General advice for cabin heat in northern lattitudes

[Jammer]

Help me understand the tradeoffs and what is practical.

- Solid fuel stoves
- Diesel pot burners e.g. Sig, Newport
- Newport propane "fireplace"
- Fan-forced diesel systems Eberspaecher/Webasto
- Hydronic

Reading about the problems people have with these systems, I am largely inclined to believe that a solid fuel stove is the best choice (having grown up in a house with wood heat). Someone please talk some sense into me.

[robert sailor]

Your choice for heat will be influenced by the size of your boat and the outside temperatures in your area during winter and how much time you are spending aboard. Smaller boats, under 40 feet that are used on weekends can often be heated with solid fuels..means you have to carry wood or coal but short term probably not a big deal. You'll need good fans to drive the warm air down and cycling throughout the boat or your feet will always be cold.
A drip pot heater is usually a better alternative as it means you can draw your fuel from an existing tank and it can run full time day and night(which most of these heaters like) the heaters can be purchased with larger heat capacities than most small solid burners. There is an art to installing and operating these heaters and it's not as simple as a wood burner but I have personally used them for years and I've had trouble with everyone of them but over time solved the problems and was very satisfied with the results. Again somewhat limited in boat size depending on outside temps.
I'm not a fan of propane heaters, especially bulkhead types. They use a lot of fuel and don't produce heat like a kerosene or diesel heater. You are making steady runs to refill your propane tanks...I'll put a caveat on these and say they are fine for occasional use for weekenders but not a great option for live a boards.
Finally the diesel forced air heaters or the same system using a hot water system from a diesel fired boiler. I've owned and used both. The hot air system is cheaper to buy and install and is the fastest way to heat a cold boat. These units do cost more to buy and maintain but if you have the money they are very comfortable to live with because it's controlled by a thermostat just like most homes. They do use up the amps which won't be a consideration at the dock but if your anchored out it's something you should consider.
The hot water system is probably the Cadillac system as instead of running large aluminum ducts throughout the boat and using up storage space they simply run small diameter waterline. This means that every outlet can be individually adjusted for heat, say cooler sleeping areas and warmer living areas. The other big product of the system is that it supplies a constant hot water system to the boat.
So 2 big factors when choosing a heating system, price and effectiveness...depends on your budget

[Mike OReilly]

I’m going through the same process myself Jammer. I love the idea of a wood stove; something like this: https://cubicminiwoodstoves.com/coll...ini-wood-stove
. Our last house heated with wood. I always loved it, and miss it. The benefits are many: simple installation, relatively cheap, no cost for fuel, and plenty of fuel available everywhere.

The reasons I haven’t are the soot issues on deck, keeping the wood storage and down-below areas clean, plus the challenge of having a large enough dedicated carrying space for the wood.

[Mike OReilly]

Originally Posted by robert sailor

...A drip pot heater is usually a better alternative as it means you can draw your fuel from an existing tank and it can run full time day and night(which most of these heaters like) the heaters can be purchased with larger heat capacities than most small solid burners. There is an art to installing and operating these heaters and it's not as simple as a wood burner but I have personally used them for years and I've had trouble with everyone of them but over time solved the problems and was very satisfied with the results. Again somewhat limited in boat size depending on outside temps.

When you say “drip pot” I assume you mean something with its own tank? Like this one:
https://ca.binnacle.com/product_info...oducts_id=8391

Can you tell us more about the challenges of installing and operating one Robert? I’m leaning towards something like the linked one. I would love to install a forced air diesel system, but the cost is prohibative now that I’m officially poor.

[Dockhead]

Originally Posted by Mike OReilly

When you say “drip pot” I assume you mean something with its own tank? Like this one:
https://ca.binnacle.com/product_info...oducts_id=8391

Can you tell us more about the challenges of installing and operating one Robert? I’m leaning towards something like the linked one. I would love to install a forced air diesel system, but the cost is prohibative now that I’m officially poor.

No, he means a pot heater -- Dickinsen, Sigmar, etc. A passive drip diesel heater.

[Mike OReilly]

Originally Posted by Dockhead

No, he means a pot heater -- Dickinsen, Sigmar, etc. A passive drip diesel heater.

So, this is different than being gravity fed DH? What does gravity fed mean then? And how does the pot heater get its fuel?

I’m not trying to be a PITA. I really have no experience with this stuff.

Maybe I’ll just stick with my Origo burner

ADD: Found a Sigmar heater: https://www.elyboatchandlers.com/wal...-diesel-heater

It talks about being gravity fed. Is this a “pot heater”?

[toddster8]

Regardless of heat source, I think the biggest heating issue with most boats is utter lack of insulation. You'd think a modest amount of BTUs would heat a small cabin, but the only boats I've been on that were really toasty warm had big old diesel galley stoves that threw out massive heat. After a few teeth-chattering nights, I extended the foam V-berth cushions all the way up the top sides. Makes a cozy little nest, but there is still massive heat-loss through the deck overhead. There seems to be a half-inch or so gap between the liner and the deck, and I've considered trying to inject some kind of spray foam into there - I don't know how to make it flow evenly and fill the space without gaps though. From the snow-melt patterns, it looks like the biggest heat-loss is through the ventilators (no surprise) and the companionway. There was something in Good Old Boat last month about building heat exchangers for ventilation and added exterior insulation, but that only seemed applicable to permanently docked boats.

FWIW, I sold the (uninstalled) solid-fuel heater that came with my boat and put in propane. I spend enough time dealing with wood stoves at home all winter, and the thought of carrying FOUR kinds of fuel on a little sailboat just seemed stupid.

[sailorchic34]

Originally Posted by Mike OReilly

So, this is different than being gravity fed DH? What does gravity fed mean then? And how does the pot heater get its fuel?

I’m not trying to be a PITA. I really have no experience with this stuff.

Maybe I’ll just stick with my Origo burner

ADD: Found a Sigmar heater: https://www.elyboatchandlers.com/wal...-diesel-heater

It talks about being gravity fed. Is this a “pot heater”?

Yes it's a type diesel pot heater, fed with a gravity tank. You can also use a diesel pot heater with diesel from the boats fuel tank with an electric fuel pump. A gravity tank heater has the benefit of not needing power to heat the boat.

[Dockhead]

This question has been thoroughly covered on this forum, and you will find a lot of good information in the archives.

I don’t mind, however, summarizing the information which is available.
There are different opinions, so you should read up and make up your own mind, but I’ll give you mine. Starting with fuel:

1. Solid fuel – how are you going to carry all that fuel? Sourcing AND CARRYING a separate type of fuel – do you mind the hassle? Where will you store it on board? Think about getting rid of ashes. Soot on deck from the stack. No accident that solid fuel is pretty rarely used on modern boats.

2. Propane – more expensive than diesel, harder to source and carry. Big plus: totally clean burning so no maintenance on the burners. But in my opinion fatal flaw: cannot be used safely inside the boat, and is actually prohibited by ABYC. So you would need to set it up somewhere outside the main hull volume – do you have any place in your boat? I don’t.

3. That leaves diesel fuel. Fuel the heater from your main tank, so no different kind of fuel to buy. No transportation necessary; you already have the storage. Minor disadvantage is that burning it is not entirely clean, so burners etc. need some maintenance. But all in all – heating with diesel is really a no-brainer in my opinion.

That is outside of a marina. If you are on shore power, then electric, but you will want some non-electric heat source for anchored, under way, in ports without electric service, and in case the electric service goes down in your marina.

Now, types of diesel heaters. You have:

1. Pot heaters (Sigmar, Dickenson, etc). An excellent choice with big advantage that they require no electrical power and are dead simple and reliable – all maintenance easily done yourself. Disadvantages: poor distribution of heat (can be mitigated somewhat with fans and some people put a water coil in them for radiators and/or calorifier loops, but that starts to get complicated). Also you have to have a stack through the deck, and you get some soot on deck and in sails (but less than with solid fuel). Another disadvantage is mounting – need to find some bulkhead space or some other place to put it.

2. Truck heater (Eberspacher, Espar, Webasto, Planar, etc.), air-based. Relatively cheap and easy to install, much easier to find a place for than a pot heater. Blows hot air and you can connect more than one outlet via ducts if you want. Simpler than hydronic. No stack – exhaust is blown out the forced air burner through a pipe let into the transom or topsides. Also a great choice. Drawback is they need professional maintenance fairly often so costs something to keep them up and very hard to maintain and repair yourself.

3. Hydronic heater (Eberspacher, Espar, Webasto, Planar, etc.). More expensive because you have a whole hydronic part to install. Advantage compared to air-based truck heaters – you can distribute heat far and wide very efficiently via skinny and easy to run water pipes, rather than ducts. So this is preferable for larger boats. But another big advantage is that these will make your domestic hot water via a coil in your calorifier. Drawbacks – same as air-based truck heater. Advantages – all the same.

So there you have it. You pays your money and you makes your choice. I have hydronic on my boat, but my next boat – which I intend to use in very remote places – will definitely have a pot heater in addition to a hydronic heater.

It’s also worth mentioning reverse cycle AC as heat – what I used on my last boat. If you have decent water temperature, and you have a source of electrical power (shore power, generator), this is fantastic heat, very efficient. Not a substitute for diesel heat if you’re going to be in cold water or need heat which doesn’t require a lot of electrical power, but a great thing to have. You get it more or less for free if you anyway have air conditioning (I don’t on this boat).

[nwdiver]

I found the problem with a small solid burner (a Scandinavian Ulufos) on a 35 foot well insulated steel boat was, it was too hot most of the time, I ended up converting the space to a dickenson diesel cook stove the smallest one that was used during the winter. It supplied heat, cooking and hot water, it was a gravity fed pot burner.

The difference between gravity fed and pump fed pot burners it the placement of the fuel tank, the easy way use gravity is from a 2-3 gal day tank........

[Dockhead]

Originally Posted by Mike OReilly

So, this is different than being gravity fed DH? What does gravity fed mean then? And how does the pot heater get its fuel?

I’m not trying to be a PITA. I really have no experience with this stuff.

Maybe I’ll just stick with my Origo burner

ADD: Found a Sigmar heater: https://www.elyboatchandlers.com/wal...-diesel-heater

It talks about being gravity fed. Is this a “pot heater”?

Yes -- the fuel drips into the "pot", where it burns. But you don't need a gravity tank necessarily -- as Sailor Chic mentioned, you can feed it with a fuel pump. But inside the heater, the fuel is simply passively dripped onto the fire, as opposed to being sprayed into a combustion chamber with a force draft burner. It's much simpler and requires no electrical power.

[nwdiver]

Originally Posted by Dockhead

Yes -- the fuel drips into the "pot", where it burns. But you don't need a gravity tank necessarily -- as Sailor Chic mentioned, you can feed it with a fuel pump. But inside the heater, the fuel is simply passively dripped onto the fire, as opposed to being sprayed into a combustion chamber with a force draft burner. It's much simpler and requires no electrical power.

The little pulse feed pump needs a tiny bit of electricity......

[CarlF]

For many, the deciding factor is the chimney. It has to pierce the deck in the main cabin with a large hole, have good draft, not interfere with running rigging, and be well insulated from the surrounding deck structure to not set anything afire. On some boats, this is easy. On others quite difficult.

The Hamilton Marine catalog (in Maine people know something about boat heat), give a sense of the installation challenge.

https://www.hamiltonmarine.com/catalogs/00308.html

[conachair]

Originally Posted by Mike OReilly

So, this is different than being gravity fed DH? What does gravity fed mean then? And how does the pot heater get its fuel?

I’m not trying to be a PITA. I really have no experience with this stuff.

Maybe I’ll just stick with my Origo burner

ADD: Found a Sigmar heater: https://www.elyboatchandlers.com/wal...-diesel-heater

It talks about being gravity fed. Is this a “pot heater”?

Drip feed, gravity fed, diesel pot - I've always assumed they're the same thing but an often wrong

I have a refeks and like it very much. Just this moment lit it, a little bit of meths to get it going though it can be lit with a good hot gas match .

This one on a 10m steel boat so not bad insulation.
https://refleks-olieovne.dk/71m-ms/

There's a little header tank in the heads, some valves divert the pump from the main tank to either the header tank or the engine day tank. The reflks has a regulator that feeds the tiny amount needed to keep it going, often leave it on when on passage if it's cold and the boat not heeled right over, so nice getting warm down below again and keeping the boat dry.

With the chimney low I ended up putting a little computer fan on the air intake to help it to burn clean, will burn for days at a time now, clean decks.

On a bigger boat you'd probably need to think about some way to get the heat around the boat otherwise it works great, nothing nicer than to be snug and warm down below when its wet and windy and freezing outside, with a nice stew on hotplate on the refleks

[Mike OReilly]

Thanks DH, SC, nwdiver. I was just trying to confirm the lingo here, and that I was indeed looking at the type Robert referenced. I understand a pot burner can be fed by a pump or simple gravity. I’d still love to hear about the challenges you’ve gone through with these Robert.

DH, I agree with you on the fuel thoughts. Although I love the idea of a wood stove, I just can’t see it making sense. And propane seems highly problematic, and appears to be not very efficient. This makes diesel the obvious choice.

Like I said, I’ve looked at the Espar-style forced air options. I’d love to have one, but the cheapest I could find were in the multi boat-buck range. And as you point out DH, they seem to require a higher level of maintenance than I could easily do myself, so up-keep costs appear to be high. In contrast, these simple diesel drip heaters look fairly inexpensive, and easier to maintain. But here again, I’d love to hear Robert’s experiences.

toddster8, you’re no doubt correct about the benefits of insulation. On my current boat, I’ve only ever heated with a simple alcohol Origio burner, and it keeps us comfortably warm, and I’m used to cruising in what most people consider cold areas. I have no additional insulation, but my boat’s decks and cabin are quite thick, and the hull is partially cored. I wonder if this provides enough insulation…?