For cold-climate homes where a quick-connect install matters more than price: it holds its full heat far colder than other quick-connect units. Flare-connect units match its cold-weather output for much less.
Price checked October 21, 2026. As an Amazon Associate we earn from qualifying purchases.
The rating comes from 5 measured or published factors, each scored 0-100 against fixed reference points for its size. How we rank explains each one.
| Capacity (certified) | |
|---|---|
| Size (nominal) | 12,000 BTU |
| Cooling at 95 °F | 12,000 Btu/h |
| Heating at 47 °F | 12,000 Btu/h |
| Heating at 17 °F (max) | 12,500 Btu/h |
| Heating at 5 °F (max) | 11,000 Btu/h |
| Heat kept at 5 °F | 92% |
| Price per 1,000 Btu/h at 5 °F | $230 |
| Efficiency (certified) | |
| HSPF2 (Region IV) | 10 |
| SEER2 | 23.5 |
| EER2 | 12.8 |
| COP at 5 °F | 1.80 |
| ENERGY STAR | ENERGY STAR Cold Climate |
| AHRI certificate | 216032549 |
| Operating range | |
| Heats down to | -22 °F |
| Cooling range | -22 to 122 °F |
| Installation | |
| Line set connection | Quick-connect (no vacuum pump) |
| Line set | 25 ft included, up to 75 ft |
| Voltage | 230 V |
| Refrigerant | R-454B |
| Indoor unit | DIY-12-HP-WMAH-230D25-O |
| Outdoor unit | DIYHH-12-HP-C-230D25-O |
| Build | |
| Indoor noise | 18–45.5 dB(A) |
| Outdoor noise | 56.5 dB(A) |
| Wi-Fi | Built in |
| Room size (maker) | up to 550 sq ft |
| Weight | indoor 24.5 lb / outdoor 72.3 lb |
| Warranty | 7 yr compressor, 5 yr parts |
| Warranty with DIY install | Yes |
The best-value quick-connect line: the same certified system as Pioneer’s Quantum Ultra, close to Della’s Optima, without the vacuum pump, for the same price or a few hundred dollars more.
Amazon $1,369The best-value quick-connect line: the same certified system as Pioneer’s Quantum Ultra, close to Della’s Optima, without the vacuum pump, for the same price or a few hundred dollars more.
Amazon $1,459For someone who wants a true plug-together install with no tools beyond a drill, and a warranty that survives it. Expect to pay well over the price of a flare unit with the same cold-weather output.
Amazon $1,759 MRCOOL DIY Direct $2,370Compare the MrCool DIY Hyper Heat 5th Gen 12,000 BTU 230V with any other DIY mini-split →
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