Skip to content
Rebate.Blue

Proair vs WILLIS: heat pump ratings compared

Against heat pumps of the same size and type, a typical Proair model beats 52% and a typical WILLIS model 63%. WILLIS rates higher overall.

Covers heat pumps sold new today (R-454B and R-32 refrigerant). See older R-410A models · Updated

Proair

52%

of similar heat pumps beaten by its typical model

About average

30 models listed

WILLIS

63%

of similar heat pumps beaten by its typical model

Well above average

29 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°FProair: Beats 49%WILLIS: Beats 44%
  • Heating power kept at 5°FCapacity at 5°F vs 47°FProair: Beats 55%WILLIS: Beats 71%
  • Winter-long heating efficiencyHSPF2Proair: Beats 59%WILLIS: Beats 50%
  • Summer-long cooling efficiencySEER2Proair: Beats 55%WILLIS: Beats 69%
  • Hot-day cooling efficiencyEER2Proair: Beats 44%WILLIS: Beats 72%

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

    Proair
    70%
    WILLIS
    97%

  • Xcel CC

    Proair
    67%
    WILLIS
    97%

  • CEE Advanced

    Proair
    0%
    WILLIS
    10%

  • ENERGY STAR CC

    Proair
    0%
    WILLIS
    86%

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?

Proair

  1. 1PMUL-H6P-60HP-MProair4.5 tons · 52,000 Btu/h · DuctlessKeeps 87% of its heat at 5°FMeets CEE 2025, CEE 2026, Xcel 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
    69.9score / 100
  2. 2PMUL-H6P-48HP-MProair4 tons · 46,000 Btu/h · DuctlessKeeps 99% of its heat at 5°FMeets CEE 2025, CEE 2026, Xcel 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
    68.7score / 100
  3. 3PMUL-A6P-48HP-MProair4 tons · 45,000 Btu/h · DuctlessKeeps 78% of its heat at 5°FMeets CEE 2025, CEE 2026, Xcel 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
    60.1score / 100

WILLIS

  1. 1MZUHW42KR32-OWILLIS3.5 tons · 42,000 Btu/h · DuctlessKeeps 90% of its heat at 5°FMeets CEE 2025, CEE 2026, Xcel CC, ENERGY STAR CC
    Heat kept at 5°F
    90% (Capacity at 5°F vs 47°F)
    Great
    Efficiency at 5°F
    2.10 (COP at 5°F)
    Great
    Seasonal efficiency
    10.0 (HSPF2)
    Below the middle
    66.5score / 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