A cold-climate unit sold online by Senville that keeps most of its rated heat at 5 °F and heats to −22 °F. Parts cover is 5 years, half the compressor’s 10.
Senville $1,599.99
Mitsubishi’s mainstream Hyper-Heat line keeps its full rated heat at 5 °F and heats down to −13 °F. The FX goes further in deep cold and efficiency.
- 18,000 BTUSize
- 19,000 Btu/hHeat at 5 °F
- 100%Kept at 5 °F
- 10 / 22.5HSPF2 / SEER2
- Pro installInstall
No store we check sells it online; the maker lists where to buy or who installs it.
- Keeps 100% of its rated heat at 5 °F: 19,000 Btu/h
- 10-year parts and compressor warranty once registered
- Needs a licensed HVAC installer: a self-install voids the warranty
How it scores
The rating comes from 4 measured or published factors, each scored 0-100 against fixed reference points for its size. How we rank explains each one.
Specifications
| Capacity (certified) | |
|---|---|
| Size (nominal) | 18,000 BTU |
| Cooling at 95 °F | 18,000 Btu/h |
| Heating at 47 °F | 19,000 Btu/h |
| Heating at 17 °F (max) | 22,400 Btu/h |
| Heating at 5 °F (max) | 19,000 Btu/h |
| Heat kept at 5 °F | 100% |
| Efficiency (certified) | |
| HSPF2 (Region IV) | 10 |
| SEER2 | 22.5 |
| EER2 | 14.1 |
| COP at 5 °F | 1.80 |
| ENERGY STAR | ENERGY STAR Cold Climate |
| AHRI certificate | 215862740 |
| Operating range | |
| Heats down to | -13 °F |
| Cooling range | 14 to 115 °F |
| Installation | |
| Installed by | Professional (sold through installers) |
| Line set connection | Flare fittings (vacuum pump needed) |
| Line set | up to 100 ft |
| Voltage | 230 V |
| Refrigerant | R-454B |
| Indoor unit | MSZ-GX18NL |
| Outdoor unit | MUZ-GX18NLHZ |
| Build | |
| Indoor noise | 28–49 dB(A) |
| Outdoor noise | 54 dB(A) |
| Wi-Fi | Built in |
| Weight | indoor 37 lb / outdoor 117 lb |
| Warranty | 10 yr compressor, 10 yr parts |
| Warranty with DIY install | No, a licensed installer is required |
| Released | 2025-02 |
Alternatives in this size
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.
Amazon $3,173 MRCOOL DIY Direct $3,205Holds its full rated heat at 5 °F, heats to −13 °F and carries Daikin’s 12-year registered warranty, among the longest here.
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