Reptile Smile
Well-Known Member
Post 54 above you?
Very small boat heating
- Thread starter ghostlymoron
- Start date
Fantasie 19
Well-Known Member
Reptile Smile
Well-Known Member
Thought you were talking about crediting Dylan, rather than generic flowerpots...
lw395
Well-Known Member
Generators are noisy in an anchorage.
And usually worse aboard.
Would I want to sit on a small boat for the evening with a generator running? No thanks!
Those that aren't properly installed have a poor record regarding CO2, to put it mildly.
700W is not nearly enough. Not used just for an hour or 3.
Boating being what it is, stuff gets damp. You want either long term background heat, like a 500w heater running all evening and overnight, or a couple of kW to get things warm and dry quickly.
Because you need airflow to take the damp away, you need more heat than you think.
It's like heating a car when you get in it after walking in the rain. You want lots of heat and the fan cranked up and probably a window open a bit.
A VW polo is smaller inside than the boats we are talking about, and their heaters are quite a few kW.
Momac
Well-Known Member
Someone did suggest a hot water bottle and get some warm clothing which may be on the right track.
A Thermos flask may help to retain a hot drink while avoiding a need to open a hatch for air supply for a gas hob.
Other possibilities may include re-usable gel heat pad hand warmers .
If a heater that uses a flame is decided as a solution there must first be a carbon monoxide alarm.
A Thermos flask may help to retain a hot drink while avoiding a need to open a hatch for air supply for a gas hob.
Other possibilities may include re-usable gel heat pad hand warmers .
If a heater that uses a flame is decided as a solution there must first be a carbon monoxide alarm.
ghostlymoron
Well-Known Member
Lots of interesting ideas. Cosy woodburners, hi tech eberspacher, physics defying night lights. Comments so far, anything needing mains power would require an extension lead approximately half a mile long (assuming that the nearest householder would let me plug in), blown air or drip feed would necessitate a diesel fuel tank (I presently have only a plastic 5 gal outboard tank). I'm going to try the Tilley lamp which has several advantages - the main being that I already have one in the garage. The noise and excessive brightness may interfere with listening to the radio.
Seajet
...
So how come there's yet another plea for help by an Eberspacher owner running right now then ?!
Heating and ventilation on boats is always a balancing act, very much like a thermal version of plate spinning.
ghostlymoron
Well-Known Member
"So how come there's yet another plea for help by an Eberspacher owner running right now then ?! "
And how many eber owners are eating their breakfast aboard their boats wearing just their pyjamas? And not bothering to tell us?
And how many eber owners are eating their breakfast aboard their boats wearing just their pyjamas? And not bothering to tell us?
PaulRainbow
Well-Known Member
Yeah, i see that. Lack of maintenance, allowing the filter to block.
Be like people with Origos complaining how unreliable they are, because if you don't put fuel in them they stop working.
I've had to turn mine down very low, it's too hot in here
Dave95979
Active Member
I use chafing gel fuel tins in the little holders you can get to control the heat the can be pricey but if you can get them cheep
lw395
Well-Known Member
You don't get anything for nothing.
Personally I can't stand the smell of parafin and oil lamps and so forth, or the inevitable MAB effect of running such things in a confined space. I think that's why hardcore sailor used to smoke pipes, to cover up that smell?
I'd rather go for the thermals, a duvet and an open hatch.
Except I can recall a particularly miserable early summer cruise when it drizzled nearly all week. Small boat, no heating, no sprayhood. No time flexibility to give up and go next week instead.
It's the damp that gets you.
Worse as you get older.
I'm considering the minimum spec for my next boat. and that memory is one thing that makes a Eberbasto a 'must have'. That plus the desire to get a longer season for my ££££.
I think that means an inboard for charging, but I'm open to persuasion that solar or some sort of really quiet buit in generator, or a wind gen or something else might be viable.
PaulRainbow
Well-Known Member
You'll need to things, adequate fuel supply, i use 40 litres a week if it's on constant, and enough panels. Mine draws about 2a.
lw395
Well-Known Member
I had one on a previous boat, I never ran it for more than a few hours a day. So the fuel tank does not worry me.
The electrical needs are more of an issue. Places I am likely to go, how much will I really get from solar panels? Let's say late season up the River Dart or Fal. A few dull days between steep wooded banks in November? Plus there will obviously be other electrics needed, like lighting.
sarabande
Well-Known Member
I am going to risk the wrath of the diesel fuelled warm air heaters...
GM's boat to be heated is small. I doubt whether the main cabin volume (judging by my daughter's 20ftr) is much bigger than a MPV. There is no overwhelming need for heated air in such a cabin, and the surface area/volume ratio is much smaller than bigger boats.
In turn that means the people inside are much closer to a heat source than on a bigger boat, so radiant heat is significantly more effective.
Night storage heaters use bricks made of magnetite which absorbs heat (being metallic) in large quantities.
If GM made a steel box to contain a number (2, 3, 4) of these bricks, and put it on a stove either in the cabin or in the cockpit, the bricks will absorb heat from the gas/spirit stove until they are almost red hot. This will take some time.
GM than takes the box with the hot bricks, places it carefully on the cabin floor, and sits back enjoying lots of radiant heat and also some hot air (similar to the forum). The bricks will stay hot for a long time.
While in use, the bricks do not give out carbon dioxide, carbon monoxide, carbon nanoparticles (like candles do), and can be re-used almost ad infinitum.
Hot bricks (or rather cold hot bricks) can be stored out of the way until needed, do not need a licence, maintenance, insurance, or a training course, and as such as ideally suited to the small boat sailor. (When I say small, that is not an aspersion on GM's size. For all I know he may be 7 ft tall but agile) )
I commend hot bricks to the house.
GM's boat to be heated is small. I doubt whether the main cabin volume (judging by my daughter's 20ftr) is much bigger than a MPV. There is no overwhelming need for heated air in such a cabin, and the surface area/volume ratio is much smaller than bigger boats.
In turn that means the people inside are much closer to a heat source than on a bigger boat, so radiant heat is significantly more effective.
Night storage heaters use bricks made of magnetite which absorbs heat (being metallic) in large quantities.
If GM made a steel box to contain a number (2, 3, 4) of these bricks, and put it on a stove either in the cabin or in the cockpit, the bricks will absorb heat from the gas/spirit stove until they are almost red hot. This will take some time.
GM than takes the box with the hot bricks, places it carefully on the cabin floor, and sits back enjoying lots of radiant heat and also some hot air (similar to the forum). The bricks will stay hot for a long time.
While in use, the bricks do not give out carbon dioxide, carbon monoxide, carbon nanoparticles (like candles do), and can be re-used almost ad infinitum.
Hot bricks (or rather cold hot bricks) can be stored out of the way until needed, do not need a licence, maintenance, insurance, or a training course, and as such as ideally suited to the small boat sailor. (When I say small, that is not an aspersion on GM's size. For all I know he may be 7 ft tall but agile) )
I commend hot bricks to the house.
PaulRainbow
Well-Known Member
It's complicated, but best bet IMO is to work out what you'll need and fit as much solar as you have room for. LED lights use a tiny amount of power, i have some converted 8w tube lights, fitted with 15 LEDs and they use just .3 amps per fitting.
lw395
Well-Known Member
The specific heat capacity of magnetite is 0.67 j/K/g
So, let's say 10kg of bricks, heated to 200degC.
That would be 1273kJ or 0.35kWh.
So you would need a lot of bricks and get them very hot.
How do you efficiently heat bricks to hundreds of degC efficiently in a boat?
The obvious answer is you have them lining a cast iron stove.
It could be the way to go for a narrowboat (with care re CO from the embers etc), not so sure for a small sailing boat.
Water on the other hand has a specific heat capacity of 4.2 so 10kg of water would only need to be heated to around 40degC to hold the same heat.
Of course a Yanmar does this as a side effect. As does a calorifier.
I get it's not radiant heat, it's low level background heat that is good for drying stuff and general comfort.
You are right, radiant heat is nicer. Think hot sun on a cold day, or roaring fire in pub. That's back to needing some serious hundreds of degC though.
One of these:
https://www.safariquip.co.uk/all-ca...o-kettles/ghillie-adventurer-15-litre-kettle/
1.5 litre of volcano kettle.
Does a cafetierre and a couple of hot water bottles?
JumbleDuck
Well-Known Member
The damp fug of catalytic gas heaters was dreadful too. Yeugh.
JumbleDuck
Well-Known Member
A pedant writes ... surface area to volume ratio scales as L2/L3 = 1/L and therefore increases as a boat decreases in size.
However, I agree with you that a sophisticated heating system is unnecessary on such a small boat. Something to give a quick blast of heat is nice, but otherwise warm clothes should do fine.
sarabande
Well-Known Member
I know what I meant to say and that's what you said I was trying to make the point that a bit of radiant heat in a small boat is more effective than in a big boat and it's easier for crew to be warmed by proximity.
And if night storage blocks are NFG for storing heat, then why not use a lump of steel such as a bar bell weight. Toasty
I was trying to make the point that a bit of radiant heat in a small boat is more effective than in a big boat and it's easier for crew to be warmed by proximity.And if night storage blocks are NFG for storing heat, then why not use a lump of steel such as a bar bell weight. Toasty
JumbleDuck
Well-Known Member
I know what I meant to say and that's what you said
Smaller boats have a larger surface area to lose heat, but they also have less dead space inside to warm up ... the second outweighs the first, I think.