Our take in 30 seconds
Best for: cold and very cold climatesStrengths
- Keeps 87% 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
- Also sold under 9 other badges, so you can compare more quotes for the same unit
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 Day & Night D5CUHAH18AAK+KSAIC0701230 at the three ENERGY STAR test temperatures (cooling capacity is 18,700 BTU/h for reference).
Retention at 17°F: 76% · at 5°F: 87%. Learn how to use these numbers in our cold-climate guide.
Estimated running cost in every state
Same unit, very different bills: from about $519 a year in Louisiana to $2,032 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¢ | $202 | $317 | $519 |
| Florida | 14.99¢ | $151 | $443 | $594 |
| Mississippi | 14.43¢ | $291 | $320 | $611 |
| Washington | 14.63¢ | $558 | $63 | $621 |
| Nevada | 12.72¢ | $343 | $282 | $624 |
| Tennessee | 13.42¢ | $422 | $215 | $636 |
| Arizona | 15.05¢ | $236 | $407 | $644 |
| Oregon | 15.92¢ | $572 | $88 | $660 |
| North Carolina | 14.95¢ | $436 | $239 | $675 |
| Kentucky | 13.80¢ | $496 | $187 | $682 |
| Arkansas | 14.37¢ | $419 | $265 | $684 |
| South Carolina | 15.76¢ | $389 | $310 | $699 |
| Georgia | 15.90¢ | $393 | $313 | $706 |
| Texas | 15.91¢ | $321 | $391 | $713 |
| Utah | 13.31¢ | $568 | $147 | $715 |
| Alabama | 16.33¢ | $403 | $321 | $725 |
| Oklahoma | 14.82¢ | $466 | $273 | $739 |
| Idaho | 13.37¢ | $630 | $115 | $745 |
| New Mexico | 16.51¢ | $556 | $203 | $759 |
| Nebraska | 13.54¢ | $638 | $150 | $788 |
| West Virginia | 16.31¢ | $659 | $161 | $819 |
| Missouri | 16.02¢ | $611 | $217 | $828 |
| Virginia | 17.64¢ | $594 | $239 | $833 |
| Kansas | 15.47¢ | $625 | $209 | $834 |
| Wyoming | 14.43¢ | $810 | $89 | $898 |
| Colorado | 17.17¢ | $771 | $148 | $919 |
| North Dakota | 13.31¢ | $866 | $74 | $940 |
| Indiana | 17.02¢ | $764 | $178 | $942 |
| Delaware | 18.70¢ | $714 | $230 | $944 |
| Montana | 15.57¢ | $874 | $86 | $960 |
| California | 29.75¢ | $601 | $366 | $967 |
| South Dakota | 15.15¢ | $850 | $121 | $971 |
| Iowa | 17.06¢ | $881 | $157 | $1,038 |
| Ohio | 19.38¢ | $870 | $191 | $1,061 |
| Maryland | 21.40¢ | $817 | $263 | $1,080 |
| Illinois | 19.32¢ | $911 | $190 | $1,101 |
| Minnesota | 17.20¢ | $1,042 | $116 | $1,159 |
| Pennsylvania | 21.77¢ | $977 | $214 | $1,191 |
| Wisconsin | 19.41¢ | $1,089 | $143 | $1,232 |
| New Jersey | 24.61¢ | $994 | $272 | $1,267 |
| District of Columbia | 25.98¢ | $933 | $352 | $1,285 |
| Connecticut | 24.51¢ | $1,210 | $196 | $1,406 |
| Michigan | 22.99¢ | $1,238 | $170 | $1,408 |
| Vermont | 23.84¢ | $1,391 | $132 | $1,523 |
| Hawaii | 47.18¢ | $53 | $1,509 | $1,562 |
| Rhode Island | 28.18¢ | $1,391 | $208 | $1,599 |
| New York | 28.65¢ | $1,415 | $229 | $1,644 |
| New Hampshire | 27.64¢ | $1,551 | $170 | $1,721 |
| Massachusetts | 30.48¢ | $1,573 | $225 | $1,798 |
| Alaska | 29.41¢ | $1,980 | $36 | $2,016 |
| Maine | 32.11¢ | $1,874 | $158 | $2,032 |
Same equipment sold under other brands
These listings share the same certifying manufacturer (Carrier Corporation) and identical certified capacities and efficiency ratings, so they are almost certainly the same hardware with a different badge. If you get quotes for any of them, you are comparing installation price and warranty, not equipment. How rebadging works.
- Bryant 37MUHAQ18AA3+KSAIC0701230
- Carrier 37MUHAQ18AA3+KSAIC0701230
- Airquest D5CUHAH18AAK+KSAIC0701230
- Arcoaire D5CUHAH18AAK+KSAIC0701230
Plus 5 more identical listings in the ENERGY STAR database.
Similar-size alternatives
Other ducted split system units within ±15% of this model's cooling capacity, sorted by efficiency. Cost difference is versus the Day & Night D5CUHAH18AAK+KSAIC0701230 at U.S.-average rates.
| Model | Cooling BTU/h | SEER2 | HSPF2 | 5°F kept | Est. yearly cost | |
|---|---|---|---|---|---|---|
| Midea MO1HE-H18B-2A | 18,000 | 15.2–19.3 | 10.8 | 103% | $748 (−$150) | Compare |
| Rheem RD18AY24AJVC | 21,400 | 17–19 | 10 | 77% | $949 (+$51) | Compare |
| LG KUSXB181A | 18,000 | 15.2–17.5 | 10 | 110% | $818 (−$80) | Compare |
| Panasonic CU-HM18BAHU | 18,000 | 15.2–19 | 9.7 | 95% | $806 (−$92) | Compare |
| Daikin DH6VSA1810A* | 17,100 | 16–19 | 8.8 | 75% | $788 (−$110) | Compare |
| Lennox EL17XP1-018-230A** | 18,000 | 15.2–16.8 | 8.5 | 54% | $852 (−$46) | Compare |
Full specifications
| Brand | Day & Night |
| Outdoor model | D5CUHAH18AAK+KSAIC0701230 |
| Certified by | Carrier Corporation |
| Product type | Ducted split system |
| Compressor | Variable-speed (inverter) |
| Refrigerant | R-454B |
| Cooling capacity | 18,700 BTU/h |
| Nominal size | 1.5 tons |
| SEER2 (certified range) | 15.2 – 16.5 |
| EER2 (best) | 11 |
| HSPF2 (best) | 9 |
| Heating capacity @ 47°F | 20,200 BTU/h |
| Heating capacity @ 17°F | 15,300 BTU/h |
| Heating capacity @ 5°F | 17,600 BTU/h |
| COP @ 5°F | 2.04 |
| ENERGY STAR cold-climate | Yes |
| Certified indoor pairings | 63 |
| Latest certification | 2026-06 |
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 Day & Night D5CUHAH18AAK+KSAIC0701230 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 $898 per year ($652 heating, $246 cooling). It ranges from about $519 in Louisiana to $2,032 in Maine.
Does the Day & Night D5CUHAH18AAK+KSAIC0701230 work in cold weather?
Yes. It is ENERGY STAR cold-climate certified and delivers 17,600 BTU/h at 5°F, 87% of its 47°F capacity, with a COP of 2.04 at 5°F.
What size is the Day & Night D5CUHAH18AAK+KSAIC0701230?
It is rated at 18,700 BTU/h of cooling, roughly 1.5 tons, and 20,200 BTU/h of heating at 47°F. Proper sizing should be confirmed with a Manual J load calculation.
Is the Day & Night D5CUHAH18AAK+KSAIC0701230 the same as the Bryant 37MUHAQ18AA3+KSAIC0701230?
Very likely. Both are certified by Carrier Corporation with identical capacities and efficiency ratings in the ENERGY STAR database, which indicates the same equipment sold under different brands.