Check Your Gas Locker Drain!

[buzzstar]

Originally Posted by waltdrechsler

I just went through this on our Moody 47. Gas locker is out on the deck with the drain over the side. I opened the locker to turn on the tank and both bottles "popped" up. Locker was full of sea water from an aggressive passage. Took out the solenoid. No breakfast that morning for the grumpy skipper! I'll be checking the drain more often from now on.

Yep, the right thing to do if you use a propane system. You had turned off the source! Arguably, a PITA, but you are alive and uncharred. Thanks for the example. Propane can be OK, at least not reasonably less safe than the alternatives if the procedures are explicitly followed, including no reliance on automatic solenoids. I say this in part because I am old, but prefer not to die or suffer as a result of burns from avoidable fires.

[Dockhead]

Originally Posted by waltdrechsler

I just went through this on our Moody 47. Gas locker is out on the deck with the drain over the side. I opened the locker to turn on the tank and both bottles "popped" up. Locker was full of sea water from an aggressive passage. Took out the solenoid. No breakfast that morning for the grumpy skipper! I'll be checking the drain more often from now on.

Wow. Misery loves company.

I guess your drain is routed the same way as mine, or it probably wouldn't get clogged. Be sure to correct that so gas can get out.


EDIT: To be absolutely clear, since some people in this thread missed this point or don't understand the principle:

If you have a trap in the drain line -- any tiny spot where water can stand -- then it WON'T drain gas. Because water WILL stand there and block the gas. The gas locker drain needs a clear run downwards, more slope the better, and no place for water to stand.

[Pelagic]

Is not VENTILATION the most important part of a propane tank storage locker?
As I said before, my 2 tanks are stored under the starboard seat locker on their sides.

Typical solenoid switch from the galley and a habit of manually turning off valve at tank after each cooking period
I have vents high up to bring in air and at lowest point a drainage hole to outer deck. That is how it came

When painting in 2015, I did modify the large 3" scupper half pipe that helps to drain the open ended inside cockpit by drilling a few venturi holes so that the wind moving thru the tunnel helps to draw out air inside the locker.

(Half pipe removed for painting in this photo)
Seems to work as it stopped all mold issues I usually have during the wet monsoon season

That's why I thought ventilation was more important than drainage?

[Dockhead]

Originally Posted by Pelagic

Is not VENTILATION the most important part of a propane tank storage locker?
As I said before, my 2 tanks are stored under the starboard seat locker on their sides.

Typical solenoid switch from the galley and a habit of manually turning off valve at tank after each cooking period
I have vents high up to bring in air and at lowest point a drainage hole to outer deck. That is how it came

When painting in 2015, I did modify the large 3" scupper half pipe that helps to drain the open ended inside cockpit by drilling a few venturi holes so that the wind moving thru the tunnel helps to draw out air inside the locker.

(Half pipe removed for painting in this photo)
Seems to work as it stopped all mold issues I usually have during the wet monsoon season

That's why I thought ventilation was more important than drainage?Attachment 144913

I think drainage is more important, because propane is very heavy, 1.5x as heavy as air IIRC. It takes a long time for it to mix with air and dissipate. Obviously this will work better with some air flow, but I don't think it will happen passively.

Do I understand that your locker drains to the side decks? Where would spilled gas go from there? Is there any way for it to get blown back into ports or hatches? Normally you want gas lockers to drain through transom or topsides, not onto the deck.

[Pelagic]

Yes it does drain thru 3/4" scupper hole (no hose) on to side deck which then drops one step down to large overboard scupper at midship area.

I guess it could theoreticaly find its way to my head / shower porthole which is normally opened at anchor....
Just never thought it would migrate in such volume from outside, without us smelling it.

I'm pretty fussy about the propane connections and do soap tests on a regular basis, but as you said, the danger is in hidden run sides, inside the vessel.

[Dockhead]

Originally Posted by Pelagic

Yes it does drain thru 3/4" scupper hole (no hose) on to side deck which then drops one step down to large overboard scupper at midship area.

I guess it could theoreticaly find its way to my head / shower porthole which is normally opened at anchor....
Just never thought it would migrate in such volume from outside, without us smelling it.

I'm pretty fussy about the propane connections and do soap tests on a regular basis, but as you said, the danger is in hidden run sides, inside the vessel.

Don't count on smelling it. Most accounts of gas explosion survivors say they didn't smell anything. If it gets into your heads, it will just find its way into the bilges. You aren't even in the heads all the time.

But depending on the relative positions of all this, maybe it's unlikely enough not to worry about. You'll have to use your own judgement. Or convert to electric

ABYC says the drain has to be led through the hull:

A-1.8.5 Locker vents shall be led outboard, without
pockets, through the hull to a point lower than the locker
bottom and above the waterline with the boat in the static
floating position.

http://oya.com/yardblog/wp-content/u...11/01/A-01.pdf

[Pelagic]

I am more concerned with the more convoluted new copper piping from tanks to galley.
With the new chest freezer/fridge I had to rerun underneath into the blige and back up to stove.

Pipe was sweated on to heated reinforced hose before running to protect it, but too many turns for my comfort level.

I may just go electric inside and keep the propane tanks for the BBQ

[stillbuilding]

Originally Posted by hafa

One sailboat that visited our island recently had their tanks mounted on the (quite solid) stern rails. This seemed to me to be one method to ensure that gas could not collect in an enclosed space.

I have had two 6 kg stainless steel tanks mounted on the stern rails. Was actually difficult to get approved in the 80's cos it wasn't an approved arrangement !! Looked ok and worked well. Had a gas shut off solenoid which used to get the nervous nellies and stop the cooker from working at the most inopportune moments ( like when we just caught a really nice fish).

Just one more reason not to use LPG.

[Dockhead]

Originally Posted by Pelagic

I am more concerned with the more convoluted new copper piping from tanks to galley.
With the new chest freezer/fridge I had to rerun underneath into the blige and back up to stove.

Pipe was sweated on to heated reinforced hose before running to protect it, but too many turns for my comfort level.

I may just go electric inside and keep the propane tanks for the BBQ

I would also be concerned about that.

I think electric may be a good plan.

[DeepFrz]

Pelagi, could you explain that bit about ventilation holes into an inside locker. Did I read that right? If so then that is a real no no with LPG.

[Pelagic]

Hi Deep Friz,
The propane locker(cockpit seat locker)




is above the steel weather decks and no penetrations inside.
The ventilation surrounds the seat storage locker to keep the inside mould free

[DeepFrz]

Oh, okay. Thanks. Sorry for misspelling your name.

[Pelagic]

That's OK...I like Italian ! [emoji1]

[buzzstar]

Interesting, I my opinion. I spoke to one of my sons lat night. He lives in Malaysia, in Kuala Lumpur, in a typical high rise, with his two kids. It so happened, his gas had run out, and he was waiting for the gas man to install a new "container" A little questioning indicated the gas is used only for cooking (the rest of the appliances and the AC are electric) and the "bottle" is located under the sink, next to the stove/oven (the only appliance it powers). To me this sounds less safe than the installations and usage on most boats. Oh well, it is beyond my control, and to the extent there is a choice, it is his.

[Pelagic]

Buzzstar....that is exactly my experience renting apartments in Manila.

Their screw in connector for bottles come with rubber O-ring and are hand tightened.

I guess they expect them not to leak and you can smell the smallest escape of gas....so we are much fussier for boats.