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      1.5-ton central heat pump · 15 SEER2 HP

      WeatherMaker PH5SAN518**AB

      Below average cooling and heating efficiency for a 1.5-ton central heat pump, but not rated for cold climates.

      Ranks #147 of 170 1.5 ton central heat pumps for cooling efficiency, and costs about $575 a year to run in a mixed climate like Atlanta.

      SEER2
      15.5 Cooling efficiency over a season
      Below average · beats 15%
      HSPF2
      8.0 Heating efficiency over a season
      Below average · beats 12%
      EER2
      12.5 Cooling efficiency on a 95°F day
      Very good · beats 80%
      Heat at 5°F
      8,600 BTU/h46% of its 47°F output
      Average · beats 58%

      A good fit if…

      • You want a choice of indoor units - 36 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

      Specifications1.5 ton, R-454B
      General
      BrandWeatherMaker
      Outdoor unit modelPH5SAN518**AB
      Series15 SEER2 HP
      TypeCentral heat pump
      Nominal size1.5 ton
      CompressorVariable-speed units run longer at low powerSingle stage
      RefrigerantR-454B
      Connected (smart) capableNo
      On the market sinceJanuary 1, 2024
      Last certifiedSeptember 22, 2026
      Cooling
      SEER2Seasonal efficiency, higher is better15.5 (range 15.2-15.5)
      EER2Efficiency at 95°F outdoors11.7-12.5
      Cooling capacity17,400-18,900 BTU/h
      Heating
      HSPF2Seasonal efficiency, higher is better7.8-8.0
      Capacity at 47°F16,400-18,300 BTU/h
      Capacity at 17°F10,500-11,000 BTU/h
      Capacity at 5°F8,200-8,600 BTU/h
      COP at 5°F2.0 = twice as efficient as a space heater1.88-2.10
      ENERGY STAR cold climateNo
      Heating output as it gets colder46% kept at 5°F

      Every heat pump delivers less heat as the outdoor temperature drops. Certified output of its matchup with FMA5X24**AL at the standard test temperatures, in BTU/h:

      Certified matchups36 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.
      FMA5X24**AL-15.512.58.08,200218754042
      CVAMA3217XMAPG80MS(A,L)A48070B**15.512.07.88,200218753944
      CVAMA3217XMAPG80MS(A,L)A36070B**15.512.07.88,200218753943
      FM(C,U)5S30**AL-15.212.08.08,600218754761
      FM(C,U)5Z24**AL-15.212.08.08,500218754052
      FM(C,U)5Z18**AL-15.212.08.08,500218754051
      FJ5AN*B30L-15.212.07.88,400218754740
      FM(C,U)5Z30**AL-15.212.07.88,200218754053
      FMA5X18**AL-15.212.07.88,200218754041
      PF5MN*B30L-15.212.07.88,400218753932
      CAA**2517AMPG96VTAB48060B**15.211.77.88,400218753909
      CAA**2517AMPG95MSUA48060B**15.212.07.88,500218753908
      CAA**2517AMPG96MSAA48080B**15.211.77.88,500218753907
      CAA**2517AMPG92MSAA48080B**15.212.07.88,400218753906
      CAA**2517AMPG92MSAA42060B**15.212.07.88,400218753905
      CAA**2517AMPG80VTLB48070B**15.211.77.88,500218753904
      CAA**2517AMPG80VTLB36070A**15.212.07.88,400218753903
      CAA**2517AMPG80VTLB36045A**15.212.07.88,400218753902
      CAA**2517AMPG80MSUA48060B**15.212.07.88,400218753901
      CAA**2517AMPG80MSUA36040B**15.212.07.88,400218753900
      CAA**2517AMPG80MS(A,L)A42090B**15.212.07.88,400218753899
      CAA**2517AMPG80MS(A,L)A48070B**15.212.07.88,500218753898
      CAA**2517AMPG80MS(A,L)A36070B**15.212.07.88,400218753897
      CAA**2517AMPG80MS(A,L)A36070A**15.212.07.88,400218753896
      CAA**2517AMPG80MS(A,L)A36045A**15.212.07.88,400218753895
      CAA**1917AMPG95MSUA48060B**15.212.07.88,400218753894
      CAA**1917AMPG92MSAA48080B**15.212.07.88,400218753893
      CAA**1917AMPG92MSAA42060B**15.212.07.88,400218753892
      CAA**1917AMPG80VTLB36070A**15.211.77.88,400218753891
      CAA**1917AMPG80MSUA48060B**15.212.07.88,400218753890
      CAA**1917AMPG80MSUA36040B**15.212.07.88,400218753889
      CAA**1917AMPG80MS(A,L)A42090B**15.212.07.88,400218753888
      CAA**1917AMPG80MS(A,L)A48070B**15.212.07.88,400218753887
      CAA**1917AMPG80MS(A,L)A36070B**15.212.07.88,300218753886
      CAA**1917AMPG80MS(A,L)A36070A**15.212.07.88,400218753885
      CAA**1917AMPG80MS(A,L)A36045A**15.212.07.88,400218753884
      Yearly running cost in 10 large cities$547-$1,347

      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 PH5SAN518**AB?
      The WeatherMaker PH5SAN518**AB is rated at up to 15.5 SEER2 and 12.5 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 36 certified matchups SEER2 ranges from 15.2-15.5.
      Is the WeatherMaker PH5SAN518**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 1.5-ton model.
      How much does the WeatherMaker PH5SAN518**AB cost to run per year?
      At its rated efficiency it costs about $547-$1,347 a year in electricity in large U.S. cities, depending on climate and local rates - for example $658 in Phoenix and $1,113 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 PH5SAN518**AB?
      ENERGY STAR lists 36 certified combinations for this outdoor unit. The highest-rated ones use FMA5X24**AL, CVAMA3217XMA, FM(C,U)5S30**AL.
      What refrigerant does the WeatherMaker PH5SAN518**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 $645/yrYou save $266/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 PH5SAN518**AB
      3. What it replaces
      4. Price replace the example with your quote
      Heat pump, per year
      $645
      Current system, per year
      $910
      You save per year
      $266
      Payback
      26.4 years
      Net after 10 years
      -$4,345

      Cooling $411Heating $234Electricity used: 4,030 kWhSaved vs. a minimum-efficiency heat pump: $50

      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 1.5 ton models

      See all 170 1.5 ton central heat pumps, ranked

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