Mermaid M6 6500 BTU 230V Cool Only Marine A/C Unit

Downsizing from an oversized AC unit is more common than most boat owners expect, and the Mermaid M9 Cool Only in 110V trim is often the result — 9,000 BTU of straightforward cooling for boats around 30 feet as a cruiser or 32 feet as a sailboat, without the added mechanical complexity of reverse cycle heating built in.

Why Choose the Mermaid M9 Cool Only

Fewer moving parts means one less system that can eventually need service — a real advantage for owners in consistently warm climates with no real use for onboard heating. If your cruising takes you into cooler weather at any point in the year, the Reverse Cycle or Electric Heat versions of the M9 solve that instead, at the same footprint.

Mermaid builds these units by hand in the US, moving roughly 900 to 1,200 units a year across boats from small cabin cruisers up to 75-foot yachts — a detail that matters if lower-volume, hands-on manufacturing factors into your purchase decision.

What to Know Before Installing

• Pump is not included and must be sourced separately
• Ducting requires both 6″ and 4″ runs, with at least three 4″ round supply grilles
• Air discharge position must be specified before ordering
• Since this unit has no heating function, confirm it matches your climate needs — there’s no field upgrade path without swapping the full unit