How to Choose the Right Boat Heater

It’s summer now, so a boat heater might not be the first thing on your mind but fall and winter are on the way and it’ll be here before you know it! If you want to keep the boating season going all year, consider adding a boat heater to your arsenal. The boat heater you choose will determine how effective it is for your specific conditions, so you want to pick the right boat heater. There are several factors to consider for choosing the right boat heaters. We’ll cover the most popular considerations in this article. 

Why Buy a Boat Heater in the First Place?

boat in winter

A boat heater ensures your boat's health by keeping your boat's engine and critical components safe from freeze damage. A boat heater will help protect your boat in the winter, but can also keep you out on the water longer, once it starts to get colder and darker outside. With all these perks, you might think it’s a costly investment. But for only pennies a night, our boat heaters keep your engine safe and your boat ready for the next boating trip. One testimonial mentions using our XXHeat 600W for their winter days and not even needing to winterize thanks to his Xtreme engine compartment heater. 

If you’re unprepared for winter this year, a freeze can cost you thousands of dollars in repairs and weeks off the water. Freezing temperatures cause damage to your engine block, exhaust components and other critical boat equipment as well as decrease your battery’s life. Although light bulbs and household space heaters might seem like an easy  solution, they can easily lead to a fire or explosion. Appliances built for homes are not ignition protected and produce heat at temperatures that are dangerous in any space that may contain fumes that could be ignited.  That’s why choosing a heater specifically made for boats will not only save your boat from freeze damage but will do it safely and without the fire hazard standard household products create. Xtreme Heaters have created the safest, most reliable, and most efficient boat heaters available. 

What to Look For in a Boat Heater?

There are many characteristics to consider for a boat heater. At Xtreme Heaters, we make our recommendations based on your boat and engine compartment configuration. It’s up to you to factor in the variables we can’t like storage location, local weather conditions, and extreme weather. It’s why we’re happy to supply you with the knowledge of our heaters to help you make an informed choice. But only you, as the boat owner, can make the right boat heater choice for your vessel and local conditions. While there is no precise science to heater placement and installation the goal should be to maximize circulation of the warm air the heater generates. The more circulation there is, the more even the temperature will be in the engine compartment, and the better the protection for everything in it. 


The size of the boat and more importantly the engine compartment should be the first quality you should consider when selecting your boat heater. At Xtreme Heaters, we have three sizes to mix and match to meet your needs. The small XHeat with 400 watts is perfect for boats up to 24 feet. The XXHeat is our medium size to provide 600 watts to boats of 21 feet to 28 feet. The last and biggest option is the large XXXHeat for 800 watts to serve boats over 28 feet. The beauty of having these three various sizes is the ability to mix and match to combine the right heaters for your boat and engine/equipment spaces. 

Type of Boat

The type of boat you have will also determine which boat heater will be the right fit for you. The small XHeater is great for ski/wake boats, runabouts, and deck boats with smaller engine compartments. For medium boats like runabout boats and “pocket” cruisers, the medium XXHeater provides a bit more capacity for those boat types. Our largest option is the XXXHeat and is a great option for larger cruisers, trawlers or motoryachts, with multiple engines, and large engine spaces. 

ski wake boat on the water

Ski and Wake Boats

Because ski and wake boats have a small engine compartment or just an engine cover over the motor, our small XHeat will do the job. But if your boat is stored on a lift or trailer in the winter, it’s smart to choose a boat heater the next size up. This would make the medium XXHeat a better option for your ski or wake boat stored on a lift or trailer. 




The engine compartment in a runabout typically extends the full width of the boat. This setup requires a higher volume of heat, which is why the XXHeat medium heater is perfect for your runabout. As mentioned above, depending on how it’s stored and how extreme the conditions are in your area, you might need to size up to the large XXXHeat. 


Cruisers have a variety of shapes, sizes, and engine configurations. At Xtreme Heaters, we qualify a cruiser as Express Cruisers, Trawlers, Sedan Bridges, Convertibles, Aft Cabin, or Sport Fish models manufactured by Sea Ray, Chaparral, Cobalt, Regal, Bayliner, Four Winns, Crownline, Larson, Rinker, etc. 

Typically, most cruisers have more space in the engine compartment which allows for more mounting options with your boat heater. Assess your engine compartment to determine the best placement for your boat heater. You want to protect the water jackets of the engine and pumps so the heater should be placed where direct airflow hits the lower portion of the engine, without placing it so closely that the air doesn’t circulate within the compartment.  With some cruisers, the generator or other equipment can block the airflow. If that’s the case, try to redirect the airflow to the underside of the motor in the direction of that additional equipment. The goal is to have even airflow to the equipment you wish to protect. 

Twin-engine cruisers are a different story. There are multiple options for heater placement with two engines. One option is to use one Xtreme Heater for protection. One single heater can be placed between the two engines to blow from the front. This will create a pattern of circulation to evenly distribute heat throughout the entire compartment. If you choose the second option of two heaters, you can place them outboard of the engines and face in opposite directions. This creates a circular flow of air in the engine compartment. Read more about cruiser heaters in our installation guide


For houseboats, you’ll want the circular flow we mentioned above. You can achieve this by mounting two Xtreme Heaters outside of your engines. One will be pointing forward and the other pointing aft. This creates a circular flow, which will help maintain an even temperature control throughout the engine compartment. 

houseboat boat heater flow

With houseboats, it’s also important to consider wires, vents, and hatches when permanently installing your Xtreme Heaters in a houseboat. You can read more about that in our installation guide for houseboats. 

If you’re going back and forth between which heater to choose for your boat, check out our testimonials to see the boat and heater combinations our customers have found to be successful. 

Why You Should Choose a Boat Heater with Xtreme Heaters

When you purchase a boat heater with Xtreme Heaters, we guarantee satisfaction with all our products with a 2-year warranty. Our products are easy to install with no tools and are reliable even in the harshest conditions. Our boat heaters are certified and independently tested to meet or exceed Coast Guards or ABYC standards. But, we went further and also tested our products against Military Specification (MILSPEC)  ratings for heat, cold, moisture, and vibration. Our products passed all these tests with flying colors! Our mission at Xtreme Heater was to build the safest, most reliable, and most efficient product available.  Read our numerous testimonials vouching for our Xtreme Heaters and the creative ways people use Xtreme heaters for their boats, cars, RVs, and more. 

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