HVAC Rated

3-ton central heat pump · AU Series

AI AIR CONDITIONING AUO18-36N1-M3H

Below average cooling efficiency and very good heating efficiency for a 3-ton central heat pump, and certified for cold climates.

Ranks #206 of 302 3 ton central heat pumps for cooling efficiency, and costs about $1,101 a year to run in a mixed climate like Atlanta.

SEER2
16.3 Cooling efficiency over a season
Below average · beats 37%
HSPF2
9.5 Heating efficiency over a season
Very good · beats 70%
EER2
11.7 Cooling efficiency on a 95°F day
Average · beats 43%
Heat at 5°F
38,000 BTU/h97% of its 47°F output
Below average · beats 5%

A good fit if…

  • Your winters get properly cold - it is ENERGY STAR cold-climate certified, with 38,000 BTU/h at 5°F.
  • It will heat most of the year - its HSPF2 beats 70% of central heat pumps.
  • You want steady temperatures and quiet running - the compressor varies its speed.

Think twice if…

  • Cooling cost matters most - its SEER2 is below average for central heat pumps.
  • You want the newest refrigerant - it uses R-410A, which is being phased down.

Calculate my running cost

Details

Specifications3 ton, R-410A
General
BrandAI AIR CONDITIONING
Outdoor unit modelAUO18-36N1-M3H
SeriesAU Series
TypeCentral heat pump
Nominal size3 ton
CompressorVariable-speed units run longer at low powerContinuously variable
RefrigerantR-410A
Connected (smart) capableNo
On the market sinceMay 20, 2024
Last certifiedJune 9, 2026
Cooling
SEER2Seasonal efficiency, higher is better16.3 (range 16.3)
EER2Efficiency at 95°F outdoors11.7
Cooling capacity35,000 BTU/h
Heating
HSPF2Seasonal efficiency, higher is better9.5
Capacity at 47°F39,000 BTU/h
Capacity at 17°F31,800 BTU/h
Capacity at 5°F38,000 BTU/h
COP at 5°F2.0 = twice as efficient as a space heater1.80
ENERGY STAR cold climateYes
Heating output as it gets colder97% kept at 5°F

Every heat pump delivers less heat as the outdoor temperature drops. Certified output of its matchup with AUH2-36N1-CM3E at the standard test temperatures, in BTU/h:

Certified matchups1 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 unitSEER2EER2HSPF2Heat @5°FAHRI ref.
AUH2-36N1-CM3E · cold climate16.311.79.538,000213769925
Yearly running cost in 10 large cities$1,008-$2,613

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

Questions5
What is the SEER2 rating of the AI AIR CONDITIONING AUO18-36N1-M3H?
The AI AIR CONDITIONING AUO18-36N1-M3H is rated at up to 16.3 SEER2 and 11.7 EER2 for cooling and up to 9.5 HSPF2 for heating. The exact figure depends on the indoor unit it is paired with.
Is the AI AIR CONDITIONING AUO18-36N1-M3H good for cold climates?
Yes. At least one certified matchup meets the ENERGY STAR cold-climate criteria, delivering up to 38,000 BTU/h at 5°F with a COP of 1.80, so it is still 1.8 times as efficient as electric resistance heat at that temperature.
How much does the AI AIR CONDITIONING AUO18-36N1-M3H cost to run per year?
At its rated efficiency it costs about $1,008-$2,613 a year in electricity in large U.S. cities, depending on climate and local rates - for example $1,231 in Phoenix and $2,175 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 AI AIR CONDITIONING AUO18-36N1-M3H?
ENERGY STAR lists 1 certified combination for this outdoor unit. The highest-rated one uses AUH2-36N1-CM3E.
What refrigerant does the AI AIR CONDITIONING AUO18-36N1-M3H use?
It uses R-410A. R-410A is being phased down under the EPA AIM Act, and new systems are moving to R-454B and R-32.

Running cost and savings

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

Heat pump $1,216/yrYou save $655/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 AI AIR CONDITIONING AUO18-36N1-M3H
3. What it replaces
4. Price replace the example with your quote
Heat pump, per year
$1,216
Current system, per year
$1,870
You save per year
$655
Payback
19.9 years
Net after 10 years
-$6,455

Cooling $756Heating $460Electricity used: 7,598 kWhSaved vs. a minimum-efficiency heat pump: $228

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.

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Source: ENERGY STAR Certified Heat Pumps (U.S. EPA), certification of June 9, 2026. How we use the data.