Our take in 30 seconds
Best for: cold and very cold climatesStrengths
- Keeps 90% of its heat at 5°F, so backup heat rarely runs
- Heating efficiency (HSPF2 12.3) beats 97% of models
- Cooling efficiency up to SEER2 21.4, better than 76% of models
- Variable-speed compressor: quieter, steadier temperatures and better humidity control
Good to know
- Efficiency depends on the indoor unit: SEER2 ranges 18–21.4, so ask which pairing you're quoted
Running-cost calculator
Pre-filled with EIA prices · edit any fieldUses the base certified SEER2 (18) and HSPF2 (12.3). 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 Senville SENA-18HF-OG at the three ENERGY STAR test temperatures (cooling capacity is 18,000 BTU/h for reference).
Retention at 17°F: 90% · at 5°F: 90%. Learn how to use these numbers in our cold-climate guide.
Estimated running cost in every state
Same unit, very different bills: from about $404 a year in Louisiana to $1,486 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¢ | $146 | $257 | $404 |
| Washington | 14.63¢ | $404 | $51 | $456 |
| Florida | 14.99¢ | $110 | $360 | $469 |
| Mississippi | 14.43¢ | $211 | $260 | $471 |
| Nevada | 12.72¢ | $248 | $229 | $477 |
| Tennessee | 13.42¢ | $305 | $174 | $480 |
| Oregon | 15.92¢ | $414 | $72 | $486 |
| Arizona | 15.05¢ | $171 | $331 | $502 |
| North Carolina | 14.95¢ | $316 | $194 | $510 |
| Kentucky | 13.80¢ | $359 | $152 | $511 |
| Arkansas | 14.37¢ | $304 | $216 | $519 |
| Utah | 13.31¢ | $411 | $120 | $531 |
| South Carolina | 15.76¢ | $282 | $252 | $534 |
| Georgia | 15.90¢ | $284 | $254 | $539 |
| Idaho | 13.37¢ | $457 | $94 | $550 |
| Texas | 15.91¢ | $233 | $318 | $551 |
| Alabama | 16.33¢ | $292 | $261 | $553 |
| Oklahoma | 14.82¢ | $337 | $222 | $560 |
| New Mexico | 16.51¢ | $403 | $165 | $568 |
| Nebraska | 13.54¢ | $462 | $122 | $584 |
| West Virginia | 16.31¢ | $477 | $130 | $608 |
| Missouri | 16.02¢ | $443 | $176 | $619 |
| Kansas | 15.47¢ | $453 | $170 | $623 |
| Virginia | 17.64¢ | $430 | $194 | $624 |
| Wyoming | 14.43¢ | $587 | $72 | $659 |
| Colorado | 17.17¢ | $558 | $120 | $679 |
| North Dakota | 13.31¢ | $628 | $60 | $688 |
| Indiana | 17.02¢ | $553 | $145 | $698 |
| Montana | 15.57¢ | $633 | $70 | $703 |
| Delaware | 18.70¢ | $517 | $187 | $704 |
| South Dakota | 15.15¢ | $616 | $98 | $714 |
| California | 29.75¢ | $435 | $298 | $733 |
| Iowa | 17.06¢ | $638 | $128 | $766 |
| Ohio | 19.38¢ | $630 | $155 | $785 |
| Maryland | 21.40¢ | $592 | $214 | $806 |
| Illinois | 19.32¢ | $660 | $155 | $814 |
| Minnesota | 17.20¢ | $755 | $95 | $850 |
| Pennsylvania | 21.77¢ | $708 | $174 | $882 |
| Wisconsin | 19.41¢ | $789 | $116 | $905 |
| New Jersey | 24.61¢ | $720 | $221 | $942 |
| District of Columbia | 25.98¢ | $676 | $286 | $962 |
| Michigan | 22.99¢ | $897 | $138 | $1,035 |
| Connecticut | 24.51¢ | $877 | $159 | $1,036 |
| Vermont | 23.84¢ | $1,008 | $107 | $1,115 |
| Rhode Island | 28.18¢ | $1,008 | $169 | $1,177 |
| New York | 28.65¢ | $1,025 | $186 | $1,211 |
| New Hampshire | 27.64¢ | $1,124 | $138 | $1,262 |
| Hawaii | 47.18¢ | $38 | $1,227 | $1,265 |
| Massachusetts | 30.48¢ | $1,140 | $183 | $1,323 |
| Alaska | 29.41¢ | $1,435 | $29 | $1,464 |
| Maine | 32.11¢ | $1,357 | $128 | $1,486 |
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 Senville SENA-18HF-OG 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 (−$62) | Compare |
| Bryant 37MAHAQ18AA3 | 18,000 | 18–21.5 | 12.4 | 90% | $668 (−$4) | Compare |
| Fujitsu AOUH18KUAS1 | 18,000 | 18.6–26.3 | 11.4 | 82% | $744 (+$72) | Compare |
| Fujitsu AOUH18LUAS1 | 18,000 | 18.6–23.5 | 11.2 | 95% | $660 (−$12) | Compare |
| Senville SENA/18HF/OQ | 18,000 | 18–21.5 | 11.3 | 95% | $688 (+$16) | Compare |
| Payne 38MARBQ18AA3 | 18,000 | 18–21.5 | 11.3 | 90% | $714 (+$42) | Compare |
Full specifications
| Brand | Senville |
| Outdoor model | SENA-18HF-OG |
| Certified by | Senville Air Conditioners |
| Product type | Mini-split / multi-split |
| Compressor | Variable-speed (inverter) |
| Refrigerant | R-454B |
| Cooling capacity | 18,000 BTU/h |
| Nominal size | 1.5 tons |
| SEER2 (certified range) | 18 – 21.4 |
| EER2 (best) | 12.5 |
| HSPF2 (best) | 12.3 |
| Heating capacity @ 47°F | 20,000 BTU/h |
| Heating capacity @ 17°F | 18,000 BTU/h |
| Heating capacity @ 5°F | 18,000 BTU/h |
| COP @ 5°F | 2 |
| ENERGY STAR cold-climate | Yes |
| Certified indoor pairings | 5 |
| Latest certification | 2026-05 |
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 Senville SENA-18HF-OG 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 $672 per year ($472 heating, $200 cooling). It ranges from about $404 in Louisiana to $1,486 in Maine.
Does the Senville SENA-18HF-OG work in cold weather?
Yes. It is ENERGY STAR cold-climate certified and delivers 18,000 BTU/h at 5°F, 90% of its 47°F capacity, with a COP of 2 at 5°F.
What size is the Senville SENA-18HF-OG?
It is rated at 18,000 BTU/h of cooling, roughly 1.5 tons, and 20,000 BTU/h of heating at 47°F. Proper sizing should be confirmed with a Manual J load calculation.