The Della Optima Pro CloudAir 9,000 BTU 230V is the better DIY mini-split overall, rated 4.5 to 3.8. The Della Optima Pro CloudAir 9,000 BTU 230V leads on cold weather, value and efficiency. The Della Optima Pro CloudAir 9,000 BTU 230V costs $49.04 less ($1,049.96 vs $1,099).
The best value for heating through a cold winter, if you can pull a vacuum yourself or pay someone to. It holds its full rated heat at 5 °F for far less than a quick-connect unit that does the same.
Amazon $1,049.96 Della $1,049.96The 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 $1,099Prices 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.
Each factor is scored 0-100 against the same fixed reference points for every 9,000 BTU DIY mini-split; a clear win is highlighted. How we rank explains each one.
| Factor weight | Della Optima Pro CloudAir 9,000 BTU 230V | Klimaire KIWQ-KOIQ DIY 5th Gen 9,000 BTU 115V |
|---|---|---|
| Overall rating | 4.5/5 | 3.8/5 |
| Value 35% | 94 $115 per 1,000 Btu/h of heat at 5 °F | 81 $147 per 1,000 Btu/h of heat at 5 °F |
| Cold weather 25% | 100 keeps 101% of its heat at 5 °F, heats down to -22 °F | 57 keeps 75% of its heat at 5 °F, heats down to -13 °F |
| Efficiency 20% | 70 10.5 HSPF2, 25 SEER2, COP 1.80 at 5 °F | 51 9.5 HSPF2, 23 SEER2, COP 1.89 at 5 °F |
| Warranty 15% | 70 lifetime parts once registered, no compressor term stated | 64 7-year compressor, 5-year parts |
| Noise 5% | 67 indoor unit from 26 dB(A) | 48 indoor unit from 30 dB(A) |
| Della Optima Pro CloudAir 9,000 BTU 230V | Klimaire KIWQ-KOIQ DIY 5th Gen 9,000 BTU 115V | |
|---|---|---|
| Capacity (certified) | ||
| Size (nominal) | 9,000 BTU | 9,000 BTU |
| Cooling at 95 °F | 9,000 Btu/h | 9,000 Btu/h |
| Heating at 47 °F | 9,000 Btu/h | 10,000 Btu/h |
| Heating at 17 °F (max) | 10,000 Btu/h | 9,100 Btu/h |
| Heating at 5 °F (max) | 9,100 Btu/h | 7,500 Btu/h |
| Heat kept at 5 °F | 101% | 75% |
| Price per 1,000 Btu/h at 5 °F | $115 | $147 |
| Efficiency (certified) | ||
| HSPF2 (Region IV) | 10.5 | 9.5 |
| SEER2 | 25 | 23 |
| EER2 | 14.5 | 13 |
| COP at 5 °F | 1.80 | 1.89 |
| ENERGY STAR | ENERGY STAR Cold Climate | ENERGY STAR Cold Climate |
| AHRI certificate | 218471006 | 218067067 |
| Operating range | ||
| Heats down to | -22 °F | -13 °F |
| Cooling range | 5 to 131 °F | 5 to 131 °F |
| Installation | ||
| Line set connection | Flare fittings (vacuum pump needed) | Quick-connect (no vacuum pump) |
| Line set | 16.4 ft included, up to 49 ft | 25 ft included, up to 49 ft |
| Voltage | 230 V | 115 V |
| Refrigerant | R-454B | R-454B |
| Indoor unit | 048-TPH-9K2V-C-IN | KIWQ09H1-45T |
| Outdoor unit | 048-TPH-9K2V-25S-OUT | KOIQ09H1-45T |
| Build | ||
| Indoor noise | 26–42 dB(A) | 30–43 dB(A) |
| Outdoor noise | 55 dB(A) | 50 dB(A) |
| Wi-Fi | Built in | Built in |
| Room size (maker) | up to 400 sq ft | - |
| Weight | indoor 20.7 lb / outdoor 54 lb | indoor 20.7 lb / outdoor 53.5 lb |
| Warranty | lifetime parts (registered) | 7 yr compressor, 5 yr parts |
| Warranty with DIY install | Yes | Yes |
| Released | 2026-05 | 2025-10 |
