TOSOT Cosmo 9,000 BTU wall mount system
TOSOT Cosmo · Single-zone systems · 9,000 BTU
$699.99 at TOSOT · checked Oct 14, 2026
TOSOT Cosmo 9,000 BTU wall mount system (TST-SU-C9K23) is a 9,000 BTU system from TOSOT Cosmo. It has a wall mount indoor unit, runs on 208/230V, is rated 20.5 SEER2, has an HSPF2 of 8.8, uses R-32 refrigerant, and comes with a 16 ft line set. Lowest in-stock price on file: $699.99 at TOSOT (checked Oct 14, 2026).
| Category | Single-zone systems |
|---|---|
| Model number | TST-SU-C9K23tosotdirect.com |
| Size ? | 9,000 BTU/htosotdirect.com |
| Indoor unit style ? | Wall mounttosotdirect.com |
| Voltage ? | 208/230Vtosotdirect.com |
| SEER2 (cooling efficiency) ? | 20.5tosotdirect.com |
| EER2 (efficiency at 95 °F) ? | — |
| HSPF2 (heating efficiency) ? | 8.8tosotdirect.com |
| Rated cooling capacity ? | — |
| Heating capacity at 47 °F ? | — |
| Heating capacity at 17 °F ? | — |
| Heating capacity at 5 °F ? | — |
| COP at 5 °F ? | — |
| Heats down to ? | — |
| Refrigerant ? | R-32tosotdirect.com |
| ENERGY STAR certified ? | — |
| ENERGY STAR cold climate ? | — |
| Line connection ? | Flaretosotdirect.com |
| Line set included | 16 fttosotdirect.com |
| Wi-Fi control | — |
| Indoor sound level (quietest) | — |
| Outdoor sound level | 41 dB(A)tosotdirect.com |
| Compressor warranty ? | — |
| Parts warranty ? | — |
| Warranty if you install it yourself ? | Licensed installer requiredtosotdirect.com |
| Outdoor unit size (W×D×H) | 28.8 × 13 × 21.9 intosotdirect.com |
| Indoor unit size (W×D×H) | 32.9 × 7.9 × 10.8 intosotdirect.com |
| Outdoor unit weight | 52.9 lbtosotdirect.com |
| Sold as | Single product |
| Availability | Sold by several retailers |
Warranty, and installing it yourself
The warranty needs a licensed installer, by TOSOT's own terms.
"Installation, diagnostics, and repair labor must be arranged separately with a licensed HVAC professional of the customer’s choice."
From tosotdirect.com ↗, read 2026-10-14. Terms change, and local law can require a licensed technician for refrigerant or electrical work whatever the warranty says.
Who makes it
Where to buy
Prices are re-checked every week. A date more than a month old means the store could not be re-read, so the price may have moved.
Price history
Price tracking for this product began October 14, 2026. Prices are re-checked every week, and the chart fills in from the next check.
Every recorded price change (1)
A row is recorded only when a store's price or stock changes; each line then runs to the date the store was last checked. Amazon prices aren't shown (store policy).
Where this came from
confirmed The part number and every spec shown were read from the brand's or a store's own material: a product page, a spec sheet or a product feed, or an archived copy of one. Last verified 2026-10-14. What the labels mean.
The equivalent in other lines
Same category, same size (9k), wall mount, 208/230V, from other lines; cheapest first, at most two per line. Open any of them side by side with this system, or tick several to compare up to four.
| Logo | Brand | Product | Category | Photo | Price |
|---|---|---|---|---|---|
| TURBRO | 9,000 BTU wall mount system TURBRO Finnmark Side by side → | Single-zone systems | $499.99 | ||
| TURBRO | 9,000 BTU wall mount system TURBRO Greenland Side by side → | Single-zone systems | $599.99 | ||
| DELLA | 9,000 BTU wall mount system DELLA Serena Side by side → | Single-zone systems | $679.96 | ||
| DELLA | 9,000 BTU wall mount system DELLA Serena CloudAir Side by side → | Single-zone systems | $679.96 | ||
| DELLA | 9,000 BTU wall mount system DELLA Vita Side by side → | Single-zone systems | $699.96 | ||
| DELLA | 9,000 BTU wall mount system DELLA Umbra Side by side → | Single-zone systems | $709.96 | ||
| DELLA | 9,000 BTU wall mount system DELLA Vario Side by side → | Single-zone systems | $729.96 | ||
| MRCOOL | 9,000 BTU wall mount system MRCOOL Advantage 5th Gen Side by side → | Single-zone systems | $743 | ||
| Pioneer | 9,000 BTU wall mount system (WYT-20U) Pioneer Diamante Essenza Side by side → | Single-zone systems | $808 | ||
| Mitsubishi Electric | Hyper-Heating 9,000 BTU wall mount system Mitsubishi Electric EX Side by side → | Single-zone systems | $818.25 | ||
| Pioneer | 9,000 BTU wall mount system (WYT-20S) Pioneer Diamante Pro Side by side → | Single-zone systems | $868 | ||
| ACiQ | 9,000 BTU wall mount system ACiQ single-zone (no series name) Side by side → | Single-zone systems | $929.99 |