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      2.5-ton central heat pump · 15 SEER2 HP

      WeatherMaker PH5SAN531**AB

      Below average cooling and heating efficiency for a 2.5-ton central heat pump, but not rated for cold climates.

      Ranks #161 of 199 2.5 ton central heat pumps for cooling efficiency, and costs about $974 a year to run in a mixed climate like Atlanta.

      SEER2
      16.0 Cooling efficiency over a season
      Below average · beats 26%
      HSPF2
      8.0 Heating efficiency over a season
      Below average · beats 12%
      EER2
      13.0 Cooling efficiency on a 95°F day
      Very good · beats 89%
      Heat at 5°F
      14,000 BTU/h45% of its 47°F output
      Average · beats 51%

      A good fit if…

      • You want a choice of indoor units - 25 certified pairings.

      Think twice if…

      • You often see nights below 0°F - it is not cold-climate certified.
      • Cooling cost matters most - its SEER2 is below average for central heat pumps.
      • You mainly need heat - its HSPF2 is below average for central heat pumps.
      • Comfort and noise matter - a single-stage compressor runs only full-on or off.

      Calculate my running cost

      Details

      Specifications2.5 ton, R-454B
      General
      BrandWeatherMaker
      Outdoor unit modelPH5SAN531**AB
      Series15 SEER2 HP
      TypeCentral heat pump
      Nominal size2.5 ton
      CompressorVariable-speed units run longer at low powerSingle stage
      RefrigerantR-454B
      Connected (smart) capableNo
      On the market sinceJuly 31, 2025
      Last certifiedSeptember 22, 2026
      Cooling
      SEER2Seasonal efficiency, higher is better16.0 (range 15.2-16.0)
      EER2Efficiency at 95°F outdoors12.0-13.0
      Cooling capacity27,400-29,400 BTU/h
      Heating
      HSPF2Seasonal efficiency, higher is better7.8-8.0
      Capacity at 47°F29,400-30,600 BTU/h
      Capacity at 17°F17,500-18,100 BTU/h
      Capacity at 5°F13,400-14,000 BTU/h
      COP at 5°F2.0 = twice as efficient as a space heater2.00-2.06
      ENERGY STAR cold climateNo
      Heating output as it gets colder45% kept at 5°F

      Every heat pump delivers less heat as the outdoor temperature drops. Certified output of its matchup with FJ5AN*C42L at the standard test temperatures, in BTU/h:

      Certified matchups25 indoor units

      The same outdoor unit scores differently with each indoor unit and furnace. Ask your installer for the AHRI reference number of the exact system you are quoted.

      Indoor unitFurnaceSEER2EER2HSPF2Heat @5°FAHRI ref.
      FJ5AN*C42L-16.013.08.013,400218754747
      FMA5X36**AL-16.013.08.013,700218754074
      FMA5X30**AL-16.013.08.013,700218754073
      FM(C,U)5Z36**AL-16.012.58.013,400218754070
      FM(C,U)5Z30**AL-16.012.58.013,400218754069
      PF5MN*C42L-16.013.08.013,400218754066
      FM(C,U)5S36**AL-15.512.58.013,500218754760
      FM(C,U)5S30**AL-15.512.58.013,500218754759
      CAA**4321AMPG92MSAA60100C**15.512.58.014,000218754199
      CAA**4321AMPG92MSAA60080C**15.512.58.014,000218754198
      CAA**4321AMPG80MSUA60080C**15.512.58.014,000218754190
      CAA**4321AMPG80MSUA48060B**15.512.08.014,000218754189
      CAA**4321AMPG80MS(A,L)A60110C**15.512.58.014,000218754187
      CAA**4321AMPG80MS(A,L)A60090C**15.512.58.014,000218754186
      CAA**3721AMPG92MSAA60100C**15.512.58.014,000218754163
      CAA**3721AMPG92MSAA60080C**15.512.58.014,000218754162
      CAA**3721AMPG80MSUA60080C**15.512.58.014,000218754154
      CAA**3721AMPG80MSUA48060B**15.512.08.014,000218754153
      CAA**3721AMPG80MS(A,L)A60110C**15.512.58.014,000218754151
      CAA**3721AMPG80MS(A,L)A60090C**15.512.58.014,000218754150
      FJ5AN*B30L-15.512.57.813,400218754749
      FEVB0036**+NAVA53601CK-15.512.57.813,400218754405
      FEVA0036**+NAVA53601CK-15.512.57.813,400218754404
      PF5MN*B30L-15.512.57.813,400218754064
      FMA5L30**AL-15.212.08.013,800218754071
      Yearly running cost in 10 large cities$847-$2,348

      At each state's average electricity price and the city's typical heating and cooling hours.

      Questions5
      What is the SEER2 rating of the WeatherMaker PH5SAN531**AB?
      The WeatherMaker PH5SAN531**AB is rated at up to 16.0 SEER2 and 13.0 EER2 for cooling and up to 8.0 HSPF2 for heating. The exact figure depends on the indoor unit it is paired with; across its 25 certified matchups SEER2 ranges from 15.2-16.0.
      Is the WeatherMaker PH5SAN531**AB good for cold climates?
      It is not cold-climate certified: none of its matchups meet the ENERGY STAR cold-climate criteria (a COP of at least 1.75 at 5°F among other limits). In places with frequent sub-zero nights, pick a cold-climate 2.5-ton model.
      How much does the WeatherMaker PH5SAN531**AB cost to run per year?
      At its rated efficiency it costs about $847-$2,348 a year in electricity in large U.S. cities, depending on climate and local rates - for example $1,056 in Phoenix and $1,971 in Minneapolis. The calculator on this page works it out for your city and compares it with your current system.
      Which indoor units work with the WeatherMaker PH5SAN531**AB?
      ENERGY STAR lists 25 certified combinations for this outdoor unit. The highest-rated ones use FJ5AN*C42L, FMA5X36**AL, FMA5X30**AL.
      What refrigerant does the WeatherMaker PH5SAN531**AB use?
      It uses R-454B.

      Running cost and savings

      Pre-filled with this model. Pick your city and what you heat with today; everything else is optional.

      Heat pump $1,054/yrYou save $451/yrSee details ↓
      1. Where you live
      Adjust heating and cooling hours

      Filled in from your city's climate. Change them if you run the system much more or less than usual.

      2. The heat pump WeatherMaker PH5SAN531**AB
      3. What it replaces
      4. Price replace the example with your quote
      Heat pump, per year
      $1,054
      Current system, per year
      $1,505
      You save per year
      $451
      Payback
      24.4 years
      Net after 10 years
      -$6,490

      Cooling $634Heating $420Electricity used: 6,585 kWhSaved vs. a minimum-efficiency heat pump: $103

      Estimates use the unit's rated SEER2 and HSPF2, full-load hours derived from NOAA 1991-2020 degree days, average residential electricity prices from the U.S. EIA (12 months to July 2026) and fuel prices from EIA (2025 for natural gas, week of 2026-10-05 for propane and heating oil). Very cold days that need backup heat are not modelled. Federal minimum for comparison: 14.3 SEER2 / 7.5 HSPF2.

      Similar 2.5 ton models

      See all 199 2.5 ton central heat pumps, ranked

      Source: ENERGY STAR Certified Heat Pumps (U.S. EPA), certification of September 22, 2026. How we use the data.