want ranks, distributions per size class and cold-weather curves? Switch to Advanced
Rebate standards
CEE 2025
- AIR-CON
- 44%
- ZERO
- 71%
Xcel CC
- AIR-CON
- 34%
- ZERO
- 65%
CEE Advanced
- AIR-CON
- 0%
- ZERO
- 0%
ENERGY STAR CC
- AIR-CON
- 0%
- ZERO
- 53%
Top cold-climate picks, ductless 3.5–4.5 tons
Only units that keep at least 70% of their heat at 5°F, ranked on heat kept, efficiency at 5°F and seasonal efficiency (HSPF2), against units their size.
Showing Ductless, 3.5–4.5 tons (39,000–56,999 Btu/h cooling). What size is my system?
AIR-CON
- 1ASGCI8H4M48with ductless indoor unit ASGEC8H4M48AIR-CON4 tons · 48,000 Btu/h · DuctlessKeeps 81% of its heat at 5°FMeets Xcel CC
- Heat kept at 5°F
- 81% (Capacity at 5°F vs 47°F)
- Below the middle
- Efficiency at 5°F
- 2.11 (COP at 5°F)
- Top 10%
- Seasonal efficiency
- 9.9 (HSPF2)
- Below the middle
ZERO
- 1Z4SOV-53HDMB-USHHZERO4.5 tons · 52,000 Btu/h · DuctlessKeeps 87% of its heat at 5°FMeets CEE 2025, CEE 2026, Xcel CC, ENERGY STAR CC
- Heat kept at 5°F
- 87% (Capacity at 5°F vs 47°F)
- Good
- Efficiency at 5°F
- 2.05 (COP at 5°F)
- Good
- Seasonal efficiency
- 10.7 (HSPF2)
- Great
- 2Z4SOV-48HDMB-USHHZERO4 tons · 46,000 Btu/h · DuctlessKeeps 99% of its heat at 5°FMeets CEE 2025, CEE 2026, Xcel CC, ENERGY STAR CC
- Heat kept at 5°F
- 99% (Capacity at 5°F vs 47°F)
- Top 10%
- Efficiency at 5°F
- 2.00 (COP at 5°F)
- Below the middle
- Seasonal efficiency
- 10.6 (HSPF2)
- Good
- 3Z4SOV-48HDMB-USZEROAlso listed as Z6SOV-48HDMB-US4 tons · 45,000 Btu/h · DuctlessKeeps 78% of its heat at 5°FMeets CEE 2025, CEE 2026, Xcel CC, ENERGY STAR CC
- Heat kept at 5°F
- 78% (Capacity at 5°F vs 47°F)
- Below the middle
- Efficiency at 5°F
- 2.10 (COP at 5°F)
- Great
- Seasonal efficiency
- 10.3 (HSPF2)
- Good
These are certified test ratings, not a recommendation for your home. The right size comes from a load calculation by a contractor.
Next steps
The advanced view adds ranks, both brands’ models inside every size class, standout models per rating and cold-weather curves.
Open the advanced view