Heating options for Cape Dory 27 Sailboat

[Atcowboy]

I've been thinking of getting a cabin heater for my CD27 and have been casually looking since I pulled my boat in early November.

In that casual research, what I discovered is there are A LOT of different options for cabin heaters. Enough that I feel overwhelmed.

One system that had caught my eye was the Wallas stove, a diesel stove that can be equipped with a flip-lid that vents the stovetop heat with a small fan. Closing the stop top (like a laptop) converts it to heater mode, where a thermostat controls the temperature output of the stove. It seems like a really great solution for the very small interior space of a 27', and also removes the open-flame hazard of the alcohol stove there currently. Unfortunately, it seems like the price for these has not only gone up but the American distributor seems to be out of stock.

The other heaters I have found have been what I'll term "torpedo" heaters that get hidden somewhere in the boat, with exhaust and heated air vented through hoses. These are also prolific in the van life scene, with some China knock-offs at $140. Most seem to be diesel, but there must be propane flavors also. The problem I see with these is the space taken away from storage, as well as routing the exhaust. I've read that the cabin heat from these can be very hot (200*F) so even the wanted hot air seems like it would take nearly as much care as the exhaust.

The last type of heater I've seen are I guess what I'll call "stoves". Something that gets mounted on a table or against a wall, and the body heats the cabin directly (or at least there is no duct work). These would be like a Dickenson or Sig style. Fuel options are the most prolific here, diesel, kerosene, stove oil, wood. It also seems like most of these do not require any electricity, which on a simple sailing vessel is always a bonus. The problem I see with these is the space they will consume in the cabin/living space. Realistically, the only place I can imagine one of these living in my boat is where the table is mounted on the wall. This means no table, though, and effectively the loss of a berth.

I am assuming that people have tackled this problem dozens of times over before me, so I'm hoping I could get some first hand information about how it has been done and if you are happy with the results.

Cheers,
-AT
1979 CD27 Cailín

[Rob S.]

I'm going through the same process.

I'm 90% of the way to deciding on the 'torpedo' approach, i.e. an Espar D5. It can fit in the very aft section in an area inconvenient for storage. It will take fuel directly from the main diesel tank. A single 4" duct hose will carry warm air to the saloon. I don't care about heating the sleeping cabins; blankets will do. It is very fuel efficient as well as 12V system efficient. Some vents will have to be installed to allow the system to breathe. It promises to provide on-demand heat very quickly. We will see.

There is a hydronic option which circulates heated water through pex tubes to heat exchangers at various points, but seems to demand much more power and fuel, and I'm trying to stay energy self sufficient so that is a no for me.

I was very tempted by a compact wood stove, but I don't want to give up the cabin space, I've heard they can be very messy, and I don't really want to deal with a chimney on the deck.

The diesel and other heat radiating options seem plentiful but then you are dealing with some of: auxiliary fuel tanks, fuel pumps, multiple fuel types, and overflow tanks. And you still have to give up cabin space. It is nice to be 12V free, though, and some have glass panes to to see the flame which is cozy. Here is a link to a nice one that has great videos for installation:

https://refleks-olieovne.dk/en/produkter/

On my old boat (CS30) I may have been willing to give up the port mini - berth to make room for such a stove, but in the current one I am not.

The stovetop units are tempting but I have my doubts they could adequately heat my saloon.

My two cents!

Also there are some other good threads in here with great info that you may have already seen. But probably this new thread will generate some more good info!

[psk125]

This sort of idea came up in another thread where the OP wanted to live aboard in Alaska. The best suggestion he got was to determine what the volume of the cabin was and what heat input would be needed in BTU's to keep it at a reasonable temperature. This had to factor in what the outside temperature might be, along with the fact that the water the boat sits in conducts heat away from a source twenty five times faster than air. The guy in Alaska found out he needed double what he thought. Calculate how many BTU's you need and THEN look for a stove that will satisfy that need. Then hope you can fit it somewhere.

[manitu]

Liveaboard, daysailer or weekender?
Need hot water?
Need heat at night?
Minimum outside temperature?

Then you might get a better answer.

.manitu

[Atcowboy]

Originally Posted by manitu

Liveaboard, daysailer or weekender?
Need hot water?
Need heat at night?
Minimum outside temperature?

Then you might get a better answer.

.manitu

I intend to liveaboard.

If hot water was a byproduct of cabin heat I would look at the pros/cons. But my boat is hand pump only, don't know if I want the added complexity.

I definitely want the heater to be able to run over night.

Ideally it wont be hard pressed temperature wise, I'll move the boat to warmer climes. Taking the chill off spring and fall evenings and such. But having just been in Florida and waking up to frost, at least 32*F. Water temperature warmer than that though.

I just went through a pretty bad week after ETA rolled over Block Island. Freezing temperatures, sleet and hail on deck. After a couple days of suffering in dripping cold misery, I was gifted a 1500W electric ceramic heater and the use of a 30AMP cord. This was enough to keep the boat pretty warm - I was able to sit around in my shorts watching Netflix waiting out the storm. I could choose the V birth to be warm or the saloon.

Electric Heater; 1500W = 5119 BTU
Wallas DT Stove; 850W to 1900W = 2900BTU to 9861BTU (2,000BTU to 6650BTU according to website)
Chinese Furnace; 5000W = 10,236BTU

Based on the electric heater being able to warm one room or the other, I figured both the stove and the furnace at about twice the output would allow me to warm the whole boat as long as I had some fans to move the heat around.

- AT

[Atcowboy]

Originally Posted by psk125

This sort of idea came up in another thread where the OP wanted to live aboard in Alaska. The best suggestion he got was to determine what the volume of the cabin was and what heat input would be needed in BTU's to keep it at a reasonable temperature. This had to factor in what the outside temperature might be, along with the fact that the water the boat sits in conducts heat away from a source twenty five times faster than air. The guy in Alaska found out he needed double what he thought. Calculate how many BTU's you need and THEN look for a stove that will satisfy that need. Then hope you can fit it somewhere.

How did that Alaskan calculate his heating needs? I haven't seen his thread. I can only ever find "if it's this big" (and in regards to houses!). Nothing useful like calculating heat loss.

- AT

[rphdiego]

I have installed 3 of the Chinese diesel 'parking' heaters. Although they are around $125 on ebay the proper installation materials for a marine application add up to about $350. Still much cheaper than a German Espar.

[SV__Grace]

Originally Posted by Atcowboy

I intend to liveaboard.

Ideally it wont be hard pressed temperature wise, I'll move the boat to warmer climes. Taking the chill off spring and fall evenings and such. But having just been in Florida and waking up to frost, at least 32*F. Water temperature warmer than that though.

I just went through a pretty bad week after ETA rolled over Block Island. Freezing temperatures, sleet and hail on deck. After a couple days of suffering in dripping cold misery, I was gifted a 1500W electric ceramic heater and the use of a 30AMP cord. This was enough to keep the boat pretty warm - I was able to sit around in my shorts watching Netflix waiting out the storm. I could choose the V birth to be warm or the saloon.

Electric Heater; 1500W = 5119 BTU
Wallas DT Stove; 850W to 1900W = 2900BTU to 9861BTU (2,000BTU to 6650BTU according to website)
Chinese Furnace; 5000W = 10,236BTU

Based on the electric heater being able to warm one room or the other, I figured both the stove and the furnace at about twice the output would allow me to warm the whole boat as long as I had some fans to move the heat around.

- AT

Liveaboard at a dock with access to power, or live aboard at anchor?

We have hydronic, but it's noisy and uses diesel AND power,
though not excessive, we installed a Dickinson and we're happier with that as we live at anchor 99% of the time.

If you're moving to a warmer climate wouldn't your electric AC heater do until then?

[Cheechako]

I have some input, albeit maybe not solutions:
-A free standing kerosene burner type didn't heat a cabin well at all in a 30 ft boat.
-A large free standing diesel heater was very problematic, dirty exhaust and smelly. Would crank out some good heat after it burned for a couple of hours. Best to leave it on continually.
-A free standing propane burner type was no better than the kerosene unit, but easy to light.
-A bulkhead mount forced air unit worked quite well once I used kerosene in lieu of diesel. It was a Japanese Toyoset unit.
-A small Wallas worked very well. They dont have to be put in a cabinet and ducted like so many people do. You can KISS, just bulkhead mount and let it blow! I believe some are available at reasonable cost like truckers use.

The problem on boats is it can be hot at the ceiling and your feet can be freezing. Forced air units help correct this. Bulkhead mount blowing right under the table works great!

[TrentePieds]

Rob S.:

The below decks "living space" in a CD27 will measure out to just about 700CuFt. As it happens, that is what the Reflex 665MW is claimed to be able to heat. Going full bore, that beast is said to require 1/3 litre of diesel fuel per hour, which equates to 8 litres per 24 hours, or roughly 2 gallons per 24 hours.

However. heating the 700 CuFt to room temperature requires that the hull be insulated, tho' I don't know to what "R" value. Furthermore, the constant opening and closing of the hatch that is inevitable in a CD27 (as it is in TrentePieds) will drastically reduce the interior temperature in the living spaces. You simply cannot heat a small boat as if it were a house. Here at 49ºN , where you and I both sail, I find that suitable clothing is a far better bet than artificial heating, but being constantly swaddled, night and day, is something most landsmen have to grow used to. My beloved and I routinely sleep aboard down to the sort of temperature of a coupla degrees of frost that we see on the southern end of Vancouver Island. Yes, it a tad shivery getting out of the sleeping bag first thing in the morning, but once the first pot of coffee has been made, the propane cook stove has usually brought the temperature at the dinette up to 52 or 55 degrees - perfectly livable! But that is, of course, as long as we don't open the hatch :-)!

TrentePieds, a raised saloon sloop, has rather more space below than a CD27. Even so, I see no place in TP where I can justify putting a bulkhead mounted heater. You do NOT want a heater mounted where you can get burned if you accidentally touch it, and you do not want a heater mounted where it can be dislodged by a man being thrown against it in a seaway!

For my money, therefore, it would have to be what you call a "torpedo heater". In TP such a thing could find room in the engine compartment and vent at the bottom of the access hatch directly into the saloon.

I understand that the CD27 has a 13 gallon fuel tank. Therefore the tankage, assuming no engine use, would be enuff for six days or so if the above cited heater were run continuously at full output.

So I advise you to do your numbers before you commit to an installation.

All the best :-)

TrentePieds

[Nord Sal]

A bulkhead-mount Dickinson or Refleks is fairly compact and might fill the bill. You won't get the oven that the stove versions have, but you'll still get a small surface to make hot water or coffee. You'll have plenty of heat, I just don't know how well it would fit. Mount it (it any heat source) as low as possible in your cabin.

I've been more than comfortable in a Tee shirt inside while it's been 10°F outside with my diesel stove. I never turn the carburetor setting past "5" and typically have it on "3" the hottest setting is "9." These number correspond to the fuel usage in cc/min per the manufacture.

These stoves run well for long periods. They are not suited to be run for short periods of time to "warm up." I know fisherman running theirs 24/7 through the winter months.

If it takes two hours to heat up and is sooty and problematic as others mention, it wasn't installed properly or was malfunctioning somehow. While you will likely see a little sooty smoke from your flue for a few minutes after initially lighting it, they burn cleanly once warmed up.

If you use a day tank to gravity feed the heater, you can have dry warm heat without consuming any electricity.

[Atcowboy]

Originally Posted by SV__Grace

Liveaboard at a dock with access to power, or live aboard at anchor?

We have hydronic, but it's noisy and uses diesel AND power,
though not excessive, we installed a Dickinson and we're happier with that as we live at anchor 99% of the time.

If you're moving to a warmer climate wouldn't your electric AC heater do until then?

Liveaboard wherever I want, or can, or what feels safe. Anchor is nice because it's free of course. The system should ultimately be well rounded though.

My AC distribution system/heating is a 30amp cord finagled through the crack in the companion way hatch with a 15amp adapter, haha. I don't want to need shore power for heat.

- AT

[Atcowboy]

Originally Posted by SV__Grace

Liveaboard at a dock with access to power, or live aboard at anchor?

We have hydronic, but it's noisy and uses diesel AND power,
though not excessive, we installed a Dickinson and we're happier with that as we live at anchor 99% of the time.

If you're moving to a warmer climate wouldn't your electric AC heater do until then?

In my brain, the boat moves north and south to follow the heat and escape the scary spiny things that flatten homes and destroy boats. My sharing of the Florida experience (which was while living in the back of my Jeep, not on a boat) was just to say that even in warm parts of the US one can wake up to weather you'd rather have a heater for. Especially since it gets so damn wet inside the boat (Jeep too!)!

How big is your boat, and your Dickinson? What do you use to move the heat around?

- AT

[Atcowboy]

Originally Posted by TrentePieds

Rob S.:

The below decks "living space" in a CD27 will measure out to just about 700CuFt. As it happens, that is what the Reflex 665MW is claimed to be able to heat. Going full bore, that beast is said to require 1/3 litre of diesel fuel per hour, which equates to 8 litres per 24 hours, or roughly 2 gallons per 24 hours.

However. heating the 700 CuFt to room temperature requires that the hull be insulated, tho' I don't know to what "R" value. Furthermore, the constant opening and closing of the hatch that is inevitable in a CD27 (as it is in TrentePieds) will drastically reduce the interior temperature in the living spaces. You simply cannot heat a small boat as if it were a house. Here at 49ºN , where you and I both sail, I find that suitable clothing is a far better bet than artificial heating, but being constantly swaddled, night and day, is something most landsmen have to grow used to. My beloved and I routinely sleep aboard down to the sort of temperature of a coupla degrees of frost that we see on the southern end of Vancouver Island. Yes, it a tad shivery getting out of the sleeping bag first thing in the morning, but once the first pot of coffee has been made, the propane cook stove has usually brought the temperature at the dinette up to 52 or 55 degrees - perfectly livable! But that is, of course, as long as we don't open the hatch :-)!

TrentePieds, a raised saloon sloop, has rather more space below than a CD27. Even so, I see no place in TP where I can justify putting a bulkhead mounted heater. You do NOT want a heater mounted where you can get burned if you accidentally touch it, and you do not want a heater mounted where it can be dislodged by a man being thrown against it in a seaway!

For my money, therefore, it would have to be what you call a "torpedo heater". In TP such a thing could find room in the engine compartment and vent at the bottom of the access hatch directly into the saloon.

I understand that the CD27 has a 13 gallon fuel tank. Therefore the tankage, assuming no engine use, would be enuff for six days or so if the above cited heater were run continuously at full output.

So I advise you to do your numbers before you commit to an installation.

All the best :-)

TrentePieds

Most of my sailing is around the 41st parallel.

Experiencing first hand how quickly living in a 40* cabin, with water raining from every condensable surface, even my synthetic layers wet and clammy, toes and fingers not quite cold enough to be numb with cold, instead cold enough so I get to experience the exquisite pain of it, experiencing how quickly that life made me want to scuttle the boat and fly home. When I was changing out of only damp clothes to put on wet clothes to go outside and check for chafe or take the dogs for a walk, over and over again, slowly coveting what "dry" clothes I had left because eventually those damp clothes will also be wet clothes... well that just wasn't my idea of fun. My unrealistic dream of cruising is to bask in 80* heat all the time. It made me promise myself to get a heater.

Temperatures where I have to put pants, heaven forbid a shirt or foot prisons, are really problematic for me. You see I'm a nudist at heart, so wearing shorts is a legal compromise for me.

All kidding aside, with the help of people in this thread I feel I am leaning towards a parking (torpedo) heater. 5kW, so I have some head room if I end up hanging around New England in the fall. I feel pretty confident I can find room for the unit without much sacrifice in space. I don't envy the extra complexity it will add to the boat, but they do seem fairly simple.

- AT

[Sailmonkey]

With the “torpedo” heater, be sure you’ve got a way to cover the electrical demands. No point having a heater if you’ve got dead batteries in the middle of the night.