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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 55% and a typical ZERO model 49%. AIR-CON rates higher overall.
Covers older R-410A heat pumps, no longer installed new. See models sold today · Updated
AIR-CON
55%
of similar heat pumps beaten by its typical model
About average65 models listed
ZERO
49%
of similar heat pumps beaten by its typical model
About average69 models listed
- Efficiency on a 5°F dayCOP at 5°FAIR-CON: Beats 47%ZERO: Beats 48%
- Heating power kept at 5°FCapacity at 5°F vs 47°FAIR-CON: Beats 52%ZERO: Beats 43%
- Winter-long heating efficiencyHSPF2AIR-CON: Beats 46%ZERO: Beats 46%
- Summer-long cooling efficiencySEER2AIR-CON: Beats 54%ZERO: Beats 53%
- Hot-day cooling efficiencyEER2AIR-CON: Beats 50%ZERO: Beats 46%
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
- 55%
- ZERO
- 59%
Xcel CC
- AIR-CON
- 49%
- ZERO
- 48%
CEE Advanced
- AIR-CON
- 0%
- ZERO
- 0%
ENERGY STAR CC
- AIR-CON
- 39%
- ZERO
- 25%
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
- 1AMSCI4H4S42AIR-CON3.5 tons · 42,000 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
- 1.84 (COP at 5°F)
- Below the middle
- Seasonal efficiency
- 9.0 (HSPF2)
- Below the middle
ZERO
- 1Z5SOV-48HDM-USZERO4 tons · 48,000 Btu/h · DuctlessKeeps 92% of its heat at 5°FMeets CEE 2025, CEE 2026, Xcel CC, ENERGY STAR CC
- Heat kept at 5°F
- 92% (Capacity at 5°F vs 47°F)
- Great
- Efficiency at 5°F
- 2.00 (COP at 5°F)
- Good
- Seasonal efficiency
- 10.0 (HSPF2)
- Great
- 2ZSOV-48HDM-USwith ductless indoor unit ZEV-48HDM-USZERO4 tons · 48,000 Btu/h · DuctlessKeeps 70% of its heat at 5°FMeets 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
- 1.85 (COP at 5°F)
- Below the middle
- Seasonal efficiency
- 10.0 (HSPF2)
- Great
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