Fujitsu Orion XLTH 18,000 BTU
#4 in 18,000 BTUFull review
Fujitsu’s cold-climate line, with more than its rated heat at 5 °F and very high certified efficiency, for homes heating through a cold winter.
The Fujitsu Orion XLTH 18,000 BTU is the better mini-split overall, rated 4.5 to 4.1. The Fujitsu Orion XLTH 18,000 BTU leads on cold weather and efficiency. The Fujitsu Altair 500 18,000 BTU wins on noise.
Fujitsu Altair 500 18,000 BTU
#10 in 18,000 BTUFull review
Fujitsu’s mainstream line for cooling and mild-winter heating, with a 10-year registered warranty. It stops heating below 5 °F.
Prices were last checked October 21, 2026 and are subject to change; the price and availability shown by the retailer at the time of purchase apply.
Which should you buy?
- Choose the Fujitsu Orion XLTH 18,000 BTU for cold weather (keeps 118% of its heat at 5 °F, heats down to -15 °F vs keeps 103% of its heat at 5 °F, heats down to 5 °F) and efficiency (12.5 HSPF2, 25.5 SEER2, COP 2.02 at 5 °F vs 10.5 HSPF2, 22 SEER2, COP 2.21 at 5 °F).
- Choose the Fujitsu Altair 500 18,000 BTU for noise (indoor unit from 26 dB(A) vs indoor unit from 30 dB(A)).
Scores side by side
Each factor is scored 0-100 against the same fixed reference points for every 18,000 BTU mini-split; a clear win is highlighted. How we rank explains each one.
| Factor weight | Fujitsu Orion XLTH 18,000 BTU | Fujitsu Altair 500 18,000 BTU |
|---|---|---|
| Overall rating | 4.5/5 | 4.1/5 |
| Cold weather 40% | 90 keeps 118% of its heat at 5 °F, heats down to -15 °F | 60 keeps 103% of its heat at 5 °F, heats down to 5 °F |
| Efficiency 30% | 86 12.5 HSPF2, 25.5 SEER2, COP 2.02 at 5 °F | 76 10.5 HSPF2, 22 SEER2, COP 2.21 at 5 °F |
| Warranty 20% | 100 10-year compressor, 10-year parts | 100 10-year compressor, 10-year parts |
| Noise 10% | 48 indoor unit from 30 dB(A) | 67 indoor unit from 26 dB(A) |
Specifications
| Fujitsu Orion XLTH 18,000 BTU | Fujitsu Altair 500 18,000 BTU | |
|---|---|---|
| Capacity (certified) | ||
| Size (nominal) | 18,000 BTU | 18,000 BTU |
| Cooling at 95 °F | 18,000 Btu/h | 18,000 Btu/h |
| Heating at 47 °F | 21,600 Btu/h | 18,000 Btu/h |
| Heating at 17 °F (max) | 27,200 Btu/h | 21,700 Btu/h |
| Heating at 5 °F (max) | 25,400 Btu/h | 18,500 Btu/h |
| Heat kept at 5 °F | 118% | 103% |
| Efficiency (certified) | ||
| HSPF2 (Region IV) | 12.5 | 10.5 |
| SEER2 | 25.5 | 22 |
| EER2 | 14 | 12.5 |
| COP at 5 °F | 2.02 | 2.21 |
| ENERGY STAR | ENERGY STAR Cold Climate | ENERGY STAR Cold Climate |
| AHRI certificate | 215647921 | 215441046 |
| Operating range | ||
| Heats down to | -15 °F | 5 °F |
| Cooling range | 14 to 122 °F | 14 to 122 °F |
| Installation | ||
| Installed by | Professional (sold through installers) | Professional (sold through installers) |
| Line set connection | Flare fittings (vacuum pump needed) | Flare fittings (vacuum pump needed) |
| Line set | up to 164 ft | up to 98 ft |
| Voltage | 230 V | 230 V |
| Refrigerant | R-32 | R-32 |
| Indoor unit | ASUH18KZAS | ASUH18KPAS |
| Outdoor unit | AOUH18KZAH1 | AOUH18KPAS1 |
| Build | ||
| Indoor noise | 30–46 dB(A) | 26–44 dB(A) |
| Outdoor noise | 47 dB(A) | 50 dB(A) |
| Wi-Fi | Built in | Optional module |
| Weight | indoor 36 lb / outdoor 117 lb | indoor 28 lb / outdoor 86 lb |
| Warranty | 10 yr compressor, 10 yr parts | 10 yr compressor, 10 yr parts |
| Warranty with DIY install | No, a licensed installer is required | No, a licensed installer is required |