The Mini-Split

The Saga

three picks, two funerals

Three picks, two funerals. The first was the Mitsubishi MSZ-FS09NA — hyper-heat, CN105-moddable, and anchored to a $775 clearance condenser that turned out to be too good to be true: the matching indoor head was discontinued everywhere, the cheap condenser an orphan. Lesson banked — stock-check clearance before it becomes the plan. The pivot was the FX09, and the FX09 survived its stock check and died at the checkout: $2,652 is flagship money for a 169-sqft office with a working gas furnace already standing behind it. That's when the search stopped chasing a badge and started chasing the field — a July 18 sweep of Mr Cool, TOSOT, Senville, Pioneer, Della, Klimaire, and Fujitsu — and found something better than a consolation prize.

The Pick

the office · 120V · decided, third time honest

A unit at a fifth of the FX09's price with a cleaner local-control story than the CN105 solder mod: built-in WiFi that Home Assistant's native Gree integration drives over local UDP, documented in TOSOT's own Home Assistant guide. One cloud touch to bind WiFi at setup, then LAN-only forever. No dongle, no soldering, no Kumo.

Why 9k, not 6 or 12: the room math hasn't moved — 169 sqft with spillover duty, 6k leaves no margin, 12k short-cycles, a modulating 9k covers both the leaky era and the post-insulation one.

Why 120V

voltage ≠ efficiency

The voltage rationale has moved: 240V was only ever where Mitsubishi's hyper-heat catalog lived. Nothing about 120V costs this unit efficiency or capacity — SEER2/HSPF2 numbers above are for the 120V model as sold.

At 120V this unit wants a dedicated 20A circuit on 12 AWG (MCA 19A, MOP 20A; power lands at the condenser, the head feeds off the interconnect) — and in an outage it runs from any portable inverter generator's household outlet, no 240V inlet required (see Resilience).

The Install Runbook

flare-and-vacuum, not quick-connect — the honest shape

Standard flare-and-vacuum, not quick-connect — and that's fine. The lineset ships pre-flared with the charge waiting in the condenser, so the stock install is a short, ordered list, not a mystery:

1. Lineset ships pre-flared, charge already waiting in the condenser — no brazing.
2. Mount the plate into studs; drill the wall hole 2.2–2.8", sloped slightly downward so condensate runs outside, not into the stud bay.
3. Hang the head, connect the pre-flared lineset — torque the flare nuts to the manual's table: 12–14 ft-lb on the ¼" liquid line, 23–29 ft-lb on the ⅜" gas line.
4. Pull vacuum at the gas-valve service port. The manual's own bar is loose (−0.1 MPa for 10–15 min) — do it right anyway: micron gauge to 500 microns, and a cheap nitrogen pressure test first.
5. Hold-test the vacuum before touching anything else.
6. Open both valve cores with a hex key to release the factory charge into the lines.
7. Bubble-test every joint.
8. Drain the pump, wrap the lineset, commission the system.

Flaring only enters the job if a run gets shortened or a flare gets damaged. Max lineset run is 65 ft; there's no published charge-per-foot table, so the honest answer is stay near the 16 ft that ships in the box.

The Shopping List

what the box doesn't hold — bought at the orange store, ~$370–405

○ open To buy: the condenser landed Jul 23 — freight box dinged, unit fine — and the head unit followed Jul 24. Everything below is the not-in-box layer for the west-wall run: panel exit and exterior conduit down to the condenser's wall bracket, the breaker and disconnect, the mount, the hole through the brick, and the fine stuff a flare-and-vacuum job needs to finish right.

stock checked jul 24 2026 · home depot independence #3006 · 4210 s lees summit rd

Freight clock: photograph the dinged condenser box + unit now — freight claims want it within 5 days. Register within 30 days for the +6 months warranty.

The Run — panel exit + ~20 ft exterior conduit (≈$110)

The Power — breaker, disconnect, whip (≈$45; +$37 GFCI ordered, +$65 combo today)

The Mount — condenser on the wall (≈$65–105, bracket lane dependent)

ALT: Diversitech EL1838-3 ground pad $35 + risers ~$20 if bracket-height brick is ever questionable.

The Hole & Seal (≈$130 with the core kit)

The Fine Stuff (≈$35)

Run ~$110 + Power ~$50–108 (breaker, disconnect, whip, GFCI call) + Mount ~$62–102 (bracket call) + Hole & Seal ~$130 (incl. the two-hole core kit) + Fine stuff ~$35 ≈ $385–505 depending on the bracket and GFCI calls. With the unit ($595) and the refrigeration tool kit already listed (~$300), the whole project lands ≈ $1.35k all-in.

The lanes: IN STORE TODAY — everything in the run/power tables + anchors, caulk, tape, Wagos, and the Everbilt bracket.
HD ONLINE ship-to-store — DuctlessAire bracket $35, plain GFCI breaker.
AMAZON — BEWAVE lineset cover kit, TAUROX wall sleeve, Nylog Blue RT201B, Pangda cork tape.

• Freight clock: photograph the dinged condenser box + unit now (≤5 days for freight claims); register within 30 days for the +6 months warranty.
• Leave a service loop of lineset and interconnect at the head — brick and frame move.
• Re-torque the flares after the vacuum hold test, not just once.

Tools & Materials

~$250 in tools, once — then it's yours for the next one

Tools: ~$250 (reusable for the next job). Prices are street — check before buying.

Disconnect, whip, cover, and the rest of the materials layer moved to The Shopping List above.

Fine Print

the parts that aren't the pick, but matter

• R32, mildly flammable (A2L): no open flame near the work; the 9k unit's factory charge sits under every room-size threshold that would otherwise trigger extra ventilation rules.
• Freight, not the unit: the known weak spot is the pallet, not the hardware — photograph it on arrival and report any damage within 5 days.
• Register within 30 days for the extra 6 months of warranty coverage — a form, not a phone call.
• TOSOT Direct, the retailer: reviews of the storefront itself are mixed; the hardware underneath is Gree's, and that's fine. Judge the machine on its own.