On-board air conditioning in some climates is fast becoming a necessity rather than a luxury and can mean the difference between an uncomfortable and enjoyable cruise. Whether buying an air conditioning system for the first, second, third or tenth time, outfitting a boat with the latest gear should be part of the fun, not a chore.

Do I need one?

Don’t be fooled by the common misconception that air conditioners simply cool the air – there’s a lot more to it. In colder climates, quality A/C systems can also provide year-round heating. In addition to cooling, air conditioning systems also control humidity, which is high when in close proximity with water. Marine air conditioning removes moisture from the air prevents dampness, rot, mold and mildew.

What kind of system is best for my boat?

There are many air conditioning products available on the market, but when determining which type of system to buy, the size of your yacht is very important. Utilizing the vast amount of water provided by the sea, most marine air conditioning systems use water cooling methods rather than air and this allows us to build a more compact unit to suit small on-board spaces. Self-contained systems are the best choice for smaller boats up to 40ft due to the lower cost and easy DIY installation, which is usually under a bunk or settee. Larger yachts up to 80ft should consider split-gas air conditioning systems, which have the condensing unit in the engine room and air handler in the living space. For larger boats and super yachts, chilled water systems are the ideal option and can be tailored to specific needs.

Which one should I get?

We all want to save a few bucks, especially at this time of year, but the cheapest option is not necessarily the best. Remember that buying an air conditioning system is not something that should happen often, so do your research. High-quality, innovative engineering is a must as is a manufacturer’s history in producing rugged systems that can withstand the harsh marine environments and work efficiently with the boat’s power source. Check out the brand’s reputation and whether it has a geographically broad service network– you never know when and where you might need it. For example, Dometic Marine has an extensive worldwide distributor and dealer network for its premium brands, to ensure that service and support are available anywhere in the world.

What maintenance is required?

When an air conditioning system has been installed and is working, the last thing a boat owner wants to worry about is carrying out endless maintenance checks. If the air conditioning unit is properly manufactured to a high standard, then only minimal maintenance will be required to ensure maximum performance and longevity of the system. Throughout the season the seawater strainer should be checked and emptied regularly to maintain good water flow, and the air filter should be cleaned or replaced periodically to maintain good air flow. For boat owners with self-contained systems, some DIY summer and winter preparation is recommended such as checking the thru hull and heat exchanger for any debris pulled in with the seawater as well as making certain the condensate pan is draining properly. Also check the system’s hoses, coils and other piping for leaks. In winter, you should run a little biodegradable antifreeze through the unit. Maintaining a split-gas system takes a little extra effort because the components are located in different parts of the boat, but the principles remain the same. In addition, check to ensure there are no refrigerant leaks between the components. A chilled water system will require regular service checks by on-board or local service engineers due to the complexity of the system.

What about electrical requirements?

The electrical consumption of air conditioning units depends on the size of the air conditioner but most run on alternating current (AC) power and come in different power configurations. Check out the specification sheets for the running current information for the unit and advice on how to select the right circuit breaker, but also make sure a generator, inverter or shore cord can handle the inrush current of the compressor when an air conditioner starts. Soft start technology reduces the in-rush of current caused by large compressor motor loads, therefore reducing and balancing the strain of the boat’s power source.