ACiQ Extreme Heat 18,000 BTU
#3 in 18,000 BTUFull review
ACiQ’s cold-climate line, sold online, keeps most of its rated heat at 5 °F, heats to −22 °F and gets a 12-year compressor warranty once registered. A certified technician has to install it.
The ACiQ Extreme Heat 18,000 BTU is the better mini-split overall, rated 4.7 to 4.5. The ACiQ Extreme Heat 18,000 BTU leads on noise and cold weather. The Fujitsu Orion XLTH 18,000 BTU wins on efficiency.
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.
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 ACiQ Extreme Heat 18,000 BTU for noise (indoor unit from 19.5 dB(A) vs indoor unit from 30 dB(A)) and cold weather (keeps 100% of its heat at 5 °F, heats down to -22 °F vs keeps 118% of its heat at 5 °F, heats down to -15 °F).
- Choose the Fujitsu Orion XLTH 18,000 BTU for efficiency (12.5 HSPF2, 25.5 SEER2, COP 2.02 at 5 °F vs 11 HSPF2, 21.4 SEER2, COP 1.92 at 5 °F).
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 | ACiQ Extreme Heat 18,000 BTU | Fujitsu Orion XLTH 18,000 BTU |
|---|---|---|
| Overall rating | 4.7/5 | 4.5/5 |
| Cold weather 40% | 100 keeps 100% of its heat at 5 °F, heats down to -22 °F | 90 keeps 118% of its heat at 5 °F, heats down to -15 °F |
| Efficiency 30% | 72 11 HSPF2, 21.4 SEER2, COP 1.92 at 5 °F | 86 12.5 HSPF2, 25.5 SEER2, COP 2.02 at 5 °F |
| Warranty 20% | 100 12-year compressor, 7-year parts | 100 10-year compressor, 10-year parts |
| Noise 10% | 98 indoor unit from 19.5 dB(A) | 48 indoor unit from 30 dB(A) |
Specifications
| ACiQ Extreme Heat 18,000 BTU | Fujitsu Orion XLTH 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 | 18,000 Btu/h | 21,600 Btu/h |
| Heating at 17 °F (max) | 19,200 Btu/h | 27,200 Btu/h |
| Heating at 5 °F (max) | 18,000 Btu/h | 25,400 Btu/h |
| Heat kept at 5 °F | 100% | 118% |
| Efficiency (certified) | ||
| HSPF2 (Region IV) | 11 | 12.5 |
| SEER2 | 21.4 | 25.5 |
| EER2 | 12.5 | 14 |
| COP at 5 °F | 1.92 | 2.02 |
| ENERGY STAR | ENERGY STAR Cold Climate | ENERGY STAR Cold Climate |
| AHRI certificate | 216032336 | 215647921 |
| Operating range | ||
| Heats down to | -22 °F | -15 °F |
| Cooling range | -22 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 98.4 ft | up to 164 ft |
| Voltage | 230 V | 230 V |
| Refrigerant | R-454B | R-32 |
| Indoor unit | ACIQ-18W-HH-MD | ASUH18KZAS |
| Outdoor unit | ACIQ-18ZPL-HP230C | AOUH18KZAH1 |
| Build | ||
| Indoor noise | 19.5–49.5 dB(A) | 30–46 dB(A) |
| Outdoor noise | 59 dB(A) | 47 dB(A) |
| Wi-Fi | Optional module | Built in |
| Weight | indoor 27.3 lb / outdoor 99.9 lb | indoor 36 lb / outdoor 117 lb |
| Warranty | 12 yr compressor, 7 yr parts | 10 yr compressor, 10 yr parts |
| Warranty with DIY install | No, a licensed installer is required | No, a licensed installer is required |