Our take in 30 seconds
Best for: cold and very cold climatesStrengths
- Keeps 82% of its heat at 5°F, so backup heat rarely runs
- Heating efficiency (HSPF2 11.4) beats 94% of models
- Cooling efficiency up to SEER2 26.3, better than 97% of models
- Variable-speed compressor: quieter, steadier temperatures and better humidity control
Good to know
- Efficiency depends on the indoor unit: SEER2 ranges 18.6–26.3, so ask which pairing you're quoted
Running-cost calculator
Pre-filled with EIA prices · edit any fieldUses the base certified SEER2 (18.6) and HSPF2 (11.4). Assumes the unit is correctly sized. How we calculate.
Heating capacity as it gets colder
A heat pump's output falls as outdoor temperature drops. This is the certified heat output of the Fujitsu AOUH18KUAS1 at the three ENERGY STAR test temperatures (cooling capacity is 18,000 BTU/h for reference).
Retention at 17°F: 75% · at 5°F: 82%. Learn how to use these numbers in our cold-climate guide.
Estimated running cost in every state
Same unit, very different bills: from about $420 a year in Louisiana to $1,706 in Maine, driven by local electricity prices and how much heating or cooling the climate needs. Click a column to sort.
| State | Price | Heating | Cooling | Total / yr |
|---|---|---|---|---|
| Louisiana | 12.87¢ | $171 | $249 | $420 |
| Florida | 14.99¢ | $128 | $348 | $476 |
| Mississippi | 14.43¢ | $246 | $251 | $497 |
| Nevada | 12.72¢ | $289 | $222 | $511 |
| Arizona | 15.05¢ | $200 | $320 | $520 |
| Washington | 14.63¢ | $471 | $50 | $521 |
| Tennessee | 13.42¢ | $356 | $169 | $525 |
| Oregon | 15.92¢ | $483 | $69 | $552 |
| North Carolina | 14.95¢ | $368 | $188 | $556 |
| Arkansas | 14.37¢ | $354 | $209 | $563 |
| Kentucky | 13.80¢ | $418 | $147 | $565 |
| South Carolina | 15.76¢ | $328 | $244 | $572 |
| Georgia | 15.90¢ | $331 | $246 | $578 |
| Texas | 15.91¢ | $271 | $308 | $579 |
| Alabama | 16.33¢ | $340 | $253 | $593 |
| Utah | 13.31¢ | $479 | $116 | $595 |
| Oklahoma | 14.82¢ | $393 | $215 | $608 |
| Idaho | 13.37¢ | $532 | $91 | $623 |
| New Mexico | 16.51¢ | $469 | $160 | $629 |
| Nebraska | 13.54¢ | $539 | $118 | $657 |
| West Virginia | 16.31¢ | $556 | $126 | $683 |
| Missouri | 16.02¢ | $516 | $171 | $687 |
| Virginia | 17.64¢ | $501 | $188 | $689 |
| Kansas | 15.47¢ | $528 | $165 | $692 |
| Wyoming | 14.43¢ | $684 | $70 | $753 |
| Colorado | 17.17¢ | $651 | $116 | $767 |
| Delaware | 18.70¢ | $602 | $181 | $783 |
| Indiana | 17.02¢ | $645 | $140 | $785 |
| North Dakota | 13.31¢ | $731 | $58 | $789 |
| California | 29.75¢ | $507 | $288 | $795 |
| Montana | 15.57¢ | $738 | $68 | $805 |
| South Dakota | 15.15¢ | $718 | $95 | $813 |
| Iowa | 17.06¢ | $743 | $124 | $867 |
| Ohio | 19.38¢ | $734 | $150 | $884 |
| Maryland | 21.40¢ | $689 | $207 | $896 |
| Illinois | 19.32¢ | $769 | $150 | $918 |
| Minnesota | 17.20¢ | $880 | $92 | $971 |
| Pennsylvania | 21.77¢ | $825 | $169 | $994 |
| Wisconsin | 19.41¢ | $919 | $113 | $1,032 |
| New Jersey | 24.61¢ | $839 | $214 | $1,054 |
| District of Columbia | 25.98¢ | $788 | $277 | $1,064 |
| Connecticut | 24.51¢ | $1,022 | $154 | $1,176 |
| Michigan | 22.99¢ | $1,045 | $133 | $1,179 |
| Hawaii | 47.18¢ | $45 | $1,187 | $1,232 |
| Vermont | 23.84¢ | $1,174 | $104 | $1,278 |
| Rhode Island | 28.18¢ | $1,175 | $164 | $1,338 |
| New York | 28.65¢ | $1,194 | $180 | $1,374 |
| New Hampshire | 27.64¢ | $1,309 | $134 | $1,443 |
| Massachusetts | 30.48¢ | $1,328 | $177 | $1,505 |
| Alaska | 29.41¢ | $1,672 | $28 | $1,700 |
| Maine | 32.11¢ | $1,582 | $124 | $1,706 |
Similar-size alternatives
Other mini-split / multi-split units within ±15% of this model's cooling capacity, sorted by efficiency. Cost difference is versus the Fujitsu AOUH18KUAS1 at U.S.-average rates.
| Model | Cooling BTU/h | SEER2 | HSPF2 | 5°F kept | Est. yearly cost | |
|---|---|---|---|---|---|---|
| Bryant 37MARAQ18AA3 | 18,000 | 20–23.9 | 13.5 | 71% | $610 (−$134) | Compare |
| Bryant 37MAHAQ18AA3 | 18,000 | 18–21.5 | 12.4 | 90% | $668 (−$75) | Compare |
| Senville SENA-18HF-OG | 18,000 | 18–21.4 | 12.3 | 90% | $672 (−$72) | Compare |
| Fujitsu AOUH18LUAS1 | 18,000 | 18.6–23.5 | 11.2 | 95% | $660 (−$84) | Compare |
| Senville SENA/18HF/OQ | 18,000 | 18–21.5 | 11.3 | 95% | $688 (−$56) | Compare |
| Payne 38MARBQ18AA3 | 18,000 | 18–21.5 | 11.3 | 90% | $714 (−$30) | Compare |
Full specifications
| Brand | Fujitsu |
| Outdoor model | AOUH18KUAS1 |
| Certified by | Fujitsu General America, Inc. |
| Product type | Mini-split / multi-split |
| Compressor | Variable-speed (inverter) |
| Refrigerant | R-32 |
| Cooling capacity | 18,000 BTU/h |
| Nominal size | 1.5 tons |
| SEER2 (certified range) | 18.6 – 26.3 |
| EER2 (best) | 13.6 |
| HSPF2 (best) | 11.4 |
| Heating capacity @ 47°F | 21,600 BTU/h |
| Heating capacity @ 17°F | 16,100 BTU/h |
| Heating capacity @ 5°F | 17,800 BTU/h |
| COP @ 5°F | 2.4 |
| ENERGY STAR cold-climate | Yes |
| Certified indoor pairings | 6 |
| Latest certification | 2026-09 |
Source: ENERGY STAR Certified Heat Pumps (U.S. EPA), retrieved November 7, 2026. Capacities and HSPF2 are the highest values across certified pairings; confirm your exact system's AHRI reference number with your installer.
Frequently asked questions
How much does the Fujitsu AOUH18KUAS1 cost to run per year?
At the U.S. average residential electricity price of 18.16¢/kWh and typical national heating and cooling hours, we estimate about $744 per year ($551 heating, $193 cooling). It ranges from about $420 in Louisiana to $1,706 in Maine.
Does the Fujitsu AOUH18KUAS1 work in cold weather?
Yes. It is ENERGY STAR cold-climate certified and delivers 17,800 BTU/h at 5°F, 82% of its 47°F capacity, with a COP of 2.4 at 5°F.
What size is the Fujitsu AOUH18KUAS1?
It is rated at 18,000 BTU/h of cooling, roughly 1.5 tons, and 21,600 BTU/h of heating at 47°F. Proper sizing should be confirmed with a Manual J load calculation.