Best Mini Split for a ADU / In-Law Suite
A detached ADU or in-law suite is a small apartment's worth of load: 18k single-zone for open plans, or a 2-zone when the bedroom closes off. The systems below include both shapes. Our dataset holds 10 verified system(s) here, 10 with first-hand prices from $999.99 to $4,214.25; the cheapest is the Senville LETO 18k, and 2 of them are true DIY (pre-charged line sets).
Computed from our dataset
- 10 system(s) from our verified dataset appear on this page.
- Price range: $999.99 to $4,214.25 (verified 2026-11-04).
- Cheapest: Senville LETO 18k at $999.99 (Senville).
- Highest SEER2: MRCOOL DIY 5th Gen 2-Zone 18k (6+6) at 23.9 SEER2.
- Best heating rating: MRCOOL DIY 5th Gen 18k, rated to -13°F.
- True DIY in this list: 2 system(s) with factory pre-charged line sets.
| System | Zones | BTU | Coverage | SEER2 | Heats to | Install | Price | |
|---|---|---|---|---|---|---|---|---|
| Senville LETO 18k SENL-18CD | 1 | 18,000 | 700-1,000 sq ft | 19.2 | 5°F | Pro / flare | $999.99 at Senville | Check price |
| Pioneer Diamante Pro 18k WYT018GLSI20RL | 1 | 18,000 | 500-750 sq ft | 21 | -4°F | Pro / flare | $1,178$1,679 at Pioneer Mini Split | Check price |
| MRCOOL DIY Easy Pro 18k EZPRO-18-HP-23016D-O | 1 | 18,000 | up to 800 sq ft | 20 | -13°F | True DIY | $1,827 at HVACDirect | Check price at HVACDirect |
| Pioneer Quantum Ultra 18k Dual-Zone (2x 9k) Quantum Ultra YN020GLFI20M2D | 2 | 18,000 | — | — | -13°F | Pro / flare | $2,094 at Pioneer Mini Split | Check price |
| MRCOOL DIY 5th Gen 2-Zone 18k (6+6) DIY-MULTI3-18HP230 | 2 | 18,000 | — | 23.9 | -13°F | Pro / flare | $2,469$2,715.90 at HVACDirect | Check price at HVACDirect |
| MRCOOL DIY 5th Gen 18k DIY-18-HP-WM-230D25-O | 1 | 18,000 | up to 800 sq ft | 21.5 | -13°F | True DIY | $2,909 at HVACDirect | Check price at HVACDirect |
| Daikin Aurora 18k FTXV18AVJU9 / RXT18AVJU9 | 1 | 18,000 | — | 21 | -13°F | Pro / flare | $3,932 at Alpine Home Air | Check price |
| Daikin Aurora MXT 18k 2-Zone (7+15) 2MXT18AVJU9 | 2 | 18,000 | — | 21 | — | Pro / flare | $3,956 at HVACDirect | Check price at HVACDirect |
| LG Multi F RED 18k 2-Zone (12+9) KUMXA181A | 2 | 18,000 | 900-1,050 sq ft | 20 | — | Pro / flare | $4,076 at HVACDirect | Check price at HVACDirect |
| Mitsubishi EX-Series Hyper-Heat 18k SUZ-AA18NLHZ / MSZ-EX18NLS | 1 | 18,000 | up to ~800 sq ft | 17.5 | -13°F | Pro / flare | $4,214.25 at HVACDirect | Check price at HVACDirect |
Buying notes
- Match the system to the space's worst season: cooling load sets the class, the heating rating decides whether it is a year-round tool.
- Every system here is a verified, priced single-zone (or, for ADUs, a small multi-zone) - class pages list the full field including unpriced systems.