Our take in 30 seconds
Best for: mixed climates with occasional hard freezesStrengths
- Variable-speed compressor: quieter, steadier temperatures and better humidity control
- Also sold under 1 other badge, so you can compare more quotes for the same unit
Good to know
- Uses R-410A, a refrigerant being phased down; future service may cost more
Running-cost calculator
Pre-filled with EIA prices · edit any fieldUses the base certified SEER2 (17) and HSPF2 (8.6). 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 Daikin DZ6VSA421EA* at the three ENERGY STAR test temperatures (cooling capacity is 40,000 BTU/h for reference).
Retention at 17°F: 70% · at 5°F: 76%. Learn how to use these numbers in our cold-climate guide.
Estimated running cost in every state
Same unit, very different bills: from about $1,025 a year in Louisiana to $4,185 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¢ | $419 | $606 | $1,025 |
| Florida | 14.99¢ | $314 | $846 | $1,160 |
| Mississippi | 14.43¢ | $604 | $611 | $1,215 |
| Nevada | 12.72¢ | $710 | $539 | $1,249 |
| Arizona | 15.05¢ | $490 | $779 | $1,269 |
| Washington | 14.63¢ | $1,157 | $120 | $1,277 |
| Tennessee | 13.42¢ | $874 | $410 | $1,284 |
| Oregon | 15.92¢ | $1,185 | $169 | $1,353 |
| North Carolina | 14.95¢ | $904 | $457 | $1,361 |
| Arkansas | 14.37¢ | $869 | $507 | $1,376 |
| Kentucky | 13.80¢ | $1,027 | $357 | $1,384 |
| South Carolina | 15.76¢ | $806 | $593 | $1,400 |
| Georgia | 15.90¢ | $813 | $599 | $1,412 |
| Texas | 15.91¢ | $666 | $749 | $1,415 |
| Alabama | 16.33¢ | $835 | $615 | $1,450 |
| Utah | 13.31¢ | $1,176 | $282 | $1,458 |
| Oklahoma | 14.82¢ | $965 | $523 | $1,488 |
| Idaho | 13.37¢ | $1,306 | $220 | $1,526 |
| New Mexico | 16.51¢ | $1,152 | $388 | $1,540 |
| Nebraska | 13.54¢ | $1,323 | $287 | $1,609 |
| West Virginia | 16.31¢ | $1,365 | $307 | $1,673 |
| Missouri | 16.02¢ | $1,267 | $415 | $1,681 |
| Virginia | 17.64¢ | $1,231 | $457 | $1,687 |
| Kansas | 15.47¢ | $1,295 | $400 | $1,696 |
| Wyoming | 14.43¢ | $1,678 | $170 | $1,848 |
| Colorado | 17.17¢ | $1,597 | $283 | $1,880 |
| Delaware | 18.70¢ | $1,479 | $440 | $1,919 |
| Indiana | 17.02¢ | $1,583 | $340 | $1,924 |
| North Dakota | 13.31¢ | $1,795 | $141 | $1,936 |
| California | 29.75¢ | $1,245 | $700 | $1,945 |
| Montana | 15.57¢ | $1,810 | $165 | $1,975 |
| South Dakota | 15.15¢ | $1,762 | $232 | $1,993 |
| Iowa | 17.06¢ | $1,825 | $301 | $2,126 |
| Ohio | 19.38¢ | $1,803 | $365 | $2,168 |
| Maryland | 21.40¢ | $1,692 | $504 | $2,196 |
| Illinois | 19.32¢ | $1,887 | $364 | $2,251 |
| Minnesota | 17.20¢ | $2,160 | $223 | $2,383 |
| Pennsylvania | 21.77¢ | $2,025 | $410 | $2,435 |
| Wisconsin | 19.41¢ | $2,257 | $274 | $2,531 |
| New Jersey | 24.61¢ | $2,060 | $521 | $2,582 |
| District of Columbia | 25.98¢ | $1,933 | $672 | $2,606 |
| Connecticut | 24.51¢ | $2,508 | $375 | $2,883 |
| Michigan | 22.99¢ | $2,566 | $325 | $2,891 |
| Hawaii | 47.18¢ | $110 | $2,886 | $2,996 |
| Vermont | 23.84¢ | $2,883 | $252 | $3,135 |
| Rhode Island | 28.18¢ | $2,884 | $398 | $3,281 |
| New York | 28.65¢ | $2,932 | $438 | $3,370 |
| New Hampshire | 27.64¢ | $3,214 | $325 | $3,539 |
| Massachusetts | 30.48¢ | $3,261 | $430 | $3,691 |
| Alaska | 29.41¢ | $4,104 | $69 | $4,173 |
| Maine | 32.11¢ | $3,883 | $302 | $4,185 |
Same equipment sold under other brands
These listings share the same certifying manufacturer (Daikin Comfort Technologies Manufacturing, L.P.) 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.
- Amana ASZS60421EA*
Similar-size alternatives
Other ducted split system units within ±15% of this model's cooling capacity, sorted by efficiency. Cost difference is versus the Daikin DZ6VSA421EA* at U.S.-average rates.
| Model | Cooling BTU/h | SEER2 | HSPF2 | 5°F kept | Est. yearly cost | |
|---|---|---|---|---|---|---|
| Ruud UP19AY36AJVC | 34,200 | 19–21 | 10 | 87% | $1,353 (−$468) | Compare |
| Ruud UP19AY48AJVC | 45,500 | 18–19 | 10 | 92% | $1,827 (+$6) | Compare |
| Bryant 37MUHAQ36AA3 | 36,000 | 15.8–18 | 10.3 | 103% | $1,527 (−$294) | Compare |
| Daikin DH9VSA361CA* | 34,200 | 16.9–21 | 10 | 100% | $1,398 (−$424) | Compare |
| Panasonic CU-HM36BAHU | 36,000 | 15.6–17.4 | 10.3 | 103% | $1,533 (−$289) | Compare |
| MrCool CENTRAL-36-HP-C-230B00-O | 36,000 | 15.2–17.4 | 10.3 | 103% | $1,545 (−$276) | Compare |
Full specifications
| Brand | Daikin |
| Outdoor model | DZ6VSA421EA* |
| Certified by | Daikin Comfort Technologies Manufacturing, L.P. |
| Product type | Ducted split system |
| Compressor | Variable-speed (inverter) |
| Refrigerant | R-410A |
| Cooling capacity | 40,000 BTU/h |
| Nominal size | 3.5 tons |
| SEER2 (certified range) | 17 – 17 |
| EER2 (best) | 10 |
| HSPF2 (best) | 8.6 |
| Heating capacity @ 47°F | 40,000 BTU/h |
| Heating capacity @ 17°F | 28,000 BTU/h |
| Heating capacity @ 5°F | 30,600 BTU/h |
| COP @ 5°F | 2.2 |
| ENERGY STAR cold-climate | Yes |
| Certified indoor pairings | 20 |
| Latest certification | 2026-08 |
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 Daikin DZ6VSA421EA* 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 $1,821 per year ($1,351 heating, $470 cooling). It ranges from about $1,025 in Louisiana to $4,185 in Maine.
Does the Daikin DZ6VSA421EA* work in cold weather?
Yes. It is ENERGY STAR cold-climate certified and delivers 30,600 BTU/h at 5°F, 76% of its 47°F capacity, with a COP of 2.2 at 5°F.
What size is the Daikin DZ6VSA421EA*?
It is rated at 40,000 BTU/h of cooling, roughly 3.5 tons, and 40,000 BTU/h of heating at 47°F. Proper sizing should be confirmed with a Manual J load calculation.
Is the Daikin DZ6VSA421EA* the same as the Amana ASZS60421EA*?
Very likely. Both are certified by Daikin Comfort Technologies Manufacturing, L.P. with identical capacities and efficiency ratings in the ENERGY STAR database, which indicates the same equipment sold under different brands.