Hot water on demand?

[belizesailor]

Originally Posted by hellosailor

...

Most of us take, or took, propane for granted. How could anything that is stocked and sold in every corner hardware store be dangerous?

...

One visit to a burn ward can give you religion about combustible gasses.

Or one experience with a propane explosion. Knew a cruiser who died that way...absolutely demolished his entire boat...he took several days to die in a burn unit...not on my top 10 list.

[Mr B]

I lived in a caravan on site for four years while building my house,
I was on the phone one night while waiting for my dinner to cook in the stove,

The flame went out, Big deal, So with out thinking, I leaned over and went to light the stove up again,
As I was lighting the match, I realised what I was doing and threw myself backwards,
The flame came out and went up the side of my body singing all the hairs on my arm, half my beard went and half the hair on my head,
Yes, I was very lucky, A few more minutes with the gas on and flowing into all the crooks and crannys,
I wouldnt have had a caravan, Possibly very badly burnt or dead,
Its totally Illegal to carry any flammable gas inside any vehicle, Boat, Etc Etc here unless it is totally vented to the outside,

The law changed after a few vans with gas leaks exploded, and all that was left was the badly bent floor and wheels hanging of it, The owners were very dead,
Leaking gas inside is worse than having petrol leaking inside, Its a much bigger and more violent explosion,
And you dont get a second chance with it,

I drove a literal bomb for 30 years, Mobile welder, It had petrol, Diesel, Propane, Acetylene, on it,
It was all exposed to the weather and air, So it all blew away, I made sure there were no leaks in any of it at all times,
But a still day with no air circulation, You could still smell the fumes,

[smj]

This is our setup. We probably burn 10-20 times more propane cooking on the stove than we do on the water heater. Why is it so much more dangerous. And just look at all that wood to burn!

[Celestialsailor]

Originally Posted by Cheechako

The problem with ABYC is they don't think outside the box. There is no difference in using a flow thru water heater like the L5 than there is using your propane cookstove. If you use it as an "On when in operation and off when not" device like the stove. ABYC is unable to understand that type of thought process.

Yup...I have an L5 I bought off Amazon for $99., new. I built a chimney manifold fo it and is vented outside. Works great but occasionally blows out with a strong breeze. It has a thermal coupler that shuts the gas off in that event.

[Paul L]

It's not like there haven't been deaths caused by propane hw heaters on boats. This is an old article, for sure:
2 accidents prompt boat-heater probe Woman killed, 2nd injured by noxious fumes. - tribunedigital-baltimoresun

[crabcake]

Originally Posted by sailorchic34

and one I believe makes perfect sense to an engineer who thinks belts and suspenders is not overkill.

"How can you trust a man who wears both a belt and suspenders? The man can't even trust his own pants."

Frank (Henry Fonda), Once Upon a Time in the West

[Dirk Williams]

Agree that propane explosions are a problem. I've been to dozens of propane related explosions, fires, and sadly deaths. I live above 4200 ft, in the mountains

My boat is only 33.5 long, for the era, it's well set up, I just don't have the room many of you have. My freeboard, is very low, and I'm 11 ft wide.

I'm just someone who likes things neat and tidy. I'd really like to mount the L5 in the head, for practical application. This is the first propane utility feature I have on the boat. My stove is alcohol. I've done a fair amount of cooking on alcohol stoves,,and don't mind the extra time required. Alcohol is easy to source, around the world, non gasses and a little goes along way. No oven.

I question just how much propane out of a 1 poumd Coleman bottle. Is that amount of gas really explosive, in a 33 door open floor planned boat.

So I've decided on the following I'm going to mount the L5 in the head on the forward bulkhead. I'll use one pound bottles, screwing them on and then off after hot water application.

Then store the 1/2 used bottle on deck. Likely in PVC as suggested.

The consequence of the bottle on/ off is a structured plan or order with which daily hot water use is conducted. IE, dishes first, then shower, then secure the 1 pound bottle on the cockpit.

I really like the ease of routing the L5 exhaust into the required composting toilet vent. The hole for the composting toilet exhaust already exists, in the cabin roof. Factory install.

In researching the composting toilets, the info I've reviewed is roughly 60/40 regarding gases emitted from the toilet. I think it prudent to err on the side of caution.

60 percent say no gas. 40 percent say yes, some gas, " how would that gas amount be measured?"

I view the install of the toilet, and the L5 water heater as the same project, a day project, fairly,straight forward. The water storage is roughly two feet aft, centered, from the head. A " PEX plastic " line to the L5, and then PEX plastic back down, thru the bilge, aft into the galley sink. The head sink will remain cold water.

Although I'm not the op, thank,you,for helping me work thru the potential issues. I think a very realistic plan for me, has developed out of all your input.

Thank,you.

Dirk

[Pete7]

Originally Posted by hellosailor

"1lb. bottles that I stored in my ABYC compliant locker for a year ..... they are empty "

We went to change over a camping gaz cylinder last summer only to find the new spare cylinder empty. It had leaked. Thankfully it was kept in a gas locker which vented over the side of the hull, otherwise 2.7kgs of butane inside the boat would have been an accident waiting to happen.

Pete

[Cheechako]

Originally Posted by Pete7

We went to change over a camping gaz cylinder last summer only to find the new spare cylinder empty. It had leaked. Thankfully it was kept in a gas locker which vented over the side of the hull, otherwise 2.7kgs of butane inside the boat would have been an accident waiting to happen.

Pete

Yep, they often leak. Found a few new ones empty myself. (not in the boat!)

[Dockhead]

Originally Posted by Dirk Williams

. . .I question just how much propane out of a 1 poumd Coleman bottle. Is that amount of gas really explosive, in a 33 door open floor planned boat.
. . .

1 pound (440g) of propane has more than 20 megajoules of energy, or about the same as 4.4kg of TNT. One stick of dynamite has about 1 megajoule of energy in it. Just about the right amount of power to blow you and your boat into tiny bits.

At the risk of repeating myself and others -- your plan is not a good one.

[Cheechako]

I don't see the L5 use as an issue. I do see the use of small cannisters inside as an issue. Taking them on and off to avoid leaving them on the L5 just risks more leakage on a cheap valve design. The hot water heater doesn't need to be in the head at all. Find a good convenient place for it and run water hose to the head.

[accomplice]

Add my voice to those advising *against* this type of installation.

Its your life, though. Please, though, if you live to sell the boat, please tell any potential buyer about this dangerous situation before selling them the boat. Also, if you cannot bring yourself to follow ABYC, at least install a propane sniffer and improve your odds.



Sent from my SM-G930V using Cruisers Sailing Forum mobile app

[uncle stinkybob]

Originally Posted by Dockhead

Just remember.that natural gas in a house is lighter than air and disperses easily. And houses don't have bilges, so has safety even with LPG is fairly trivial, compared to the situation on a boat.


Sent from my D6633 using Cruisers Sailing Forum mobile app

Not true, basements. In 1971 a restaurant my dad was part owner of exploded, caused by natural gas leak in the basement. A neighboring hotel was also destroyed in the blast. A refer unit switching on caused ignition. 38 injured. A house the same year I believe exploded injuring 1.

https://www.google.com/url?sa=t&rct=...yv8YD_HOHQnNYg

[ReMetau]

We are currently on our second Excel ventless tank less propane heater. The last one last about 4 or 5 years, and eventually just wouldn't ignite.

We have it installed in the anchor locker on a dedicated 10 lp propane system with a water solenoid which is only open when the propane is on. Works fantastic. Have been using it as liveavoards and cruises for years without problems. We both shower on board about every other day most times. The 10lb tank lasts about 6 months.

Now I use the space taken up by the old water heater for batteries and stowage.

[smj]

I know all but one on demand water heater doesn't meet ABYC standards, but what about other boat building standards? Do they meet standards in Europe or Australia? I still can't see much difference between running a well vented stove or a well vented propane water heater.