Dometic Brisk II ‎(B57915.XX1C0)

The Dometic Brisk II resembles an AC unit on a camper or RV, but this one goes on the roof of your boat.

It is a perfect replacement for an existing roof-mounted air conditioner unit, and I really like how easy it is to add to a boat without air conditioning.

Not all boats can support a roof-mounted marine air conditioner. However, this air conditioner does not take up space inside, and it is easily accessible to work on.

The condensing and evaporator unit is housed entirely on the roof and is shielded from the elements with a cover.

One thing that some people do not like is that the air conditioner is visible from the outside.

However, I don’t mind it on some boats because the white cover keeps the unit from sticking out like a sore thumb.

The noise level is also a common complaint, but it’s about as loud as a typical window air conditioner.

All that you will see inside the boat is the ceiling-mounted vent and the air conditioner controls.

The indoor trim is called a distribution box and provides a way to direct airflow (I often compare it to the air vents in a car).

The air conditioner’s manual controls are also mounted on the distribution box.

The Dometic Brisk II requires a 14" X 14" hole in the roof with structural supports.

The boat's roof must be able to support about 75 lbs, and there must be space to run electrical wires.

If you are comfortable making a couple of cuts in the boat, then this can be a DIY job.

I'm pretty daring, but this is one of those projects that could turn into a major undertaking.

Also, remember that lugging this thing onto the roof alone may be difficult, so be sure to guilt a friend into helping.

Alternatively, the Brisk II can connect to ductwork. This would require your boat to have air ducts running up to the roof, as well as a thermostat mounted on a wall.

Although I like the cleaner look of a ducted system, few boats have ductwork running to the ceiling.

If you don’t have ducts already running to the ceiling, then I would stick to a self-contained marine air conditioner, like the SEALAND ECK16K-HV.

SEALAND ECD16K-HV 

The Sealand ECD16K-HV is my top choice for retrofitting an old marine AC system—especially if you're swapping out a self-contained unit.

It’s nearly twice the price of the Dometic Brisk II, but if you’re after something more refined with reverse cycle heat, it’s worth a close look. Sealand actually became part of Dometic in 2017, so you may see this model number marketed under either name.

This model replaces 12,000 to 16,000 BTU units and includes a sleek digital display and new control.

It cools efficiently and doubles as a reverse-cycle heater—great for extending your boating season into chillier mornings. The high-velocity blower can be rotated for horizontal or vertical duct setups, and the remote-mount electrical box gives you some much-needed flexibility during install.

I like how compact this Sealand model is. It doesn’t hog cabin space, and the stainless steel drain pan means you won’t be dealing with rust issues down the line.

You also get a pre-installed return-air filter that’s easy to pop out and clean—no tools or frustration required. 

It runs on R-410A, which is more environmentally friendly than the old-school refrigerants, but is still being phased out completely by 2036, so that's something to consider.

The Sealand model just feels like a modern, well-thought-out unit. While it's designed as a retrofit, it can also be used as a brand-new AC install if you’ve got ductwork or are planning to add it.

Just know it’s not exactly plug-and-play—there’s still wiring and ducting involved.

Still, if you're upgrading from a similar system, it’s about as smooth a swap as you could hope for. If the Brisk II is the rugged workhorse, this is the polished pro-level option that’s quieter, more efficient, and built to last.

Dometic ECD Self-Contained Air Conditioner

The Dometic ECD might not mount to your boat's roof like the Brisk II, but it packs a serious punch below deck. 

This is a self-contained marine air conditioner, which means everything—the compressor, evaporator, and condenser—is built into one compact box.

You’ll need to install it securely—typically under a bunk or in a locker—but once it’s in place, it operates quietly and stays out of sight while keeping your cabin comfortable.

Now, let’s talk brass tacks: this unit is part of Dometic’s EnviroComfort line, which is what the “ECD” stands for.

It’s built to marine standards and built to last, with corrosion-resistant stainless steel components that can handle salt air and wet conditions without turning into a rust sculpture.

You’re paying for that durability though—this model comes in at a premium price of over $2700. It’s definitely not the budget option, but you get serious reliability and performance for the money.

I’m focusing on the 16,000 BTU version, which is a great fit for larger cabins or smaller boats with a single zone. It’s versatile enough to be used in an RV, but it’s truly designed with marine use in mind.

One of my favorite features? It has reverse cycle heating, so you’re not just cooling off in summer—you’re also warming up in shoulder seasons. 

However, keep in mind that reverse cycle heat relies on water temperature, so when the water dips below 40°F, this system starts to tap out on the heating front. If you're boating in chilly conditions, you’ll want a backup plan.

Installation-wise, you’ll need a 230V power source, which means this is for serious setups—not your average trolling motor battery connection. Still, if your boat is wired for it, the ECD offers a lot of comfort in a relatively small footprint.

This is a high-end, all-in-one climate solution, perfect if you want powerful cooling (and some heating) without cutting holes in the roof or routing ductwork all over the place.

Just be sure to factor in the power requirements and that hefty price tag before you commit.

Ivation IVACA6500

The first time I saw the IVACA6500, I mistook it for a U-shaped home window air conditioner.

It works just like a window air conditioner, with the condenser sitting outside and the evaporator inside.

The only difference is that the IVACA6500 actually has two separate parts connected by a rubber tube, similar to a mini split setup.

This makes it ideal for marine applications, thanks to the flexible mounting system.

The most important thing that may be a problem is the need for a window that opens to pass the connections through.

I found installation to be super simple, though, thanks to the included adjustable brackets.

These brackets allow for placement adjustment by clamping the unit to the window.

However, I recommend placing the unit below the window and modifying the brackets to mount it in a more discrete location.

After you get the unit mounted, just plug it into a 120V outlet and fire it up. The digital thermostat on the front can set the air conditioning to a desired temperature.

However, I find that these thermostats are not nearly as accurate as wall-mounted ones used in traditional AC systems, like Dometic.

As a light sleeper, I highly recommend this unit for a bedroom thanks to its quieter operation at 55 dB.

I suggest setting the timer to turn the air on an hour or two before bed so it is nice and cool, then take advantage of the sleep mode to quiet the fan noise.

During the day, I find it much better to use the dehumidifier mode.

I like the IVACA6500's dehumidifier mode since it is perfect for keeping the boat nice and dry on those temperate days.

Some people do complain about the look of the outdoor condensing unit, but at least it doesn’t obstruct the window.

I personally don’t think it looks bad, and it is easy to remove the unit in the cooler months.

At only 6,500 BTUs, the Ivation IVACA6500 will cool a room or a small boat. One good thing about the smaller units is that it doesn't need a ton of electricity to keep it going.

With that in mind, you are still stuck running on shore power with this air conditioner.

MarinAire Self-Contained

The MarinAire is my favorite self-contained air conditioning unit, but it is unique.

The compressor and coils are protected by a molded plastic case, which definitely adds some protection.

The case also helps to keep the noise level down when the air conditioner is running.

The MarinAire is also the most compact marine ACs I've come across.

It will fit in tight compartments or under benches where other self-contained systems can't.

I also like the hook on top, which is a lifesaver when lowering the air conditioner into the cabin. It really turns the installation into a one-man job.

The standout features are the built-in pressure gauges to quickly check the high and low pressures without special tools.

I’ve looked at a lot of marine air conditioners with varying features, but the Marinaire has some of the best features included, such as a wireless remote.

It also comes with a conventional thermostat for the wall.

The Marinaire is the only marine AC unit I have seen with wireless connectivity.

You can control the marine AC unit from anywhere with the included WiFi thermostat (assuming you have internet access).

Installation is also a breeze since this is a self-contained unit.

The main components not included are some pipes for the stainless steel drain pan and water cooling, as well as a pump.

From there, all it takes is running the pipes and wire for the thermostat and humidity sensor wiring to the cabin.

Finally, connect the duct (size varies by BTU) and plug in the marine AC unit to start cooling off.

How many watts does a marine air conditioner use?

The exact number of watts a marine air conditioner uses varies by model and BTUs. For example, a 6,000 BTU self-contained unit uses about 500-550 watts.

How long do marine air conditioners last?

A marine air conditioner’s lifespan hinges largely on how well it is taken care of. The average life is about ten years, but this may vary depending on how much use it gets.

How do you size a marine air conditioner?

You size a marine air conditioning unit based on the cubic footage of the boat, as well as sun exposure and climate. A quicker and easier way to get in the ballpark is by multiplying 5 BTU times the square feet of the boat.

How do you maintain a marine air conditioner?

The most important part of maintaining a marine air conditioning unit is to clean out the return air filter and keep the condensate pan clear. Be sure that water does not freeze in the pump or pipes during the winter.

What is the difference between refrigeration and air conditioning on a ship?

Refrigeration and air conditioning are often used interchangeably when discussing cooling systems on a ship.

However, the word refrigeration is mainly used when talking about cooling systems like freezers and other cold storage. In contrast, air conditioning commonly refers to regulating temperatures in a living space.