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
- Variable-speed compressor: quieter, steadier temperatures and better humidity control
- Uses newer, lower-impact R-454B refrigerant
Good to know
- No notable drawbacks in the certified data.
Running-cost calculator
Pre-filled with EIA prices · edit any fieldUses the base certified SEER2 (15.2) and HSPF2 (9). 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 Panasonic CU-HM55BAHU at the three ENERGY STAR test temperatures (cooling capacity is 54,000 BTU/h for reference).
Retention at 17°F: 78% · 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 $1,495 a year in Louisiana to $5,837 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¢ | $581 | $914 | $1,495 |
| Florida | 14.99¢ | $435 | $1,278 | $1,713 |
| Mississippi | 14.43¢ | $837 | $923 | $1,760 |
| Washington | 14.63¢ | $1,603 | $182 | $1,785 |
| Nevada | 12.72¢ | $984 | $813 | $1,797 |
| Tennessee | 13.42¢ | $1,211 | $620 | $1,831 |
| Arizona | 15.05¢ | $679 | $1,176 | $1,855 |
| Oregon | 15.92¢ | $1,642 | $255 | $1,896 |
| North Carolina | 14.95¢ | $1,252 | $690 | $1,943 |
| Kentucky | 13.80¢ | $1,423 | $539 | $1,962 |
| Arkansas | 14.37¢ | $1,204 | $766 | $1,970 |
| South Carolina | 15.76¢ | $1,117 | $896 | $2,013 |
| Georgia | 15.90¢ | $1,127 | $904 | $2,031 |
| Texas | 15.91¢ | $923 | $1,130 | $2,053 |
| Utah | 13.31¢ | $1,630 | $426 | $2,055 |
| Alabama | 16.33¢ | $1,158 | $928 | $2,086 |
| Oklahoma | 14.82¢ | $1,337 | $790 | $2,127 |
| Idaho | 13.37¢ | $1,809 | $332 | $2,142 |
| New Mexico | 16.51¢ | $1,596 | $587 | $2,183 |
| Nebraska | 13.54¢ | $1,832 | $433 | $2,265 |
| West Virginia | 16.31¢ | $1,892 | $464 | $2,356 |
| Missouri | 16.02¢ | $1,755 | $626 | $2,381 |
| Virginia | 17.64¢ | $1,705 | $689 | $2,395 |
| Kansas | 15.47¢ | $1,795 | $605 | $2,399 |
| Wyoming | 14.43¢ | $2,325 | $256 | $2,581 |
| Colorado | 17.17¢ | $2,213 | $427 | $2,640 |
| North Dakota | 13.31¢ | $2,487 | $213 | $2,700 |
| Indiana | 17.02¢ | $2,194 | $514 | $2,708 |
| Delaware | 18.70¢ | $2,049 | $664 | $2,713 |
| Montana | 15.57¢ | $2,508 | $249 | $2,757 |
| California | 29.75¢ | $1,726 | $1,057 | $2,782 |
| South Dakota | 15.15¢ | $2,441 | $350 | $2,791 |
| Iowa | 17.06¢ | $2,529 | $455 | $2,983 |
| Ohio | 19.38¢ | $2,498 | $551 | $3,049 |
| Maryland | 21.40¢ | $2,344 | $760 | $3,105 |
| Illinois | 19.32¢ | $2,615 | $549 | $3,164 |
| Minnesota | 17.20¢ | $2,993 | $336 | $3,329 |
| Pennsylvania | 21.77¢ | $2,806 | $619 | $3,425 |
| Wisconsin | 19.41¢ | $3,127 | $414 | $3,541 |
| New Jersey | 24.61¢ | $2,855 | $787 | $3,642 |
| District of Columbia | 25.98¢ | $2,679 | $1,015 | $3,694 |
| Connecticut | 24.51¢ | $3,475 | $566 | $4,041 |
| Michigan | 22.99¢ | $3,556 | $490 | $4,046 |
| Vermont | 23.84¢ | $3,995 | $381 | $4,376 |
| Hawaii | 47.18¢ | $152 | $4,358 | $4,510 |
| Rhode Island | 28.18¢ | $3,995 | $601 | $4,596 |
| New York | 28.65¢ | $4,062 | $662 | $4,724 |
| New Hampshire | 27.64¢ | $4,453 | $491 | $4,944 |
| Massachusetts | 30.48¢ | $4,518 | $650 | $5,168 |
| Alaska | 29.41¢ | $5,686 | $104 | $5,790 |
| Maine | 32.11¢ | $5,380 | $456 | $5,837 |
Similar-size alternatives
Other ducted split system units within ±15% of this model's cooling capacity, sorted by efficiency. Cost difference is versus the Panasonic CU-HM55BAHU at U.S.-average rates.
| Model | Cooling BTU/h | SEER2 | HSPF2 | 5°F kept | Est. yearly cost | |
|---|---|---|---|---|---|---|
| Gree GUD60W2/NHE-D(U) | 53,000 | 16–19 | 10.5 | 100% | $2,156 (−$426) | Compare |
| Heil B5H3V48*K*AAA* | 46,500 | 20–23 | 9.5 | 76% | $1,963 (−$619) | Compare |
| Tempstar T5H3V48*K*AAA* | 46,500 | 19.5–23 | 9.5 | 72% | $2,113 (−$470) | Compare |
| Rheem RD18AY60AJVC | 52,000 | 16–18 | 10 | 66% | $2,393 (−$190) | Compare |
| Carrier 27VPA948A*030* | 49,500 | 15.2–19 | 10 | 75% | $2,249 (−$334) | Compare |
| Bosch BOVA-60MTB-M19E | 53,500 | 15.2–19 | 10 | 100% | $2,301 (−$281) | Compare |
Full specifications
| Brand | Panasonic |
| Outdoor model | CU-HM55BAHU |
| Certified by | Panasonic |
| Product type | Ducted split system |
| Compressor | Variable-speed (inverter) |
| Refrigerant | R-454B |
| Cooling capacity | 54,000 BTU/h |
| Nominal size | 4.5 tons |
| SEER2 (certified range) | 15.2 – 17.1 |
| EER2 (best) | 10.3 |
| HSPF2 (best) | 9 |
| Heating capacity @ 47°F | 58,000 BTU/h |
| Heating capacity @ 17°F | 45,000 BTU/h |
| Heating capacity @ 5°F | 52,000 BTU/h |
| COP @ 5°F | 1.83 |
| ENERGY STAR cold-climate | Yes |
| Certified indoor pairings | 8 |
| Latest certification | 2026-01 |
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 Panasonic CU-HM55BAHU 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 $2,582 per year ($1,872 heating, $710 cooling). It ranges from about $1,495 in Louisiana to $5,837 in Maine.
Does the Panasonic CU-HM55BAHU work in cold weather?
Yes. It is ENERGY STAR cold-climate certified and delivers 52,000 BTU/h at 5°F, 90% of its 47°F capacity, with a COP of 1.83 at 5°F.
What size is the Panasonic CU-HM55BAHU?
It is rated at 54,000 BTU/h of cooling, roughly 4.5 tons, and 58,000 BTU/h of heating at 47°F. Proper sizing should be confirmed with a Manual J load calculation.