Shore power

I have been emailing back and forth with Bob about this subject. I want to clear a few things up

I am in no way telling anyone to be half ass when working with propane or natural gas at home for that matter. It can kill you quick if you are stupid or even lazy but so can electricity. Hell I am more scared of electricity then most things. If you understand how it works, what the dangers are, and take the safety precautions then propane can be our friend. Is easy to use and allows you to not be hooked up to a dock and dependent on others for power.

Now with all that said I dont have a propane heater on my boat. I have a diesel heater, as does Bob. Its a better choice for me and my use.

So if you have a propane heater, a oxygen sensor ( which will not detect a propane leak but propane will displace oxygen and set off the sensor), a thermocouple equipped heating unit ( hard to find one with out these days) with a tilt sensor then you would have to work fairly hard to harm your self. For the stated use at the beginning of this thread its hard to beat really.

http://www.mrheater.com/ProductFamily.aspx?catid=41

I would use one of these in a c-dory with the widow or hatch open and the door ajar a inch any time. With a detector installed. but hey thats just me.
 
FWIW,

We have a 100' bright yellow 10-gauge 15A (its packaging indicated 20A) shore power cord. It takes about the same space and weight as our 50' 30A cord, which we no longer carry. We often need the 100' length (and fairly often wish we had more) at Auke Bay in Juneau, where there are power supplies only at float intersections. 15A has always been enough for us - charging 12V batteries at 50A (at most, less most of the time) takes less than 6A at 110V, and we can at the same time run an electric heater or water heater.

We have a pigtail 30->15 adapter on the boat end, and when necessary a maybe 5" long cylindrical plastic 15->30 adapter on the dock end. Despite the rain, the adapter at the dock end doesn't seem to need wrapping - it's usually protected somewhat by the design of the pedestal. Even though I'm sure it has been very wet more than a few times, it has had no resulting problem.

We don't seem to need zipties - just wind the cord around the power pedestal, and loosely around a cleat on the boat. With 100' length, we can usually lay the cord out of the way of walkers, and run it up overhead to cross the float at a float intersection.

All this gear is 15 years old, has been used many times, and still looks good - guess I ought to inspect it very carefully once in a while.
 
Depends on how many dogs you have! We always have a one dog night in the C Dory--she knows right where to get--and then works her way up...

Digging around during Tom and my discussions in PM I came on an interesting comment--which seems to be factual. Oxygen sensors and shut off systems cost more than the Mr. Buddy heater does. It turns out that:
There is no O2 sensor and the safety shut off is undeniably simple. When O2 levels lower there is a cooresponding shrinkage in the size of the pilot flame. When the flame shrinks down to a certain level, the thermocouple(temperature sensitive switch) deactivates, shutting off the fuel supply to the heater. Not enough O2 = no fuel to burn.

I would not depend of the "oxygen sensor" to shut off the heater in case of a propane leak--for several reasons...especcially the way the O2 sensor "works".
 
interesting. I take it that comes from the mr heater web site. Well if you are worrying that the small tank will leak while the unit is on, don't. Any leak that reaches the open flame with only flash burn back to the leak source and then snuff out. The bottle will not explode, this is not hollywood. Even a room full of propane will not explode unless there is enough air. Propane, despite popular belief and hollywood, will not burn all by itself. It has to have the right amount of air. Not to much and not to little.

I walked into a basement with a propane leak at the hot water heater. The propane leaked and filled the low floor until the gas reached the pilot light on a gas dryer ( new gas dryers are electric light). Then it would burn back to the leak and snuff out at the hose. In 10 mins. it would do it again.

As I have said before a separate oxygen detector ( or lack there of) in the cabin is always a good idea.
 
Since we're discussing various thoughts on heat and power, which can have dangers/cautions associated with them.... one of my "things" isn't that the danger does or doesn't exist, but rather that a person using the various devices understands the risks (and then can presumably act accordingly).

For example, I have talked to several people who are afraid of propane, but carry butane stoves aboard, and even keep the cartridges in the cabin, or where they could drain into the cabin. When I mentioned this (as compared to a propane installation with a proper locker, a few safety features, etc.), they said "Oh, but butane rises so it's not dangerous like propane." My understanding is that this is false, and butane sinks just like propane (CNG does rise, but is not usually in the running due to difficulty finding fills). But what got me wasn't the properties of either one, but the fact that the choices/risks were being made due to misunderstanding or misinformation.

Sunbeam

PS: There may be more, but the one difference between propane and butane that I know of is that butane will quit working properly at low temperatures that will not faze propane.
 
don't tell bob but I have started small fires under large (500 gallon) propane tanks in the winter to get them to work. It was so cold on a mt top that the propane in the tank would not vaporizer. You do not burn the liquid form of propane. You burn the vaporized gas of propane as it reaches its boiling point AND has room to do so, a out let for the propane. We had to get the propane to that boiling point (-43 degrees f). I would have shoveled the snow off and painted a black spot on the tank, another trick that works, but it was dark still. and remember to be careful.
 
starcrafttom":3eqztkxa said:
We had to get the propane to that boiling point (-43 degrees f).
Click to expand...

Yikes!

I've only used propane down to around -36ºF or so; I guess I was lucky it didn't get any colder! Note: Not living in such a cold place anymore :mrgreen:
 
Sunbeam is correct that propane and butane are heavier than air (1.5 propane, 2.0 Butane). Natural gas is 0.6 to 0.7, lighter than air. But Natural gas cannot be easily compressed to a liquid as LPG, Butane and Propane can, so that a bottle of Compressed Natural gas will not last as long as any of the other gasses. This is why it has not taken off as a marine stove fuel (I lived aboard a boat with CNG in the early 70's).

As for Tom's comments--you don't know what the concentration of a leaking gas is in any one specific area. Tell that a leaking canister of propane will not explode when exposed to air and an open flame to my close friend who had 30% of 3rd degree body burn from just that scenario--3 months in ICU, 2 months in a coma and over a month on dialysis.

I need to point out that "A room full of propane" is dangerous to a human's health. Again OSHA has rules about propane exposure, and the PEL is 1000 PPM. Short time exposure over 100,000 can have immediate effects.

No one has stated or inferred that a cylinder of gas will explode from leaking, but the gas can either burn or explode when mixed with air.

As for propane explosion ratio there is a specific air to gas ratio. For propane they are 2.2% (lower explosive limit) and 9.5% (upper explosive limit). Pray tell how you know that a gas is below or above those limits? You cannot without expensive meters (see below) I can say that you were a very lucky man that you were not injured walking into a basement with leaking propane leak, if it filled the Low floor until reaching the pilot light.

As for "oxygen detector"--I do not know of any recreational boat oxygen detector--nor any reason to have one. The cheapest industrial single gas oxygen detector meter is about $200. Professional grade industrial gas meters I used when working as OSHA supervisor at a university was about $2500. Perhaps Tom meant LP detector (explosive gas) or CO detector?

If using a built in LP gas system, I feel it is essential to have a Propane detector or "sniffer".
 
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