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First Co. vs WILLIS: heat pump ratings compared

Against heat pumps of the same size and type, a typical First Co. model beats 7% and a typical WILLIS model 51%. WILLIS rates higher overall.

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

First Co.

7%

of similar heat pumps beaten by its typical model

Well below average

16 models listed

WILLIS

51%

of similar heat pumps beaten by its typical model

About average

15 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°FFirst Co.: Beats 16%WILLIS: Beats 39%
  • Heating power kept at 5°FCapacity at 5°F vs 47°FFirst Co.: Beats 9%WILLIS: Beats 64%
  • Winter-long heating efficiencyHSPF2First Co.: Beats 2%WILLIS: Beats 52%
  • Summer-long cooling efficiencySEER2First Co.: Beats 1%WILLIS: Beats 55%
  • Hot-day cooling efficiencyEER2First Co.: Beats 10%WILLIS: 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

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

  • CEE 2025

    First Co.
    0%
    WILLIS
    87%

  • Xcel CC

    First Co.
    0%
    WILLIS
    87%

  • CEE Advanced

    First Co.
    0%
    WILLIS
    0%

  • ENERGY STAR CC

    First Co.
    0%
    WILLIS
    73%

Top cold-climate picks, ducted 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 Ducted, 3.5–4.5 tons (39,000–56,999 Btu/h cooling). What size is my system?

First Co.

No ducted, 3.5–4.5 tons model from First Co..

WILLIS

  1. 1FLEX48/60KUHwith ducted air handler FLEXAH48/60KWILLIS4.5 tons · 54,000 Btu/h · DuctedKeeps 76% of its heat at 5°FMeets CEE 2025, CEE 2026, Xcel CC, ENERGY STAR CC
    Heat kept at 5°F
    76% (Capacity at 5°F vs 47°F)
    Good
    Efficiency at 5°F
    1.80 (COP at 5°F)
    Below the middle
    Seasonal efficiency
    9.0 (HSPF2)
    Good
    56.7score / 100
  2. 2PRT60KUHWILLIS4.5 tons · 56,000 Btu/h · DuctedKeeps 79% of its heat at 5°FMeets Xcel CC, ENERGY STAR CC
    Heat kept at 5°F
    79% (Capacity at 5°F vs 47°F)
    Good
    Efficiency at 5°F
    1.80 (COP at 5°F)
    Below the middle
    Seasonal efficiency
    8.3 (HSPF2)
    Good
    53.0score / 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