Unpressurized fresh water system?

[cluttonfred]

I am kicking around ideas for low-cost boat systems and now thinking about water. Attached is a diagram of a typical 12v fresh water system. Obviously, plenty of boats have hand pumps and/or small gravity fed tanks and do just fine, but I would like a hot shower and don't want to rely on a solar bag shower.

I really only need hot water for the shower, and if I want hot water for another purpose I can always fill a bucket from the shower. So I think I could get away with 12v pump --> tankless propane water heater --> shower head. No other plumbing, just a 12v switch for shower on or off. The temperature would be pre-set at the water heater. The result is just like one of those camping shower systems, though I'd probably use a basic submersible marine galley pump since the heater I have in mind is only intended for 1.5 gal/min flow. The rest of the boat would use hand pumps for cold water only or possibly another one of those basic 12v submersible pumps in the galley for convenience and to provide a back up to the shower pump.

https://www.eccotemp.com/eccotemp-l5...-water-heater/
https://www.whalepumps.com/marine/pr...c-Galley-Pumps

Thoughts? Any obvious pitfalls I am missing?

Cheers,

Matthew

[swoody126]

https://duckworks.com/shower-head-and-valve-handle/

attach to a black garden sprayer and leave the tank on deck for heating during the day

sw

[cluttonfred]

Thanks, but like I said I am looking for something more than a solar shower. What I described is basically this but with different components for the pump and a normal bathroom hand shower.

https://www.eccotemp.com/eccotemp-l5...-and-strainer/

https://duckworks.com/shower-head-and-valve-handle/

attach to a black garden sprayer and leave the tank on deck for heating during the day

sw

[Ian McColgin]

Since 1981 I have been using a plastic garder sprayer like this.



I took that wand off and let the water flow solidly from the end in little bursts. I eventually added a bike inner tube valve to the tank so I could use a foot pump to keep the pressure. Heat water on the stove to comfort. Pour in tank. Take your shower where ever. And even when I had hair down to my belt there was a bit left over from a 1 gallon shower.

[lupussonic]

IMG_2069.jpg

VICTORIAN BOILER.jpg

This is mine.

[amish rob]

IMG_2069.jpg

VICTORIAN BOILER.jpg

This is mine.

Gorgeous!

[lupussonic]

Thanks, Rob... The TMV valve was a game changer.

If you search for 'Kate LK126' on this forum you will find it on about page 4. I really must get back and finish her.

[amish rob]

Thanks, Rob... The TMV valve was a game changer.

If you search for 'Kate LK126' on this forum you will find it on about page 4. I really must get back and finish her.

Oh, I’m well familiar with your love. Quit working and get back to it!

[Hugh MacD]

There are lots of little propane camping units on the market, too. https://www.youtube.com/watch?reload=9&v=tEOSBSXAHXY

[cluttonfred]

This is mine.

Very cool! Is that all custom made or was the boiler something available off the shelf?

[Woxbox]

Looks workable. My only question is how big is the water tank? An electric pump on a shower can dry up a typical boat water supply rather quickly. I've seen foot pumps advocated simply because they force the user to use only what's needed.

FYI, for the galley I've found the foot pump far superior to the hand operated pump, and being low to the sole they tend to prime readily, too. I like the Whale Gusher. (No, I don't sell any of this stuff.)

[lupussonic]

Very cool! Is that all custom made or was the boiler something available off the shelf?

Ebay spécial, I have searched and searched for what it could be. It has some machined crimps in the cylinder, implying machinery and high production runs, yet also has original hand soldered fittings. I really do not know what it's original market was, but now and again I find similar in a curio shop or as decoration in a restaurant etc.

[lupussonic]

Mathew, why not put the stem shut off valve directly after the cold water tank?

[hawkeye54]

Ebay spécial, I have searched and searched for what it could be. It has some machined crimps in the cylinder, implying machinery and high production runs, yet also has original hand soldered fittings. I really do not know what it's original market was, but now and again I find similar in a curio shop or as decoration in a restaurant etc.

Looks as though it could be an old fire extinguisher, suitably modified.



Rick

[cluttonfred]

I hear you on the 12v pump and water use, but I don't think a foot pump would work for this sort of shower setup. The self-contained camping hot water system I have been looking at max out at less than 2 gal/min and can be set to about 1 gal/min. They can also be easily switched on and off during the shower to conserve water and gas so I think I can live with that.

[Hwyl]

A propane on demand unit would be dangerous on a boat. The temptation would be to leave it on, thus having the propane run possibly into the bilge.

[Arlc]

This system, with the inner fire chamber is a rocket mass heat that off-gridders use to heat their homes. I built one one those to heat a greenhouse. The theory is the combustion is hot enough so the only exhaust is H2O and CO2. The problem is without complete combustion CO is produced and leaks into the living space.

[cluttonfred]

Propane has been used safely in boats for many years, seems a bit silly to immediately predict catastrophe at the thought of it. My idea here was to have two 20 lb propane bottles (one connected, one reserve) and the on-demand heater in a ventilated locker on deck. There would be an additional propane line to a stove in the galley with a remote solenoid valve in the locker, open only when the stove is in use.

[lupussonic]

Never heard of a ventilated on demand propane heater on deck.

Automatic anything is risky, particularly pilot flames, gas and the windy sea. If I used propane I would turn it on, heat a tank up, turn it off.

What size boat is this? Inboard engine? Wood stove? Diesel heater? Tell us more about the boat and what your intended use of it is.

My gut says your plumbing is mostly fine, but the adding btu's to water may need some finessing.

[Etdbob]

Man, you guys call these simple systems?

Since '98 my wife and I have used a simple "solar shower" every day -
It hangs from a rope through a pulley over my tub.

SAM_4336.jpg

Our wood stove sits just "outside" the bathroom, and always has two big pots on it for hot water.
The shower bag is taken down and put in the sink, upside down, which holds it perfectly for filling with warm water.
In the summer I'll use our propane stove to heat the water, or even an outdoor propane burner (that I usually use for melting lead for bullets) to keep from heating up the cottage.

SAM_6592.jpg

The whole end of the "bathroom" is open of course, it's always best to have maximum ventilation in a steamy bathroom, and the big curtain which forms the "door" (which we usually leave open anyway) is certainly the cheapest way to go, easy to swap out for a change of decor, and in a boat, would be lightest and least in the way.

Yes, that's a porta potty. Our primary sewage disposal mechanism is of course the out house. The potty is for the wife for midnight convenience. The cottage has drain lines, but no running water. Our water supply in the cottage is two five gallon buckets. I joke that we do have "running" water. When we run out, I grab a bucket, run and get more! These days life is pretty soft, we had a well drilled. A solar powered pump pushes water up a hill whenever the sun shines and fills a cistern, which gravity feeds to the homestead. I have two frost free hydrants, one near the barn for the animals, and one in the kitchen garden for the humans. Neither my wife nor myself have ever felt the need to plumb it into the cottage.

I can even quote my family doctor who once remarked to us - "Running water is overrated". He'd rather folks get off their butts and do some chores now and then!

Ya know, I'm always blown away by what some folk consider necessary, and how much they will complicate maters for not having to say, open a gallon jug of water for a drink. The simplest solution's are always the best, especially for low cost cottages and cruising boats.

[cluttonfred]

Thanks, all, for the feedback. All of this is notional, exploring ideas for a freighter-like small liveaboard inspired by Tom MacNaughton’s Hero 33 concept. The size is about the same as a 20’ ISO shipping container plus engine room, bow, and pilot house. See also http://forum.woodenboat.com/showthre...aboard-systems

[Chris249]

. The simplest solution's are always the best, especially for low cost cottages and cruising boats.

Sven Yrvind's solution (no heating at all, no porta potti) must therefore be better than yours. :-) And the guy who rides long cycling tours without using complications like toothpaste or deodorant must have more fun than the wimps who like to sleep on something more than bubble wrap, as well.

The cyclist says that licking off your own sweat is simpler than carrying washing gear, so it's better. So if simpler = better, why do you need a shower at all?

[cluttonfred]

Quick question from someone who's never built or owned a boat more than 16' long...when you have a fresh water system using manual and/or 12v submersible pumps, how do handle the connections to the tank and the filler? Are folks using bulkhead fittings or draw tubes to allow the tank to stay sealed but for a high vent, so you can just fill the tank and any overflow comes out the filler? Or are the draw hoses and/or submersible pump just dropped in the top of the tank, but then you can't use a deck fill because it would overflow in the boat? Thanks in advance, Matthew

[Ian McColgin]

Whether foot or electric powered, you use in-line diaphragm pumps. On most cruising boats you'll hear a gentle put-put-put when water is being used. So, the pump is outside the tank. On Meg the tanks are under the settees in the saloon so the bottoms of the tanks are at cabin sole level. It is usual to locate the pumps to minimize lift, but sometimes when the tank is especially low some lift is required. For example, many glass or metal cruising boats have a tank built into a hollow keel above the ballast.

[cluttonfred]

Thanks, but my question really concerns the tank set up. Do you pull the water from an outlet low down on the tank, or from the top, and if the latter, how do you set up the tank with a submersible pump like this one?

https://www.whalepumps.com/marine/pr...c-Galley-Pumps

[Woxbox]

This is the more common type of pump, which Ian referenced. On the boats I've had, there's a fill on deck or in the cockpit that's well above the top of the tank. A line from the bottom of the tank runs to the pump. The vent is also high up, exactly where depends on the boat. Or alternately, a bladder tank is used which doesn't need a vent. I don't see that putting a submersible pump inside the tank would require any other changes.

[Ian McColgin]

I know of no boats with submersable pumps in their tanks. The reason is obvious, unless you have a perfect pump that never fails.

Many water tanks indeed have the outlet low on the side. Being of a cautious cast, Meg's water tanks were built like fuel tanks, outlet pipe down from the top. And of course tanks set deep in the bilges will perforce have the outlet through the top.

[David Satter]

This is in my 1973 Bristol 30 , you only need 2 or 3 gallons for a shower. This has worked great for years. Dave IMG_4714.jpg

[cluttonfred]

That's a neat idea considering I was only focusing on hot water for the shower, thanks.

[David Satter]

That's all I needed to keep the family happy. very simple. My handheld in the head even had a hose long enough to pass out through the portlight if you wanted to stand on the deck. If you look close you can see the blue cap in the counter top behind the heater. I hid the tank under there. 100_1028.jpg
Simplicity afloat is the surest guarantee of happiness. LF Herreshoff