What is the SEER2 rating of the ECOTEMP W5H5S42*K*AAA?

The ECOTEMP W5H5S42*K*AAA is rated at up to 15.5 SEER2 and 13.0 EER2 for cooling and up to 7.8 HSPF2 for heating. The exact figure depends on the indoor unit it is paired with; across its 6 certified matchups SEER2 ranges from 15.2-15.5.

Is the ECOTEMP W5H5S42*K*AAA 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 3.5-ton model.

How much does the ECOTEMP W5H5S42*K*AAA cost to run per year?

At its rated efficiency it costs about $1,286-$3,312 a year in electricity in large U.S. cities, depending on climate and local rates - for example $1,568 in Phoenix and $2,753 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 ECOTEMP W5H5S42*K*AAA?

ENERGY STAR lists 6 certified combinations for this outdoor unit. The highest-rated ones use WCGL605*D, WCHL605*D, FEVB0060**+NAVA56001CK.

3.5-ton central heat pump · 15 SEER2 HP

ECOTEMP W5H5S42KAAA

Below average cooling and heating efficiency for a 3.5-ton central heat pump, but not rated for cold climates.

Ranks #107 of 138 3.5 ton central heat pumps for cooling efficiency, and costs about $1,398 a year to run in a mixed climate like Atlanta.

SEER2: 15.5 Cooling efficiency over a season
Below average · beats 15%
HSPF2: 7.8 Heating efficiency over a season
Below average · beats 5%
EER2: 13.0 Cooling efficiency on a 95°F day
Very good · beats 89%
Heat at 5°F: 19,900 BTU/h49% of its 47°F output
Very good · beats 83%

A good fit if…

You want a certified 3.5-ton central heat pump at a typical efficiency level.

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

Specifications3.5 ton, R-454B

General
Brand	ECOTEMP
Also sold as	Grandaire
Outdoor unit model	W5H5S42KAAA
Series	15 SEER2 HP
Type	Central heat pump
Nominal size	3.5 ton
CompressorVariable-speed units run longer at low power	Single stage
Refrigerant	R-454B
Connected (smart) capable	No
On the market since	January 1, 2024
Last certified	February 10, 2026
Cooling
SEER2Seasonal efficiency, higher is better	15.5 (range 15.2-15.5)
EER2Efficiency at 95°F outdoors	11.7-13.0
Cooling capacity	41,500-43,000 BTU/h
Heating
HSPF2Seasonal efficiency, higher is better	7.8
Capacity at 47°F	39,000-40,500 BTU/h
Capacity at 17°F	24,600-25,600 BTU/h
Capacity at 5°F	19,000-19,900 BTU/h
COP at 5°F2.0 = twice as efficient as a space heater	2.20-2.26
ENERGY STAR cold climate	No

Heating output as it gets colder49% kept at 5°F

Every heat pump delivers less heat as the outdoor temperature drops. Certified output of its matchup with WCGL605*D at the standard test temperatures, in BTU/h:

Certified matchups6 indoor units

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

Indoor unit	SEER2	EER2	HSPF2	Heat @5°F	AHRI ref.
WCGL605*D	15.5	13.0	7.8	19,000	214180070
WCGL605*D	15.5	13.0	7.8	19,000	214180071
WCHL605*D	15.2	11.7	7.8	19,900	214180029
WCHL605*D	15.2	11.7	7.8	19,900	214180028
FEVB0060**+NAVA56001CK	15.2	12.5	7.8	19,800	214277454
FEVB0060**+NAVA56001CK	15.2	12.5	7.8	19,800	214277455

Yearly running cost in 10 large cities$1,286-$3,312

Phoenix, AZ$1,568/yr
Miami, FL$1,286/yr
Houston, TX$1,405/yr
Atlanta, GA$1,398/yr
Los Angeles, CA$1,355/yr
New York, NY$3,312/yr
Chicago, IL$2,683/yr
Denver, CO$2,226/yr
Seattle, WA$1,364/yr
Minneapolis, MN$2,753/yr

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

Questions5

What is the SEER2 rating of the ECOTEMP W5H5S42*K*AAA?: The ECOTEMP W5H5S42*K*AAA is rated at up to 15.5 SEER2 and 13.0 EER2 for cooling and up to 7.8 HSPF2 for heating. The exact figure depends on the indoor unit it is paired with; across its 6 certified matchups SEER2 ranges from 15.2-15.5.
Is the ECOTEMP W5H5S42*K*AAA 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 3.5-ton model.
How much does the ECOTEMP W5H5S42*K*AAA cost to run per year?: At its rated efficiency it costs about $1,286-$3,312 a year in electricity in large U.S. cities, depending on climate and local rates - for example $1,568 in Phoenix and $2,753 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 ECOTEMP W5H5S42*K*AAA?: ENERGY STAR lists 6 certified combinations for this outdoor unit. The highest-rated ones use WCGL605*D, WCHL605*D, FEVB0060**+NAVA56001CK.
What refrigerant does the ECOTEMP W5H5S42*K*AAA 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 $1,547/yrYou save $612/yrSee details ↓

1. Where you live

StateCityElectricity ¢ per kWh

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.

Cooling hours full-load hours per yearHeating hours full-load hours per year

2. The heat pump ECOTEMP W5H5S42*K*AAA

Find a model (fills in the ratings below)

SEER2 cooling efficiencyHSPF2 heating efficiencyCooling capacity BTU/hHeating capacity BTU/h

3. What it replaces

Current heatingFurnace efficiency (AFUE %)Gas price, $/thermCurrent coolingOld AC rating SEER2 (10 ≈ 15+ years old)

4. Price replace the example with your quote

Installed price, $Rebates and incentives, $ utility, state

Heat pump, per year: $1,547
Current system, per year: $2,159
You save per year: $612
Payback: 26.1 years
Net after 10 years: -$9,880

Cooling $965Heating $582Electricity used: 9,667 kWhSaved vs. a minimum-efficiency heat pump: $104

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

Carrier 27SCA542A**3015.5 SEER2 · 7.8 HSPF2
Heil N5H5S42*K*AAA15.5 SEER2 · 7.8 HSPF2
Bryant PH5SAN542**AA15.5 SEER2 · 7.8 HSPF2
Kenmore B5H6S42*K*AAA15.5 SEER2 · 7.8 HSPF2
Bryant GH5SAN542**AA15.5 SEER2 · 7.8 HSPF2
Tempstar T5H6S42*K*AAA15.5 SEER2 · 7.8 HSPF2
Bryant 235SAN042**AA15.5 SEER2 · 7.8 HSPF2
MRCOOL MHP17042A-**A15.4 SEER2 · 7.8 HSPF2

See all 138 3.5 ton central heat pumps, ranked

Source: ENERGY STAR Certified Heat Pumps (U.S. EPA), certification of February 10, 2026. How we use the data.