Introduction

What is really the best way to heat a boat or RV in the colder months. It’s a common enough question here in Northern England. Here is a range of possible answers for you.

There are a number of alternatives when you want to heat a boat or RV in preperation for the colder months. These include propulsion fuels like diesel and petrol, gas, electricity and solid fuels like wood or coal and its derivatives. On our boat, we have several of these alternatives to hand. The best way to heat a boat or RV is your choice, and that I hope that this article helps you in that choice. The following methods of heating are random, favouring none. I’m ignoring heaters that involve fuels like petrol.

Diesel heaters.

Tend to be highly favoured on boats and almost univerally used by RV’ers, campers and commercial vehicles. With the exception of boats the diesel heaters used are air blown types. There are many manufacturers of these heaters, but many will recognise Eberspacher and Webasto as two of the earlier major suppliers. Some, including the two makers mentioned, offered heated water versions that will heat radiators and provide hot water for domestic uses like washing and showering. The Hydronic unit shown above incorporates a circulating pump and thermostat. A friend of mine has this one and he heats his 50 foot narrowboat with it. It does a really good job. His is the 5kw version.

The image above is a water heater type. My friend has the 5kw version and it is extremely effective in his 50 foot narrowboat. It runs all the radiators and heats the calorifier for usable hot water. For him, this is the best way to heat a boat or RV.

Over recent years, many more makers have come onto the scene. I am not reviewing these newcomers, but would hope that future buyers would look carefully at the reviews of products they are thinking of buying. Frankly, some of the ‘cheap as chips’ offerings are simply, not fit for purpose. Mutton dressed as lamb in fact.

Diesel can also be used in oil burner fires, some of which have heat exchanges to provide hot water too. They can make a focal point in a boats cabin and add a little ‘atmosphere’.

Electricity

When it comes to pure convenience, or spot heating, electricity heating is a winner. Of  course, unless you’re on a very large cruiser with massive battery capacity it’ll be no good to you. If however, you’re on a boat that’s moored with mains connected – or an RV with a hook up, electricity is very convenient. Convecter heaters and fan heaters are the basic but oil filled radiators are also very common. For some, this could be the best way to heat a boat or RV.

Given the massive rise in the cost of fuel oil, electric does seem so expensive in comparison. Where I’m based the average price of marina supplied electricity by meter averages about 23 pence per kilowatt hour (January 2025) which I think is very reasonable.

Gas

It’s unfortunate that some of our local gas bottle suppliers appear to be having a laugh at their customers expense. Bottled gas is ridiculously expensive. Okay, whinge over.
A lot of gas is still being used for cooking, and maybe to a small extent for heating too in some recreational vehicles, but I don’t think it is the best way to heat a boat or RV. Cost is one reason and the other has got to be safety concerns. Gas users that only use it for cooking may like to read another article on this site that shows a way to completely remove gas for your boat or RV.

Solid Fuel

I’ll put my hand up here to admit that, in my opinion, I am very biased towards solid fuel fires as a very eficient source of heat and hot water. I believe, for my own reasons, that the best way to heat a boat or RV is solid fuel. I hasten to add that right now, on this marina, a friend of mine has fitted a tiny solid fuel stove to his motorhome- and it works really well!

The beauty of this type of stove is that it will also burn wood, giving you a choice of possibly free fuel. As it is we use the smokeless re-formed ovals. Typically, in this last winter we burned an average of 50 kgs of fuel a week, costing less than £30 a bag. The stove has a heat exchanger, which I made myself, that is connected to radiators around the boat. I fitted a zone valve in the water line and thermostat, so that when the water reaches a temperature of 42 degrees celsius it automatically opens the zone valve to send heat to the hot water tank.

A Little tip if you have a solid fuel stove

Here’s a little something that may help anyone with a solid fuel stove that gets a bit too hot, or you want to slow the burning down overnight. This works well with the reformed smokeless ovals. The pictures below show a standard, old garden hoe. I cut the handle down to about 50 cms, about 20 inches. If I want the fire to last all night I’ll put more ovals onto the back of the fire and use the hoe to push the whole fire backwards. This has the effect of reducing the air gaps in the fuel. Trust me, it really does work!

 

You might like to read this article on Wikipedia that gives general ideas about heating, insulation and ventilation.