Boat & Marine AC Repair on Grand Lake, Oklahoma

01 · How Boat AC Works

One box, two jobs: cool air in, hot water out

Your marine AC is a single self-contained unit tucked under a berth or dinette seat — no separate outdoor condenser like a house system has. It does two things at once: cools cabin air and blows it back out, while pulling in lake water to carry the heat away.

1. Your marine AC: a self-contained, water-cooled unit under a berth or dinette seat
2. Lift the lid and there it is — no separate outdoor unit like a house system has
3. A blower pulls cabin air across a cold coil and pushes it back out cool
4. At the same time, lake water is flowing through to carry the heat overboard

02 · Lake Water Does The Cooling

Follow the water, scoop to overboard

Grand Lake water is a marine AC's only way to get rid of heat. Here's the path it takes through the boat, from the intake scoop to the stream you can see running overboard.

1. Cool lake water enters through a thru-hull scoop, past the seacock valve
2. It passes through a sea strainer that catches weed, silt, and zebra mussels
3. A raw-water pump keeps it moving on toward the AC unit
4. Inside the unit, that cold lake water flows through the condenser and carries the heat away
5. Now warm, it leaves through a thru-hull on the side of the hull — the stream you can see running while the AC is on
6. Lake water in, heat out — that's what makes the cabin cold

03 · Why It Has To Be In The Water

No water, no cooling — and a dead pump

Marine AC is water-cooled, so it only works — and it only survives — with lake water moving through it. That's why the boat has to be floating in its slip and hooked to shore power before we'll run or test the unit.

1. Marine AC is water-cooled — it only works, and only survives, with lake water moving through it
2. Picture the lake dropping below the intake — on a trailer, a lift, or in dry storage, that's exactly what happens
3. The pump runs dry, glows hot, and the overboard stream stops — that's a pump about to fail
4. That's why we only run or test a marine AC with the boat floating in its slip and hooked to shore power — never on a trailer, a lift, or in dry storage

Never on a trailer, a lift, or in dry storage. Running the unit dry — with no lake water reaching the intake — can destroy the raw-water pump.

04 · What We Check Dockside

The usual suspects behind a warm cabin

Most Grand Lake service calls come down to one of these. We check them right at your slip — boat in the water, hooked to shore power.

1. A clogged sea strainer is the #1 reason boat AC blows warm on Grand Lake
2. Clear it, and the flow — and the cooling — comes right back
3. We check the intake and seacock too, for the same algae, silt, and zebra-mussel buildup
4. And the raw-water pump itself — a failed pump means no water movement at all
5. Then we glance at the discharge: a steady stream overboard means water's flowing — weak or none, and we've found the problem
6. On the electrical side: the shore-power connection, the cord, and the breakers. Know where yours are already? Bonus — but never required

05 · Ready When You Are

Dockside, at any marina or private dock on Grand Lake

No hauling, no trailering — we come to your slip, wherever you're docked on Grand Lake O' the Cherokees.