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      3.5-ton central heat pump · VERSUS

      WeatherKing WP15AY42AJ2N

      Below average cooling and heating efficiency for a 3.5-ton central heat pump, and certified for cold climates.

      Ranks #86 of 138 3.5 ton central heat pumps for cooling efficiency, and costs about $1,308 a year to run in a mixed climate like Atlanta.

      SEER2
      16.0 Cooling efficiency over a season
      Below average · beats 26%
      HSPF2
      8.1 Heating efficiency over a season
      Below average · beats 20%
      EER2
      11.7 Cooling efficiency on a 95°F day
      Average · beats 43%
      Heat at 5°F
      21,000 BTU/h47% of its 47°F output
      Very good · beats 76%

      A good fit if…

      • Your winters get properly cold - it is ENERGY STAR cold-climate certified, with 21,000 BTU/h at 5°F.
      • You want a choice of indoor units - 328 certified pairings.

      Think twice if…

      • 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.

      Calculate my running cost

      Details

      Specifications3.5 ton, R-454B
      General
      BrandWeatherKing
      Also sold asRheem, Ruud, Fujitsu
      Outdoor unit modelWP15AY42AJ2N
      SeriesVERSUS
      TypeCentral heat pump
      Nominal size3.5 ton
      CompressorVariable-speed units run longer at low powerTwo-stage
      RefrigerantR-454B
      Connected (smart) capableNo
      On the market sinceAugust 6, 2024
      Last certifiedSeptember 16, 2026
      Cooling
      SEER2Seasonal efficiency, higher is better16.0 (range 15.2-16.0)
      EER2Efficiency at 95°F outdoors11.7
      Cooling capacity40,000 BTU/h
      Heating
      HSPF2Seasonal efficiency, higher is better7.8-8.1
      Capacity at 47°F40,000 BTU/h
      Capacity at 17°F24,600-40,000 BTU/h
      Capacity at 5°F18,200-21,000 BTU/h
      COP at 5°F2.0 = twice as efficient as a space heater2.00-2.20
      ENERGY STAR cold climateYes
      Heating output as it gets colder47% kept at 5°F

      Every heat pump delivers less heat as the outdoor temperature drops. Certified output of its matchup with TCFY4824STANM at the standard test temperatures, in BTU/h:

      Certified matchups328 indoor units

      The same outdoor unit scores differently with each indoor unit and furnace. The 60 highest-rated of 328 are shown. Ask your installer for the AHRI reference number of the exact system you are quoted.

      Indoor unitFurnaceSEER2EER2HSPF2Heat @5°FAHRI ref.
      TCFY4824STANM · cold climateW802W1255A24UH16.011.78.118,800216545205
      TCFY4821STANM · cold climateW801W0704A17UH16.011.78.119,300216543605
      TCFY4824STANM · cold climateW801W1005A21UHU16.011.78.118,800216543886
      TCFY4821STANM · cold climateW801W1005A21UHU16.011.78.118,800216543522
      RH2TY4824STANN · cold climate-16.011.78.118,200216581278
      RH2TY4824STANN · cold climate-16.011.78.118,200216581279
      FCCN4821SYTA · cold climateFF80SV407017UH16.011.78.119,300216685695
      FCCN4821SYTA · cold climateFF80SV510021UHU16.011.78.118,800216685691
      FCCN4824SYTA · cold climateFF80SV510021UHU16.011.78.118,800216685698
      FCCN4824SYTA · cold climateFF80TV512524UH16.011.78.118,800216685707
      TCFY4824STANMW972W1155A24UPS16.011.78.120,800218728317
      RCFY4824STANMW972W1155A24UPS16.011.78.120,800218728316
      TCFY4824STANMW972W1005A21UPS16.011.78.121,000218728315
      TCFY4821STANMW972W1005A21UPS16.011.78.121,000218728314
      RCFY4824STANMW972W1005A21UPS16.011.78.121,000218728313
      RCFY4821STANMW972W1005A21UPS16.011.78.121,000218728312
      TCFY4824STANMW972W0855A21UPS16.011.78.121,000218728311
      TCFY4821STANMW972W0855A21UPS16.011.78.121,000218728310
      RCFY4824STANMW972W0855A21UPS16.011.78.121,000218728309
      RCFY4821STANMW972W0855A21UPS16.011.78.121,000218728308
      TCFY4824STANMW972W0705A21UPS16.011.78.121,000218728307
      TCFY4821STANMW972W0705A21UPS16.011.78.121,000218728306
      RCFY4824STANMW972W0705A21UPS16.011.78.121,000218728305
      RCFY4821STANMW972W0705A21UPS16.011.78.121,000218728304
      RCFY4824STANMR972V1155A24UPS16.011.78.120,800218728303
      RCFY4824STANMR972V1155A24UPS16.011.78.120,800218728302
      RCFY4824STANMR972V1005A21UPS16.011.78.121,000218728299
      RCFY4824STANMR972V1005A21UPS16.011.78.121,000218728298
      RCFY4821STANMR972V1005A21UPS16.011.78.121,000218728297
      RCFY4821STANMR972V1005A21UPS16.011.78.121,000218728296
      RCFY4824STANMR972V0855A21UPS16.011.78.121,000218728291
      RCFY4824STANMR972V0855A21UPS16.011.78.121,000218728290
      RCFY4821STANMR972V0855A21UPS16.011.78.121,000218728289
      RCFY4821STANMR972V0855A21UPS16.011.78.121,000218728288
      RCFY4824STANMR972V0705A21UPS16.011.78.121,000218728283
      RCFY4824STANMR972V0705A21UPS16.011.78.121,000218728282
      RCFY4821STANMR972V0705A21UPS16.011.78.121,000218728281
      RCFY4821STANMR972V0705A21UPS16.011.78.121,000218728280
      RCFY4821STANM · cold climateR802V0755A21DZ15.211.78.118,800215655133
      TCFY4821STANM · cold climateW801W0755A21UH15.211.78.118,900215655130
      RCFY4824STANM · cold climateR802V1255A24UH15.211.78.118,800215655135
      TCFY4824STANM · cold climateW801W1505A24UH15.211.78.118,800215655139
      RCFY4824STANM · cold climateR802V0755A21DZ15.211.78.118,800215655141
      RCFY4821STANM · cold climateW801W0754A17UH15.211.78.118,800215655143
      RCFY4821STANM · cold climateR802V0754A17UH15.211.78.118,800215655150
      RCFY4824STANM · cold climateR802V1255A24DZ15.211.78.118,700215655151
      RCFY4821STANM · cold climateR801V0754A17UH15.211.78.118,800215655152
      RCFY4821STANM · cold climateR801V0755A21UH15.211.78.118,900215655155
      TCFY4824STANM · cold climateW801W1005A21UHS15.211.78.118,800215655159
      RCFY4824STANM · cold climateR801V1505A24UH15.211.78.118,800215655165
      RCFY4824STANM · cold climateR802V0755A21DZ15.211.78.118,800215655171
      RCFY4824STANM · cold climateR801V1505A24UH15.211.78.118,800215655173
      RCFY4824STANM · cold climateW801W1255A24DZ15.211.78.118,700215655175
      RCFY4821STANM · cold climateR802V0754A17UH15.211.78.118,800215655176
      RCFY4824STANM · cold climateW801W0755A21DZ15.211.78.118,800215655177
      TCFY4821STANM · cold climateW802W0754A17DZ15.211.78.119,300215655178
      RCFY4824STANM · cold climateW802W0755A21UH15.211.78.118,900215655184
      RCFY4824STANM · cold climateR802V1255A24DZ15.211.78.118,700215655183
      RCFY4821STANM · cold climateR801V1005A21UHU15.211.78.118,800215655192
      TCFY4824STANM · cold climateW801W1005A21DZ15.211.78.118,700215655195
      Yearly running cost in 10 large cities$1,175-$3,124

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

      Questions5
      What is the SEER2 rating of the WeatherKing WP15AY42AJ2N?
      The WeatherKing WP15AY42AJ2N is rated at up to 16.0 SEER2 and 11.7 EER2 for cooling and up to 8.1 HSPF2 for heating. The exact figure depends on the indoor unit it is paired with; across its 328 certified matchups SEER2 ranges from 15.2-16.0.
      Is the WeatherKing WP15AY42AJ2N good for cold climates?
      Yes. At least one certified matchup meets the ENERGY STAR cold-climate criteria, delivering up to 21,000 BTU/h at 5°F with a COP of 2.20, so it is still 2.2 times as efficient as electric resistance heat at that temperature.
      How much does the WeatherKing WP15AY42AJ2N cost to run per year?
      At its rated efficiency it costs about $1,175-$3,124 a year in electricity in large U.S. cities, depending on climate and local rates - for example $1,446 in Phoenix and $2,608 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 WeatherKing WP15AY42AJ2N?
      ENERGY STAR lists 328 certified combinations for this outdoor unit. The highest-rated ones use TCFY4824STANM, TCFY4821STANM, RH2TY4824STANN.
      What refrigerant does the WeatherKing WP15AY42AJ2N 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 $1,433/yrYou save $629/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 WeatherKing WP15AY42AJ2N
      3. What it replaces
      4. Price replace the example with your quote
      Heat pump, per year
      $1,433
      Current system, per year
      $2,063
      You save per year
      $629
      Payback
      23.8 years
      Net after 10 years
      -$8,706

      Cooling $880Heating $553Electricity used: 8,957 kWhSaved vs. a minimum-efficiency heat pump: $149

      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 3.5 ton models

      See all 138 3.5 ton central heat pumps, ranked

      Source: ENERGY STAR Certified Heat Pumps (U.S. EPA), certification of September 16, 2026. How we use the data.