The Della Optima CloudAir 9,000 BTU 115V is the better DIY mini-split overall, rated 3.9 to 3.6. The Della Optima CloudAir 9,000 BTU 115V leads on value. The Della Optima CloudAir 9,000 BTU 115V costs $158.04 less ($899.96 vs $1,058).
The cheapest way into a certified, cold-capable heat pump, for a self-installer with a vacuum pump. Pioneer’s Quantum Ultra and the quick-connect Klimaire DIY have near-identical certified ratings.
Amazon $899.96 Della $899.96A low price for a self-installer who owns or will rent a vacuum pump. The Klimaire DIY is the same certified system with quick-connect lines, and Della’s Optima has near-identical ratings for less.
Amazon $1,058 Pioneer Mini Split store $1,058Prices 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 CloudAir 9,000 BTU 115V | Pioneer Quantum Ultra 9,000 BTU 230V |
|---|---|---|
| Overall rating | 3.9/5 | 3.6/5 |
| Value 35% | 89 $127 per 1,000 Btu/h of heat at 5 °F | 80 $149 per 1,000 Btu/h of heat at 5 °F |
| Cold weather 25% | 52 keeps 71% of its heat at 5 °F, heats down to -13 °F | 52 keeps 71% of its heat at 5 °F, heats down to -13 °F |
| Efficiency 20% | 51 9.5 HSPF2, 23 SEER2, COP 1.90 at 5 °F | 49 9.5 HSPF2, 23 SEER2, COP 1.84 at 5 °F |
| Warranty 15% | 70 lifetime parts once registered, no compressor term stated | 49 5-year compressor, 5-year parts, for a DIY install |
| Noise 5% | 48 indoor unit from 30 dB(A) | 48 indoor unit from 30 dB(A) |
| Della Optima CloudAir 9,000 BTU 115V | Pioneer Quantum Ultra 9,000 BTU 230V | |
|---|---|---|
| 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 | 10,000 Btu/h | 10,000 Btu/h |
| Heating at 17 °F (max) | 8,000 Btu/h | 9,100 Btu/h |
| Heating at 5 °F (max) | 7,100 Btu/h | 7,100 Btu/h |
| Heat kept at 5 °F | 71% | 71% |
| Price per 1,000 Btu/h at 5 °F | $127 | $149 |
| Efficiency (certified) | ||
| HSPF2 (Region IV) | 9.5 | 9.5 |
| SEER2 | 23 | 23 |
| EER2 | 13 | 13 |
| COP at 5 °F | 1.90 | 1.84 |
| ENERGY STAR | ENERGY STAR Cold Climate | ENERGY STAR Cold Climate |
| AHRI certificate | 218718733 | 217048749 |
| Operating range | ||
| Heats down to | -13 °F | -13 °F |
| Cooling range | 5 to 131 °F | 5 to 131 °F |
| Installation | ||
| Line set connection | Flare fittings (vacuum pump needed) | Flare fittings (vacuum pump needed) |
| Line set | 16.4 ft included, up to 49 ft | 16 ft included, up to 50 ft |
| Voltage | 115 V | 230 V |
| Refrigerant | R-454B | R-454B |
| Indoor unit | 048-TP-9K1V-C-IN | WT009GLSI24HLG |
| Outdoor unit | 048-TP-9K1V-24S-OUT | YN009GLSI24RPG |
| Build | ||
| Indoor noise | 30–43 dB(A) | 30–43 dB(A) |
| Outdoor noise | 50 dB(A) | 50 dB(A) |
| Wi-Fi | Built in | Built in |
| Room size (maker) | up to 400 sq ft | up to 350 sq ft |
| Weight | indoor 20.7 lb / outdoor 58.4 lb | indoor 20.7 lb / outdoor 52.7 lb |
| Warranty | lifetime parts (registered) | 10 yr compressor, 7 yr parts |
| Warranty with DIY install | Yes | Yes |
| DIY install warranty | - | 5 yr compressor, 5 yr parts |
| Released | 2026-06 | 2025-06 |
