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J-KU vs Relief Sciences: heat pump ratings compared

Against heat pumps of the same size and type, a typical J-KU model beats 62% and a typical Relief Sciences model 66%. Relief Sciences rates slightly higher overall.

Covers older R-410A heat pumps, no longer installed new. See models sold today · Updated

J-KU

62%

of similar heat pumps beaten by its typical model

Well above average

10 models listed

Relief Sciences

66%

of similar heat pumps beaten by its typical model

Well above average

10 models listed

Rating by ratingEach bar is the share of same-size, same-type heat pumps that a typical model beats, so the two brands compare fairly even if they make different sizes.
  • Efficiency on a 5°F dayCOP at 5°FJ-KU: Beats 49%Relief Sciences: Beats 38%
  • Heating power kept at 5°FCapacity at 5°F vs 47°FJ-KU: Beats 66%Relief Sciences: Beats 72%
  • Winter-long heating efficiencyHSPF2J-KU: Beats 48%Relief Sciences: Beats 73%
  • Summer-long cooling efficiencySEER2J-KU: Beats 67%Relief Sciences: Beats 76%
  • Hot-day cooling efficiencyEER2J-KU: Beats 71%Relief Sciences: Beats 67%

Average (50%)Dashed outline: the other brand, for comparison

Want ranks, distributions per size class and cold-weather curves? Switch to Advanced

Rebate standards

Share of each brand’s models that meet the level. Programs can have other rules too.
  • CEE 2025

    J-KU
    100%
    Relief Sciences
    100%
  • Xcel CC

    J-KU
    90%
    Relief Sciences
    90%
  • CEE Advanced

    J-KU
    0%
    Relief Sciences
    0%
  • ENERGY STAR CC

    J-KU
    80%
    Relief Sciences
    0%

Top cold-climate picks, ductless up to 1.5 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.

J-KU

  1. 1JKS09HP230V1XCwith ductless indoor unit JKS09HP230V1XEJ-KU1 ton · 9,000 Btu/h · DuctlessKeeps 88% of its heat at 5°FMeets CEE 2025, CEE 2026, Xcel CC, ENERGY STAR CC
    Heat kept at 5°F
    88% (Capacity at 5°F vs 47°F)
    Good
    Efficiency at 5°F
    2.36 (COP at 5°F)
    Top 10%
    Seasonal efficiency
    10.5 (HSPF2)
    Great
    83.4score / 100
  2. 2JKS12HP230V1XCwith ductless indoor unit JKS12HP230V1XEJ-KU1 ton · 12,000 Btu/h · DuctlessKeeps 93% of its heat at 5°FMeets CEE 2025, CEE 2026, Xcel CC, ENERGY STAR CC
    Heat kept at 5°F
    93% (Capacity at 5°F vs 47°F)
    Great
    Efficiency at 5°F
    2.41 (COP at 5°F)
    Top 10%
    Seasonal efficiency
    9.8 (HSPF2)
    Good
    80.0score / 100
  3. 3JKS-18H2HP-M2OJ-KU1.5 tons · 18,000 Btu/h · DuctlessKeeps 100% of its heat at 5°FMeets CEE 2025, CEE 2026, Xcel CC, ENERGY STAR CC
    Heat kept at 5°F
    100% (Capacity at 5°F vs 47°F)
    Great
    Efficiency at 5°F
    1.84 (COP at 5°F)
    Below the middle
    Seasonal efficiency
    9.5 (HSPF2)
    Good
    60.5score / 100

Relief Sciences

  1. 1LANG09OD25-1with ductless indoor unit LANG09ID-25Relief Sciences1 ton · 9,000 Btu/h · DuctlessKeeps 86% of its heat at 5°FMeets CEE 2025, CEE 2026, Xcel CC
    Heat kept at 5°F
    86% (Capacity at 5°F vs 47°F)
    Good
    Efficiency at 5°F
    2.22 (COP at 5°F)
    Great
    Seasonal efficiency
    11.6 (HSPF2)
    Top 10%
    86.0score / 100
  2. 2LANG12OD25-1with ductless indoor unit LANG12ID-25Relief Sciences1 ton · 12,000 Btu/h · DuctlessKeeps 74% of its heat at 5°FMeets CEE 2025, CEE 2026, Xcel CC
    Heat kept at 5°F
    74% (Capacity at 5°F vs 47°F)
    Good
    Efficiency at 5°F
    2.25 (COP at 5°F)
    Top 10%
    Seasonal efficiency
    10.8 (HSPF2)
    Great
    77.8score / 100
  3. 3LANG12OD35-1with ductless indoor unit LANG12ID-25Relief Sciences1 ton · 12,000 Btu/h · DuctlessKeeps 101% of its heat at 5°FMeets CEE 2025, CEE 2026, Xcel CC
    Heat kept at 5°F
    101% (Capacity at 5°F vs 47°F)
    Top 10%
    Efficiency at 5°F
    1.90 (COP at 5°F)
    Below the middle
    Seasonal efficiency
    10.5 (HSPF2)
    Great
    73.5score / 100

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