Best Bilge Heater For Boats In Winter

Most boat owners know that cold weather can cause a lot of damage to your boat. However, when in-between seasons, when the temperature can go from 60+ during the day to below freezing at night, you can prolong your boating season and minimize the risk of damage to your engine by using the best bilge heater for boats. The best bilge heater can help to protect your vessel from a cracked engine block during the cold night while also allowing you to go boating during the day.

best bilge heater for boats

How To Use Bilge Heater For Boats

Engine compartment or bilge heaters, such as those from Twin Hornet, offer an effective and safe alternative to needing to winterize your boat engine. Bilge heaters cycle on and off when the temperature ranges between about 40°F and 55°F. They are also safer than a 60W light bulb and home space heaters. Many “quick and easy solutions” have caused far too many problems, including fires and sunken boats.

To get the best performance from your boat engine heater, you should place covers over the bilge blower vents of the boat. Perhaps the best method to accomplish this is to have a local upholstery shop or canvas shop make a set of custom, cheap “snap-on” style covers to place over the vents. Whenever you wish to utilize the boat, you simply need to remove the bilge vent covers. When finished, simply snap the bilge covers back into place. This solution allows you to keep the damp, cold winter wind and moisture out of the boat engine compartment, while also keeping the heat in.

Keep in mind that a boat that is stored out of the water will lose heat significantly faster than if the boat were in the slip. For those who store their boat on it’s trailer or suspended on a lift, they should also cover the outdrive unit. You can use a heavy plastic bag or a similar cover on the outdrive. Just be sure to tie it at the top in order to prevent the heat in the engine compartment from escaping through the exposed metal.

If the forecast calls for a freeze, you should also consider putting put your boat back in the water, as water offers greater insulation than air.

Cons Of Bilge Heaters For Boats

The biggest downside with electric bilge heaters for boats is their relatively high power demand. Electric bilge heaters require serious amps to operate properly. It is advised not to run the heater off of the boat battery. Instead, make sure that you have access to a reliable source of shore power.

The potential hazard of causing a fire from an electric boat bilge heater is extremely low if you install and use the heater properly. If the heater falls over, or is placed near combustible fluids, then naturally your chances of causes a fire increase significantly. Be sure to take all necessary precautions before leaving your boat bilge heater running unattended.


Using the best bilge heater for boats in the winter is a great alternative to needing to winterize the boat. Of course, there are certain things to take into consideration, such as your location, temperature, and boat size, which you should examine prior to deciding whether winterizing or using a heater is the best option for you.

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