5 Best Marine AC Units (For A Cool Boating Experience) (2024)

A hot day on the water doesn't have to mean sweating to death. The best marine air conditioners can keep the inside of a boat ice cold even on those 100-degree days.

I know that a marine air conditioner can be an expensive investment that should not be taken lightly.

That's why I made this list of the best marine AC units to help boaters find the best way to stay cool in those hot summer months.

The exact size cooling capacity your boat needs requires a complex calculation.

My general rule of thumb is that one BTU (British thermal units) cools about 5 square feet and heats 10 square feet.

This is based on moderate climate control and cooling an area below deck.

• Large Boats
  The Dometic Emerald Titanium Deuxis perfect for large boats over 500 square feet. I recommend this for a very large yacht with a separate engine compartment and large living spaces. Sometimes, larger boats use two units.
• Medium Sized Boats
  Smaller boats from 200-500 square feet have a few options, including the Webasto AC Retrofit Kitand the Marinaire AC system. These self-contained systems are perfect for small to mid-size boats with room to run a short piece of ductwork.
• Small Boats
  Finally, marine AC units like the Dometic Brisk IIand Ivation IVACA 6500are perfect for small boats in the 100-200square foot range.

I always consider the size of an existing marine AC unit and also perform a new calculator.

There are several formulas that get very scientific, but a simple online capacity calculator is my go-to.[1]

The most budget-friendly marine air conditioners cost less than $1,000, while ducted systems can easily cost a few thousand.

I know most people have a budget in mind with these larger projects. In that case, the budget will dictate what type of system you can get.

A traditional self-contained marine AC system like the Marinaire or Webasto I mentioned above typically costs about $2,500.

Split systems like the Dometic Emerald Titanium Deux cost significantly more.

The exact price varies by dealer as Dometic does not advertise the cost for its high-end split systems.

Continuing on with self contained systems, the Dometic Brisk II is a fairly cheap option as it starts around $1200.

However, the cost to install may be higher than other self-contained systems like the Marinaireand Webasto.

Retrofitting a smaller unit like the Ivation will be the most affordable route. I commonly see these systems for around $700.

Most marine AC units I've found run on a generator, which will add a significant cost if you don't already own one.

Marine air conditioner warranties vary significantly between brands, but most come with at least a one-year parts warranty.

Higher-end models like Dometic's Emerald Titanium come with a parts and labor warranty.

In comparison, companies like Webastoand Ivationhave a parts-only warranty.

One and two year parts warranties are pretty standard in the marine air conditioner industry.

I find that Dometic offers the best marine air conditioner warranty at two years on many of its higher-end products. It is also one of the most inclusive warranties.

Some marine air conditioning systems are easy to install, while others vary in complexity.

More importantly, everyone has a different level of abilities.

People planning a DIY install should first determine if there is room in the boat to mount a self-contained unit. Then, plan where to run the pipes and electrical.

Alternatively, consider a roof-mounted unit if there isn't space for a conventional marine AC unit.

The roof-mounted unit requires a single hole but also requires framing out the roof around it.

Most people don't want to spend days hacking away at their beloved boat, so I would go with the Ivation IVACA6500, or even a portable boat air conditioner.

The most difficult-to-install marine AC units are split systems, where the condensing unit goes in the engine room.

These are more expensive units and difficult to install since pipes must be run throughout the boat.

These may also require extra refrigerant to be added, and the lines must be vacuumed.

I would only recommend this system for really large boats or if it is already undergoing extensive maintenance.

Maintaining marine AC units is similar to keeping up with a home AC system.[2]

The most important thing to do is keep the return air filters clean. I also recommend checking the coils annually to ensure they are not dirty.

A chilled water system such as the Webasto, Marinaire, and Dometic Emerald TitaniumI looked at do require a little extra attention, such as ensuring the water does not freeze in cold months.

I am a fan of low maintenance, and you can’t get much simpler than the Ivation IVACA 6500 and the Dometic Brisk II.

Both marine AC units are easy to access, so filter cleaning requires little effort.

The good thing about most marine AC units is that they are serviceable.

Most marine AC systems mentioned above have service ports so an AC tech can easily perform a check-up and get the system running like new again.

Self contained marine air conditioners like the Webasto and Marinaire place the condenser and blower in a single package.

Most marine air conditioners rely on seawater to cool the returning refrigerant. These units are very efficient, quiet, and compact, which is perfect for a boat.

Adding this type of marine air conditioner is also very easy, even if your boat never had air conditioning.

All that they require is a hose for the seawater, electrical, and a hole for the vent.

Using a vent means self-contained units are great for directing airflow to a specific part of the boat.

It is also worth noting that self-contained units can also refer to portable, roof-mounted, or hatch-mounted systems where the condenser and evaporator are together in one assembly.

A boat hatch-mounted marine air conditioner is designed to fit into a boat’s existing hole in the roof.

These units are very easy to install, but they come with a few challenges.

Hatch mounted air conditioners are essentially a window AC unit with an angled duct that attaches to the boat's hatch.

Chilled water units are some of the most popular marine AC systems, and chilled water may be used on both split and self-contained systems.

A pump takes seawater and pushes through copper piping on the chiller, known as a heat exchanger.

Instead of using large condensing coils like your home's AC system, the seawater cools the coils, so there is no need for a fan.

Besides heat transfer, chilled water units still operate like most other air conditioners.

For instance, they have a compressor, evaporator coil, and a reversing valve (on heat pump models).

To boil this down, chilled water units are perfect for boats because there is a constant supply of water to keep the system cool.

This also removes the need to place a condensing unit outside since the seawater literally removes heat from the boat.

A split-air unit is simply an air conditioning system where the condenser and evaporator are separate.

In most applications, the condenser coils and compressor are outside, while the evaporator coils and air handler are inside.

This is the exact opposite of a self-contained marine air conditioner. However, it can use either a chilled water system or an air-cooled condenser.

I don’t want to make this too complicated, but the Ivation we covered is technically a split system since the condenser and evaporator are separate.

However, a more conventional example is the Dometic Emerald Titanium DEUX.

Split systems are ideal for larger vessels with an engine room or boats with multiple evaporator units.

I recommend against these complex split systems for many boaters because they are very complicated, and repair can be costly.

The best marine air conditioner will depend on your boat’s size and needs. I like all of the marine AC units that we covered, but each one really fits a specific need.

However, I find the MarinAire Self-Contained system to be the best marine air conditioner because of its casing and integrated gauges.

But best of all, it is easy to install.

I also like the units built by major brands like Dometic marine air conditioners because they are well-built for a harsh marine environment and offer an excellent warranty.