Best Boat Engine Compartment Heaters | LakeWizard

Anyone who is wondering what the best boat engine compartment heater might be for their boat is going to have several options from which they can choose.

Keeping your boat in top shape is just as important during the winter months as it is during the summer ones. Even if you aren’t using your boat as much – or maybe not at all – it’s important to make sure it’s still being maintained, especially when the weather begins to turn cold. Investing in an engine compartment heater is one of the best ways to do this, but many boaters can feel intimidated when it comes to deciding which engine compartment heater is the best for their boat.

The 4 best engine compartment heaters are:

  • the Extreme 400W Small XHEATER Bilge Heater
  • the SEEKR Caframo Boat Engine Compartment Heater
  • the Extreme 600W Medium XHEAT Bilge Heater
  • the Hornet 45 700W Waterproof Enclosure Heater

Like a car or any other motorized vehicle, a boat that isn’t being used can be susceptible to issues just as quickly as one that’s being used frequently. Though water is often the cause of boating malfunctions, so too is winter weather, lack of use, and cold air. Engine compartment heaters have become a popular way of ensuring that a boat is properly winterized and will be ready to roll (or float!) in the spring. But making sure you buy the right one for your craft is important, for your boat as well as your budget.

I love the water and spending time on it in my boat. But, when fall comes I need to spend some time and money making sure I leave my boat in the best shape possible for the cold and boatless season ahead. I’ve recently spent some time researching which engine compartment heaters will work best for my boat this winter, and hopefully you’ll find one on this list that works for you as well.

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What Are the Best Boat Engine Compartment Heaters?

Engine compartment heaters are small block devices that are designed specifically to keep your boat’s engine from freezing during winter months, something that could be disastrous later on.

Not only will a frozen engine need major overhauling in the spring, it’s also possible that a frozen engine will leak fluids and cause other damage on your boat that could be preventable if you were to invest in an engine compartment heater.

There are other ways you can keep your boat’s mechanical parts from freezing in the cold winter months, but most of them are either time-consuming or potentially dangerous.

Some boat owners try their hand at keeping their engine from freezing on their own. They will spend hours using hair dryers, small portable heaters, or even light sources to warm the engine components enough so they will not freeze when the temperatures drop below freezing point.

Again, though, these methods can be cumbersome, impractical and possibly cause more damage if something were to go awry.

Wouldn’t it be better to just invest the money in buying a good engine compartment heater? And invest the time in finding the right one that is going to work for your boat and your budget?

Another advantage to an engine compartment heater is that it will allow you to still take your boat out in the winter months if you live in a place where later season trips are possible.

For many of us, once we’ve winterized our boat for the season, we won’t be boarding it again until spring. But for those lucky boaters that live in a spot where winter boating is an option, having an engine compartment heater means that you can still access your boat on those days that are more mild and boating is still going to be an activity to enjoy.

By having an engine compartment heater, these folks won’t have to fully winterize their craft. They know it will be ready for those quick weekend trips when the weather allows.

The types of engine compartment you will need to buy will have a lot to do with the size of your boat, what area of the county you live, and where your boat is located.

Bigger boats will clearly need larger engine compartment heaters than small ones. Also, boats that are going to spend the winter in colder areas of the country, or are only stored outside will need a more substantial heater than ones that are docked in warm winter locations or are kept inside a garage or storage facility.

Smaller engine compartment heaters will be best if you have a ski boat, a compact wakeboard boat or even many fishing boats that have motors on them.

A medium engine compartment heater will work great for mid-sized cabin cruisers, and many of the more popular runabout boats.

And a large-sized engine compartment heater will be needed if you have a boat that has more than one engine attached, or if it’s a cabin cruiser that’s more than 35 feet.

So, how can you decide which boat engine compartment heater is going to work best for you and your boat? Luckily, I’ve taken some of the guesswork out of this for you.

1. Extreme 400W Small XHEAT Bilge Heater

Extreme is a leader in boat engine compartment heaters, and for good reason. They have an excellent reputation for quality boat engine products and consistently rank high in the industry for not only their well-made heaters, but also for their customer service and sales force.

These heaters are forced-air heaters, meaning that they use the outside air as the heat source when in operation.

The intake system of the Extreme 400W Small XHEAT Bilge Heater pulls in air from outside and uses it as its transfer heat medium.

There’s peace of mind with a heater that’s as sophisticated as the Extreme 400W Small XHEAT Bilge Heater. Once the outside temperature falls below 40 degrees, this compartment heater will automatically switch on.

And, once the temperature surrounding the Extreme 400W Small XHEAT Bilge Heater heats to 60 degrees, it will automatically shut off. There’s no need for your involvement. The Extreme 400W Small XHEAT Bilge heater does it all, and by functioning so effectively, you won’t ever have to worry about freezing engine parts or the potential damage that could result from such a situation.

As the name implies, this heater is going to be best for smaller crafts, since it runs on 400 Watts and has a BTU of 1365 units, which is ideal for a boat that is below 20 feet.

The Extreme 400W Small XHEAT Bilge Heater sells for around $350 and is easy to set up and operate. The Extreme company has a generous money-back guarantee that will make any customer feel comfortable investing in one of their products.

2. SEEKR Caframo Boat Engine Compartment Heater

SEEKR Caframo Boat Engine Compartment Heater
SEEKR Caframo Boat Engine Compartment Heater

Another great option for smaller boats is made by Caframo, another well-known name in the boat accessories industry.

The SEEKR by Caframo is similar in size to the above model. It also has an output of 1365 BTUs. which is perfect for keeping smaller engines from freezing, and it is 400 watts as well.

But – a big difference between the SEEKR by Caframo and some of its competitors is its price tag and its attention to safety and detail.

The SEEKR by Caframo has two fans inside of its main frame. This means that if one fails for any reason, the second fan will activate, which allows for much more peace of mind when the temperatures drop and you may be worried about the functionality of your boat engine’s compartment heater.

This heater also has an automatic turn-on valve that will activate as soon as the interior-sealed thermostat reads any degree less than 45 degrees fahrenheit.

For many boat owners, having a boat engine compartment heater that turns on at 45 degrees fahrenheit is a huge relief, as many don’t turn on until 40 degrees fahrenheit or even below that.

Those few extra degrees can make a boat owner feel much more comfortable, especially in areas of the country where temperatures can drop quickly, and the heater may not have a chance to catch up if it doesn’t turn on a bit pre-emptively.

Another key component of this heater is that there will be no concern of a build up of gas fumes with the SEEKR, since it’s an air-forced engine compartment heater that is spark safe, self-enclosed, and each unit is highly tested before being shipped.

The SEEKR by Caframo normally retails for around $200, which is considerably less expensive than many of the other boat engine compartment heaters that are comparable to this one in quality and design.

This heater will be perfect for those boats that are smaller than 24 feet.

3. Extreme 600W Medium XHEAT Bilge Heater

Extreme 600W Medium XHEAT Bilge Heater
Extreme 600W Medium XHEAT Bilge Heater

As I stated before, there’s a reason why Extreme is one of the leaders in the boat engine compartment heating fields.

Their products are well-made, are extremely reliable, and they have a customer service support team that seems to be able to answer just about any question brought to them.

Extreme is a trusted company when it comes to keeping your boat mechanics safe in the winter.

This particular Extreme boat engine compartment heater is made for a larger boat than the one I previously suggested. Though both are awesome heaters, the Extreme 600W Medium will provide more heat-coverage for larger crafts to ensure that an adequate amount of warm air is being distributed to a larger vessel.

Not only is this Extreme engine compartment heater a 600 watt model, it also has an impressive BTU of 2043, which will allow it to heat a square foot space that is significantly larger.

This will result in your boat’s engine and any other mechanical parts being fully covered in the event of a temperature drop that is significant enough to need a heating source to keep all mechanical operations intact and functioning.

It also has an automatic shut-off that starts when the air around the engine reaches 40 degrees fahrenheit.

Some boat experts may feel this is too low, and that the unit should switch on when the temperature reaches around 45 degrees fahrenheit. This may make you decide that this is one of the drawbacks to this particular engine compartment heater.

But, if the 40 degree fahrenheit shut-off point is acceptable to you, then consider the Extreme 600W Medium XHEAT Bilge Heater as the best boat engine compartment heater for your mid-sized craft.

This heater is made to perform – and it will be a reliable engine compartment heater for years to come.

The Extreme 600W Medium XHEAT Bilge Heater typically sells for around $500, making it extremely competitive with other boat engine compartment heaters of its size, performance and caliber.

4. Hornet 45 700W Waterproof Enclosure Heater

Hornet 45 700W Waterproof Enclosure Heater
Hornet 45 700W Waterproof Enclosure Heater

For those of you who have larger boats, or want to make sure that your engine will be protected even during the most extreme weather patterns, the Hornet 45 700W Waterproof Enclosure Heater is going to prove to be an excellent choice for keeping your boat’s engine compartment warm during inclement weather.

As the name suggests, the Hornet 45 is one hundred percent waterproof, which is ideal for those boat owners who have crafts that stay docked in water trough the winter, or those of you who may even be living on your boat throughout the year and know that cold weather may also be synonymous with rough water times.

This unit, which is completely designed, manufactured and assembled in the United States, is great for house boats, large yachts or for sailboats that are used as personal living quarters as much as they are used for recreational purposes.

At 700 watts, the Hornet 45 heater is one of the largest on my list, but doesn’t feel cumbersome. It is easy to mount when needed, as well as to disassemble and store during the months when a boat engine compartment heater isn’t necessary because the temperatures are no longer threatening to your boat’s mechanical parts and ability to operate effectively.

Made from high-grade stainless steel, the Hornet 45 700W Waterproof Enclosure Heater will automatically turn on when the temperatures around it reach 40 degrees fahrenheit, and will turn off when the thermometer climbs to 60 degrees fahrenheit.

Another great perk of this heater is that it has a 20 foot cord, making it possible to run the heater from an electric source off the boat if necessary.

Its extended cord length and the fact that it’s waterproof means that this engine compartment heater is more versatile than many of its competitors.

Some of the loyal customers of this heater have mentioned using it in workshops, barns or basement areas where there was water pooling and they would have been hesitant to use a space heater or other source of warmth to keep an area warm when safety was of top concern.

The Hornet 45 also comes with a money-back guarantee and a customer service line that makes others pale in comparison. Any question that can’t be answered on their website is quickly addressed by one of their competent and friendly customer service members.

Retailing at around $230, the Hornet 45 is extremely reasonable in price and the reliability and versatility should be heavily considered if you are in need of a larger and more powerful boat engine compartment heater for your rig and don’t want to blow your budget in the process.


Brian Samson

Brian Samson

I have a deep love of houseboating and the life-changing experiences houseboating has brought into my life. I’ve been going to Lake Powell on our family’s houseboat for over 30 years and have made many great memories, first as a child and now as a parent. My family has a passion for helping others have similar fun, safe experiences on their houseboat.

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