Diesel Heater

Keeping Warm and Dry

On cold nights, what is more comfortable than a fire?  


The diesel heater burns the air in the cabin and sends it up out the chimney. Then the box becomes very hot which warms the boat. As it burns, it sends the cabin air outside through the chimney and causes the dorades to draw air in. This fresh air is dry and clean, which leads to the boat becoming filled with warm and dry air. 

It is amazing how fire can make a space change from habitable to comfortable. 

Dinghy Heat Shield

Our dinghy lives on a rack mounted above the chimney for our heater. This is not a problem in the warmer months, when we are using the dinghy often and the stove is off, but it can pose a bit of an issue in the cooler months when we would be running the heater to keep us from freezing inside the cabin!

The heat leaving the chimney is pretty darn warm. According to a thermal gun, the chimney itself gets up to around 300F, and the carpeting over the dinghy bedrail was getting up to 180F until we shut the heater down to save the carpeting! This test was performed without the dinghy in place, as we did not want to risk harming the fiberglass hull with this heat.

To allow us to heat our home while we cruise with the dinghy on the deck, we opted to install a heat shield. 


The concept was simple, the heat leaving the chimney needed to be blocked from rising into the dinghy. It needed to be open to the sides that way the heat could be vented away, and it had to be able to surive in the marine environment. Lastly, it had to be inexpensive as we are currently cruising on a tight budget! 

A visit to True Value brought us to our solution! We bought an aluminum baking sheet for a few dollars and secured it in place! The rolled edges of the pan will avoid any injuries to our shins as we walk around this area of the deck, and the aluminum itself will not rust away in the salt air. The large surface area of aluminum will also act as an efficient heat sync, dissipating the heat from the chimney as we sail. 

To test out the setup, the heater was ignited and allowed to get up to temperature. The heater itself was 550F, while the top of the chimney was only 120F. The air coming out of the chimney was a sturdy 200F and the heat shield stayed at 100F for the duration of the test. Best of all, the carpet never got above 90F (which was the ambient temperature on that day). To keep the aluminum slightly off the rail, I cut and re sawed a 2x4 to create small wooden spacers that would provide a dead air space for heat to escape from. This increases the air flow between the aluminum and the carpet, keeping everything cooler.  


The top of the chimney might seem a bit close to the heat shield, but this isn't a large concern as most of the exhaust exits the bottom of the chimney top. 


To hold it all in place, I used stainless steel seizing wire, as it allows me to tie a tight lashing, just like with rope, but it will be immune to the heat from the chimney. I tied it very tight that way the pan would not spin or shift around and so that the metal wires would sink into the carpet, remaining slightly in relief of the dinghy hull above. 

With the heat shield in place, we feel safe lighting the heater with the dinghy on the deck, knowing that the fiberglass will not catch on fire as we try to keep warm. One other point of mental peace is we won't be using the heater unless it is cold outside, and these cold days will mean a more efficient heat transfer from the aluminum to the air.  

Heat shields are very useful tools on a boat. They can allow you to have a very hot object placed very close to heat sensitive materials without the fear of damage or fire. 

Overfilled Diesel Heater

If your heater accidentally fills with fuel with the flame off, you can create the potential for a real problem. If you try to act smart and throw a flaming paper into the fuel to act as a wick, you will be sorely punished by an out of control blaze until the fuel burns off. Instead of dealing with such a massive fire inside the heater, the alternative is soak up the fuel with a toilet paper roll and then continue to use as normal.

In five years, this is the first time I have had an issue with accidentally opening the fuel valve without knowing. Fuel flowed into the heater for a full day before I noticed the small puddle of fuel on the floor below the heater. This situation was easily remedied though, allowing me to continue using the heater without any issue.

Runaway Diesel Heater

Diesel heaters are a great way to keep your cabin nice and toasty during the winter. They provide a reliable dry heat that will keep you comfortable. Dickinson heaters are very simple and straight forward to operate, making them a heat source you can count on. As long as fuel is getting to the unit, it will burn and it will heat your cabin!

The problem is sometimes these units get a bit too much fuel and will burn way too hot for comfort. The fuel chamber will find itself too filled with diesel, causing it to burn out of control! The fuel is already past the carburetor, so shutting off the fuel flow won't do very much good. You will just have to let it burn itself out as the fuel is consumed and the fire begins to dwindle.

While the excess fuel is burning off, the unit will glow red hot and begin to rattle. This is a bit concerning and very avoidable. By simply opening the door a smidge, fresh air will enter the unit above the fuel and cause the fire to burn much less intense. The fuel will still burn, just at a much calmer rate which will make everyone inside the cabin much more relaxed as everything returns to normal. Once the fuel level has gotten back to normal, you can close the door all the way and resume using it as normal.

Starting a Dickinson Diesel Heater

Keeping warm in the winter is crucial if you are planning to live aboard comfortably. Diesel heaters are a very efficient and powerful way to heat your cabin, providing plenty of heat without the buildup of condensation typical with other types of heaters. 

The cabin air inside the yacht will be used in the combustion process, taking along with it any moisture that is present in the air. This burnt air is then sent out through the chimney, keeping the cabin free of smoke and carbon monoxide.

As the air in the cabin is consumed, new air must be brought in to replace this air. Dorade vents that are used for passive ventilation in the yacht will allow fresh and dry outside air to be drawn in and quickly warmed by the burning heater.

This is all well and good, but how do you get the thing started? If you read the instructions, you may become intimidated as the instructions are rather complicated. Actually, the instructions are overly complicated. The truth is, these heaters are remarkably easy to turn on and get started.

All you need to do is start the flow of fuel, wait a few minutes, and light it. That's it!

The video is rather long, as it is the entire process of starting the heater and watching the flame slowly come up to the top where it begins to burn efficiently and heat well. The steps taken in the beginning are the only steps you need to take to get the heater rolling! Once you carry out those steps, the rest is just a matter of waiting.