Onboard Heat for Northern Climes

[jeanathon]

Does anyone have recommendations for a temporary heat source? I will be moving a boat soon in the cold, and have been wondering what I could use to safely heat the boat for a couple of weeks.

[Nessus]

Originally Posted by DeepFrz

Nonsense...diesel heaters, cook stoves and ovens are all vented outside, at least every one that I have seen. They put out as dry a heat as any coal or wood stove. Most of the humidity in a boat comes from propane stoves (cooking), showers and us. And it is probably us that puts the most humidity into the inside of a boat.

Well after this comment, I can tell you for a fact; you have not seen every type of stove.

[Nessus]

Originally Posted by Surrymark

In all of these useful answers, there is only one mentioning a propane heater. Are they generally considered just too - what?.

Propane while very clean releases the most amount of moisture. When it's cold and very humid outside (which is often the case on an ocean); propane won't allow you to thoroughly dry out. Not that it won't keep you warm; it will. Many forced air heaters are propane which are dry when properly vented.

[captain58sailin]

I have not had any moisture issues with a diesel stove, been using them nigh on 45 years, keep the boat dry and toasty, I cannot speak for all diesel stoves, just the ones I've used. Propane, is a wet heat and will cause condensation, unless both the intake and exhaust is vented to the outside, there, then where ever the exhaust is mounted there will be water run off. If I had the room for the fuel, I would use a wood stove, just isn't practical for me.

[Nessus]

Originally Posted by captain58sailin

If I had the room for the fuel, I would use a wood stove, just isn't practical for me.

Same here. I love wood and coal, it's just not practical for all situations.

[Surrymark]

Originally Posted by Nessus

Propane while very clean releases the most amount of moisture. When it's cold and very humid outside (which is often the case on an ocean); propane won't allow you to thoroughly dry out. Not that it won't keep you warm; it will. Many forced air heaters are propane which are dry when properly vented.

The Dickinson Newport is vented to the outside and, if I understand it correctly, also draws its combustion air from the outside, apparently through a double wall flue. This could mean that it is not drawing (and therefore expelling) moist interior air, but it also means that cabin air is not being depleted. The heat should be as dry as forced air, no? The Cozy Cabin (formerly Force 10) seems to use a very small flue, but uses cabin air for combustion. Question is, do people find the propane fuel impractical? Or is there some other reason why so few people are mentioning propane for heating? I'm talking about coastal cruising in the US where, within a week or so, it should be possible to refill. For a month or so on blue water diesel seems most practical, or a hundred pounds of charcoal or wood pellets.

[Nessus]

Originally Posted by Surrymark

The Dickinson Newport is vented to the outside and, if I understand it correctly, also draws its combustion air from the outside, apparently through a double wall flue. This could mean that it is not drawing (and therefore expelling) moist interior air, but it also means that cabin air is not being depleted. The heat should be as dry as forced air, no? The Cozy Cabin (formerly Force 10) seems to use a very small flue, but uses cabin air for combustion. Question is, do people find the propane fuel impractical? Or is there some other reason why so few people are mentioning propane for heating?

It's not unusable. Many boats heat with propane. The humidity is not going to sink your boat while you're sleeping or anything. Most folks just get up whenever it starts raining in the cabin, and turn the heater off lol.

[onestepcsy37]

jeanathon - i've no experience north of 45 degrees, but i've had to endure some cold evenings at anchor in north florida. we used a small propane heater powered by single one pound bottles. kept below our dining table in the evening and near the berth at night it warmed us just enough to take the chill off.

worked satisfactorily but i wouldn't recommend it for long term cold cruising - too much of a pain to use. one pound bottles can be expensive but can be refilled using a 20 dollar adapter and a full size 20 pound lpg tank; then it costs less than one dollar per bottle.

this one has a low oxygen shutoff and a tipover shutoff. about 60 dollars. cheaper than a real built in heater.

Mr. Heater® Little Buddy® Indoor Infrared Propane Heater (F215100) - Heaters - Ace Hardware

[DeepFrz]

Nessus, perhaps you could give me an example of a diesel heater that is not exhausted to the outside. For my own edification.

[Nessus]

Originally Posted by DeepFrz

Nessus, perhaps you could give me an example of a diesel heater that is not exhausted to the outside. For my own edification.

I worked a season on the Mystic Whaler out of Mystic CT. The galley was equipped with a dripped diesel stove. It was an ornery stinky bastard and I managed to flood the galley sole with diesel one morning when the stove failed to light. One of my fellow crew owned a vintage Hinckley also equipped with a drip stove for heat and cooking.

Mystic Whaler. 85' on deck and four of us slammed in the focsle. Loved every minute.

[DeepFrz]

The galley was equipped with a dripped diesel stove. It was an ornery stinky bastard and I managed to flood the galley sole with diesel one morning when the stove failed to light.

Dripped diesel stove doesn't mean it wasn't vented outside. Did it have a stovepipe? If so then it was vented externally.

[Nessus]

Originally Posted by DeepFrz

Dripped diesel stove doesn't mean it wasn't vented outside. Did it have a stovepipe? If so then it was vented externally.

Oh it had a stove pipe and it was vented. Did it matter aboard the Hinckley?; no.

EDIT
My experience aboard that Hinckley was in it's slip aboard in february for a few weekends. It was frigid in CT and that stove went non stop.

[Dockhead]

Originally Posted by Nessus

It's not unusable. Many boats heat with propane. The humidity is not going to sink your boat while you're sleeping or anything. Most folks just get up whenever it starts raining in the cabin, and turn the heater off lol.

Propane heaters, unlike diesel or solid fuel heaters, are usually vented right into the cabin. So the heater depletes oxygen and puts out combustion products into the air you breath. Nasty. Besides that, propane has more hydrogen than most other fuels, so produces a lot of water in the combustion products. Double nasty. On top of all of that, propane is quite dangerous inside the cabin because it is heavier than air and so if spilled, will sink into the bilges, turning your boat into a bomb. Need I go on?

Whatever you use to heat your boat, vent it to the outside!

Any fuel, properly vented, including propane, will not add moisture to the cabin.

[Trekka]

I have a bulkhead mounted Force 10 propane heater that vents outside but draws air from inside. Also have a 3 burner stove and oven which is not externally vented. (I have two 20lb propane tanks with an A/B switch). I have never had condensation problems from using these. I like to use the oven for baking and thereby as a heat source along with the heater. Now, they are not my only heaters. Dockside I also use 2 electric space heaters, one of them a ceramic and the other the West/Caframo.

FWIW my boat has a very thick hull and deck. That may be why condensation is not the same problem I had on my previous boat with the typical GRP thinness.

[cal40john]

Originally Posted by Nessus

It's not unusable. Many boats heat with propane. The humidity is not going to sink your boat while you're sleeping or anything. Most folks just get up whenever it starts raining in the cabin, and turn the heater off lol.

If the combustion gas is vented outside it does not add humidity. The Newport he is talking about is vented outside. A Mr. Heater is not vented and will increase humidity.

http://www.northerntool.com/shop/tools/product_200395499_200395499?cm_mmc=Google-pla-_-Heaters-_-Propane-_-173690&ci_sku=173690&ci_gpa=pla&ci_kw={keyword}&gc lid=CICYpZ_5m7QCFWrZQgodSUYA9g

If you use cabin air for combustion you will dry out the boat more as you will cause outside air which is cold and therefore has less water in it to enter the cabin. As that air heats up its relative humidity decreases.

You can't use cabin air for combustion anymore as everybody now knows this always causes instant death. (snide remark in case anyone missed it)

John