Any ideas about how i can add hot water?

[Kaptain Ken]

Sometimes the simplest solutions are the best (and less costly). On my first boat, a Catalina 27, we carried two black "solar shower bags". I think I've seen them at both Defender and West Marine.

https://www.defender.com/product3.js...274&id=3345684

This was the least expensive at Defender ($8.99). Most are 5 gallon bags. I learned not to put more than about 4 gallons in them - not just for expansion, but because they can get quite hot and leaving room to add some cooler water gets it down to a nice warm shower temperature.

Enjoy!!!

[Marionwyatt49]

We installed a conventional 2 1/5 gal under sink water heater that is run off 110
Use our Honda 2000 generator for 10 min and voila hot water for two
Lots of brands we checked out the cheapest at$165.00 and installation with connectors etc added maybe another $20
Easy installation

[drcat]

A small co is developing a 12v DC 350w replacement heating element for regular 120v AC small hot water tank. System designed for boats with solar panels and comes with electronic brain that knows if excess solar energy is available and charge state of battery bank, etc.
To find out more look at youtube Sailing A B Sea #72 published June 7. The boat owners are beta testing the system. I have no involvement in co.

[john61ct]

It would take a lot of panels a long time to get any decent gallonage up to a high temp.

350W just is not that much.

I realize it's "free" if it would truly be wasted power otherwise,

and pre-warming can save propane,

just don't have too-high expectations.

[Shaneesprit]

Propane is the way to go for water heating, but really need boat details and it’s use? You say in the winter, which suggest you also need or have heating? Solar doesn’t work without sunny weather.
I had a weight issue, you could use a dosel powered coolant heater from a car, ( second hand if cost was an issue ) then heat exchanger to fresh hot water and have a heating system, draw back being you get heating in the summer if you want the water.
You can buy a 12volt power washer they are bloody useless but the pump would do for a shower, not sure why you are worried about pressurising the system? The pump is the easy part
There is plenty advice on here so post your design and I am sure advice will follow

[Amaleo]

At my wife’s request, I installed an RV water heater in our catamaran in spite of some manufacturers’ caveat that they are not for marine use. I placed it in a former V-berth compartment that is well ventilated and accessible only through a hatch forward of a bulkhead which separates it from the head/shower compartment. It is fueled by propane, but has no pilot light as it is started by an igniter operated from the lavatory, giving it enough time to heat the water before use. So it’s propane but so is our galley stove. RV water hesters are exposed to the outside, and that includes coastal campgrounds and salted roads where it snows, so I am not concerned about corrosion. Plumbing was done using shark-bite fittings.

[Buzzman]

The OP stated they had three problems: one - water tankage volume; two - moving the water via pump (electric being an issue); three - how to heat the water in the first place (both electric and gas being an issue).

As they specified a "shower" as the preferred solution, my response is not 100% 'on topic' but it may provide ideas for others.

When I was a child, my dad and my brother and I would go bushwalking (that's back-country hiking / backpacking for you Seppos, Canuks and Euro-trash).

We usually walked where there were downed trees and sticks for firewood, so only needed to carry a box of matches in order to supply heat. Minimalist. Getting the picture?

But, being conscious that these sticks were meant to rot down and/or provide home to micro-critters, and being responsible in not wanting to create wildfires or waste heat, we always made small, longitudinal 'abo fires' (aboriginal-style micro-fires). So not much heat, ergo not much water could be heated. And it saved on wood collection (guess whose job that was...).

We often had to carry water a fair distance from a water source, too, so water was 'limited' to say the least. We had a small rubberised-canvas, zip-top 'bucket'/container of about 2-3L capacity. Quite a lot for a small boy to lug any distance!

But we still needed to bathe to remove the sweat and dirt accumulated each day during walking/hiking.

No electric power, no bulky 'spraypaks', no tank to heat large qty of water, no gas stove....

So we used the the 'billy bath system'.

A 'billy' in the linga franca is a wire-handled aluminium 'pot' hung over the fire on a stick-tripod (tripod built from three sticks tied together with an old leather bootlace) to heat about 1L of water to bearable temperature (around 45degC). [The sticks were discarded so only the bootlace had to be carried from camp to camp. Minimalist, remember?]

A small 10-12" square micro-sponge-type cloth was then dipped in the hot water, and hard soap applied to it.

The sponge-cloth was then wiped over the skin, in much the same way one uses a flannel or sponge in the bath at home.

A second 'billy' was filled with clean water and a second sponge-cloth for rinsing off the soap.

The final rub down was with a micro-fiber towel (originally we used large 'Chux' wipes, then switched to micro-fibre after that was invented. We used Chux towels way back in the Seventies, micro-fibre from around the mid-Eighties).

The Chux towel or micro-fibre cloth dries in seconds (well, not many minutes, especially if hung near the heat of the fire), and is super-easy to wring out to 'almost' dry.

Three of us could bathe all over using just 2L of water.

On a boat, the billy-can could be a pot, saucepan, or a small bucket (filled from a kettle).

The big advantage for us, as bushwalkers, as we had to carry everything on our backs, was that the billy was needed to boil water for tea/coffee/cooking, so the only thing we added (weight-wise) was the soap (few grams) and the micro-fibre cloths (few grams). And the volume and weight of a micro-fibre sponge/cloth/towel was miniscule compared to a fluffy cotton towel - and dried in a tenth of the time! Easy to dry, and easy to pack away in a tiny space, like a backpack pocket.

Works fine on the smallest of boats with most minimal water supplies and systems, and limited storage. No need for power or pumps. Minimal water usage. Minimal energy requirement.

So whether you have an electric stove, or a meth-burner, or a gas-burner, you will have a source of heat.

However, unlike the back-country, light-weight-obsession, on a boat you could also carry one or more of the more bulky black-plastic-bag-type 'solar showers', which could (depending on daily insolation rates/latitude/weather) either totally heat or at least partially pre-heat the water for your bath/shower.

Another advantage of the 'billy-can bath' is that you can 'bathe' while standing in a shallow container - like a cat litter tray sort of size - and as you aren't using huge amounts of water, what does run off the body and into the container/tray can easily be tipped overboard without any need for the build up of soapy scum that would otherwise build up in the bilges or shower well inside the boat. Or just bathe in the cockpit....that has overboard drains, and rinse it after you've finished to prevent the build-up of soap scum...

So a 'removeable' shower base/container might be a worthwhile addition in smaller boats, for indoor use, and especially for the OP, as otherwise they'd need to still use an electric pump (or manual pump, or laborious hand-mopping-up) to rid the shower well/bilge of the excess shower run off.

This bathing methodology is often referred to in a derogatory way as the <<Insert racial/cultural vilification description>> bath.

In our case, due to my mum having grown up in NZ, it was known as the 'Maori bath'. But it could equally have been the 'Abo bath'. Or the 'Mexican bath', or the 'Irish' bath, or the 'Polish' bath, or the 'Hillbilly' bath, depending on your racial/social vilification preference.....

But I much prefer the 'billy can bath'.....

YMMV

A final thought, to add to those up thread, especially in regard to the pump-up sprayers (I am soooo going to test this method when I get aboard) is that most/many have either a spring-loaded trigger or a flip on/off switch to control the flow of water.

Equally, so do some of the 12V-submersible-pump solutions from eBay or camping stores.

This is important if you are using either a pump-sprayer or a 12V pump to limit water wastage (again, important to the OP).

My old 4WD camp shower utilised a Whale 12V submersible pump, but rather than have it run continually, I had it wired through a switch so I could pump pre-heated water from a 40L jerry-can to a shower head hung from a tree or the roof rails on the vehicle, freeing both hands for shampooing (one handed hair washing is SOOOO wrong).

So I'd run the shower to get wet, then switch off the pump in order to soap up, and then switch it back on to rinse off. Again, on the vehicle, water was in short supply.

Also, to add to the negative comments about 'on demand' water heaters, and especially the smaller so-called 'portable' units like the Coleman et al, if you turn off the water flow on the rose/hand piece, the water still in the heated coil gets very hot (unless you have a super-sophisticated unit that senses pressure drop and turns off), in which case the water cools, so in order to have low water usage, you end up with either too hot or too cold or fluctuating water temps. Utter rubbish. And the small screw-on propane cylinders are not cheap. And don't last long.

One trick I learned when testing 'outback water heaters' 20 years ago for a 4WD magazine here in Oz, is that if you arrange the water outlet (rose/handpiece) initially so that it flows back into the container of water you are heating, so it cycles through the heater and back into the container, you have the advantage that the water heats more quickly, and can achieve a hotter temperature than 'constant flow heating', and you can turn off the heat source (which might be the vehicle's engine) while you're actually standing about bollock naked in the bush (or cockpit of the boat). Making for a quieter, more peaceful, more relaxing shower. You can also keep it cycling to continue raising the water to 'washing up' temperatures.

Final thought:- while others up-thread talked about the 'pressure' of the shower/pump, the more important specification is the flow rate at whatever pressure.

So while a fully-featured onboard shower setup (maybe a manufacturer/builder fitted unit) might use a 12/24V pump rated at 50psi and 45L/min, this is excessive when on small boats, outback in 4WD or where water or energy is severely limited.

Many of the automobile shower makers use (or offer) a 'low volume, lower pressure' pump option such as the Flojet 12V 8.5L/min 35psi unit, which is more than adequate to shower with.

My old Whale 12V pump (psi rating unkown but low) was around 4L/min, so that 40L jerry can was a "good" 10min shower, or enough for two pax to have a 5min shower each, at full flow. Longer if you switched the flow off while soaping up or massaging shampoo into the scalp. So not a great 'shower' flow, but adequate.

And the Whale pump was rated for an 'aquarium' or 'water feature' (although a top-quality design) so to save even more dollars, an eBay el cheapo (or Amazon) version of a 12V submersible pump might be good enough. Especially as the cost would allow a spare to be kept.

Camping stores often sell 'kits' for 'camp showers' that feature the rose/handpiece, hose and 12V submersible pump for AUS$ 10-30. Add a 20L bucket (you should have one onboard anyway) and a AUS$10 'solar bag' and - in the temperate/tropics at least - that might be the only costs to have a viable 'showering solution' on a boat as limited in resources and space as the OP's.

Scale up from there as space, funds, preferences allow.

Enjoy!

[rmlarson1098]

Originally Posted by Buzzman

The OP stated they had three problems: one - water tankage volume; two - moving the water via pump (electric being an issue); three - how to heat the water in the first place (both electric and gas being an issue).

As they specified a "shower" as the preferred solution, my response is not 100% 'on topic' but it may provide ideas for others.

When I was a child, my dad and my brother and I would go bushwalking (that's back-country hiking / backpacking for you Seppos, Canuks and Euro-trash).

We usually walked where there were downed trees and sticks for firewood, so only needed to carry a box of matches in order to supply heat. Minimalist. Getting the picture?

But, being conscious that these sticks were meant to rot down and/or provide home to micro-critters, and being responsible in not wanting to create wildfires or waste heat, we always made small, longitudinal 'abo fires' (aboriginal-style micro-fires). So not much heat, ergo not much water could be heated. And it saved on wood collection (guess whose job that was...).

We often had to carry water a fair distance from a water source, too, so water was 'limited' to say the least. We had a small rubberised-canvas, zip-top 'bucket'/container of about 2-3L capacity. Quite a lot for a small boy to lug any distance!

But we still needed to bathe to remove the sweat and dirt accumulated each day during walking/hiking.

No electric power, no bulky 'spraypaks', no tank to heat large qty of water, no gas stove....

So we used the the 'billy bath system'.

A 'billy' in the linga franca is a wire-handled aluminium 'pot' hung over the fire on a stick-tripod (tripod built from three sticks tied together with an old leather bootlace) to heat about 1L of water to bearable temperature (around 45degC). [The sticks were discarded so only the bootlace had to be carried from camp to camp. Minimalist, remember?]

A small 10-12" square micro-sponge-type cloth was then dipped in the hot water, and hard soap applied to it.

The sponge-cloth was then wiped over the skin, in much the same way one uses a flannel or sponge in the bath at home.

A second 'billy' was filled with clean water and a second sponge-cloth for rinsing off the soap.

The final rub down was with a micro-fiber towel (originally we used large 'Chux' wipes, then switched to micro-fibre after that was invented. We used Chux towels way back in the Seventies, micro-fibre from around the mid-Eighties).

The Chux towel or micro-fibre cloth dries in seconds (well, not many minutes, especially if hung near the heat of the fire), and is super-easy to wring out to 'almost' dry.

Three of us could bathe all over using just 2L of water.

On a boat, the billy-can could be a pot, saucepan, or a small bucket (filled from a kettle).

The big advantage for us, as bushwalkers, as we had to carry everything on our backs, was that the billy was needed to boil water for tea/coffee/cooking, so the only thing we added (weight-wise) was the soap (few grams) and the micro-fibre cloths (few grams). And the volume and weight of a micro-fibre sponge/cloth/towel was miniscule compared to a fluffy cotton towel - and dried in a tenth of the time! Easy to dry, and easy to pack away in a tiny space, like a backpack pocket.

Works fine on the smallest of boats with most minimal water supplies and systems, and limited storage. No need for power or pumps. Minimal water usage. Minimal energy requirement.

So whether you have an electric stove, or a meth-burner, or a gas-burner, you will have a source of heat.

However, unlike the back-country, light-weight-obsession, on a boat you could also carry one or more of the more bulky black-plastic-bag-type 'solar showers', which could (depending on daily insolation rates/latitude/weather) either totally heat or at least partially pre-heat the water for your bath/shower.

Another advantage of the 'billy-can bath' is that you can 'bathe' while standing in a shallow container - like a cat litter tray sort of size - and as you aren't using huge amounts of water, what does run off the body and into the container/tray can easily be tipped overboard without any need for the build up of soapy scum that would otherwise build up in the bilges or shower well inside the boat. Or just bathe in the cockpit....that has overboard drains, and rinse it after you've finished to prevent the build-up of soap scum...

So a 'removeable' shower base/container might be a worthwhile addition in smaller boats, for indoor use, and especially for the OP, as otherwise they'd need to still use an electric pump (or manual pump, or laborious hand-mopping-up) to rid the shower well/bilge of the excess shower run off.

This bathing methodology is often referred to in a derogatory way as the <<Insert racial/cultural vilification description>> bath.

In our case, due to my mum having grown up in NZ, it was known as the 'Maori bath'. But it could equally have been the 'Abo bath'. Or the 'Mexican bath', or the 'Irish' bath, or the 'Polish' bath, or the 'Hillbilly' bath, depending on your racial/social vilification preference.....

But I much prefer the 'billy can bath'.....

YMMV

A final thought, to add to those up thread, especially in regard to the pump-up sprayers (I am soooo going to test this method when I get aboard) is that most/many have either a spring-loaded trigger or a flip on/off switch to control the flow of water.

Equally, so do some of the 12V-submersible-pump solutions from eBay or camping stores.

This is important if you are using either a pump-sprayer or a 12V pump to limit water wastage (again, important to the OP).

My old 4WD camp shower utilised a Whale 12V submersible pump, but rather than have it run continually, I had it wired through a switch so I could pump pre-heated water from a 40L jerry-can to a shower head hung from a tree or the roof rails on the vehicle, freeing both hands for shampooing (one handed hair washing is SOOOO wrong).

So I'd run the shower to get wet, then switch off the pump in order to soap up, and then switch it back on to rinse off. Again, on the vehicle, water was in short supply.

Also, to add to the negative comments about 'on demand' water heaters, and especially the smaller so-called 'portable' units like the Coleman et al, if you turn off the water flow on the rose/hand piece, the water still in the heated coil gets very hot (unless you have a super-sophisticated unit that senses pressure drop and turns off), in which case the water cools, so in order to have low water usage, you end up with either too hot or too cold or fluctuating water temps. Utter rubbish. And the small screw-on propane cylinders are not cheap. And don't last long.

One trick I learned when testing 'outback water heaters' 20 years ago for a 4WD magazine here in Oz, is that if you arrange the water outlet (rose/handpiece) initially so that it flows back into the container of water you are heating, so it cycles through the heater and back into the container, you have the advantage that the water heats more quickly, and can achieve a hotter temperature than 'constant flow heating', and you can turn off the heat source (which might be the vehicle's engine) while you're actually standing about bollock naked in the bush (or cockpit of the boat). Making for a quieter, more peaceful, more relaxing shower. You can also keep it cycling to continue raising the water to 'washing up' temperatures.

Final thought:- while others up-thread talked about the 'pressure' of the shower/pump, the more important specification is the flow rate at whatever pressure.

So while a fully-featured onboard shower setup (maybe a manufacturer/builder fitted unit) might use a 12/24V pump rated at 50psi and 45L/min, this is excessive when on small boats, outback in 4WD or where water or energy is severely limited.

Many of the automobile shower makers use (or offer) a 'low volume, lower pressure' pump option such as the Flojet 12V 8.5L/min 35psi unit, which is more than adequate to shower with.

My old Whale 12V pump (psi rating unkown but low) was around 4L/min, so that 40L jerry can was a "good" 10min shower, or enough for two pax to have a 5min shower each, at full flow. Longer if you switched the flow off while soaping up or massaging shampoo into the scalp. So not a great 'shower' flow, but adequate.

And the Whale pump was rated for an 'aquarium' or 'water feature' (although a top-quality design) so to save even more dollars, an eBay el cheapo (or Amazon) version of a 12V submersible pump might be good enough. Especially as the cost would allow a spare to be kept.

Camping stores often sell 'kits' for 'camp showers' that feature the rose/handpiece, hose and 12V submersible pump for AUS$ 10-30. Add a 20L bucket (you should have one onboard anyway) and a AUS$10 'solar bag' and - in the temperate/tropics at least - that might be the only costs to have a viable 'showering solution' on a boat as limited in resources and space as the OP's.

Scale up from there as space, funds, preferences allow.

Enjoy!

Good idea. We Yanks would usually describe that as a 'sponge bath'. But if it's just guys out roaming around, afoot or at sea, why bathe at all?

[john61ct]

Maybe a separate not-showering thread would be good.

Pretty sure OP was in search of reasonable methods that would supply hot water for at least close to proper showers.

[Shaneesprit]

I am intending to add my shower outside below the boom where it’s wet already, I don’t see the problem in wearing swimming trunks / Bikini for females - and showering on deck, but with hot water
And you can get a pressure pump for very little money.

[Captain Bill]

Riki, if you have a 2x2 ft square area available on your deck you might consider a Heliatos solar thermal panel system. They suggest one 2x2ft panel for every 10 gallons of hot water capacity. They even sell a marinized version of the panel. They sell a complete kit that includes a small solar voltaic panel to run the circulation pump. My experience with solar bags and the like is that they get cold soon after the sun gets low in the afternoon. You do not seem to want a pressurized water system and the Heliatos panel does not require one. Plumbing such a panel into a small insulated tank will provide plenty of hot water. I'm planning on adding one to my boat to deal with hot water when I'm anchored out for a long time. The downside of my new solar panels is that I don't run the genset very often which is how I used to make hot water at anchor.

[Buzzman]

Originally Posted by rmlarson1098

Good idea. ..... why bathe at all?

You'd definitely be sailing on your own, I think! lol

Even at home I tend to have a 'sponge bath' more often than a full shower. I usually only do so once a week to wash the lankness out of the locks, but I've found if I keep them buzzcut short I don't even need to do that.

'Course, if I do any exercise or outdoor work, I tend to need a shower then also. But I've never been 'at sea' long enough to get covered with salt, but imagine I'd want to bathe more often then.

But otherwise, this whole 'bathing' lark is for the birds.

We humans managed around 300,000 years of 'development' without the need for either a flushing toilet or a shower.

I call it 'preserving our Paleo heritage'.

YMMV.....

[tdtrimmer]

Check out custommarineproducts.com. They have a radiant water heating system that attaches to the back of a solar panel. Water is circulated from the water heater or storage tank through a heat exchanger mounted behind a solar panel. Heat water to 100-110 F degrees on sunny days. Pump only draws 2 watts.

[john61ct]

Fantastic concept.

Any links to reviews by real users, especially about reliability over time.

Bit Rube Goldbergish. . .

[warrior 90]

I am also interested. Always thought direct solar water heating is an interesting option.... more efficient conversion rate ....but I have never seen or heard any reliable opinion the mentioned system

However in the particular system mentioned I don´t believe it is the most efficient. Those solar panels we usually use on the boat for energy production are quiet slow in heating water. The added benefit would be the cooling effect on the solar which makes them more efficient. However that would only be till reach max temp

I am thinking more of some evacuated vacuum tubes They are really ultra efficient when it comes to heating water with solar, even with just hazle sky. They are very sensitive to UV light and have a much higher working temp.
Check out those videos. I think this offers great DIY design possibilities for a decent price at 150 $ for 10 tubes,....or complete system 350 $
from....
https://dakotalithium.com/product/10...v=1d7b33fc26ca

https://www.youtube.com/watch?v=2d36fhHc03Y

https://www.youtube.com/watch?v=mKmzzT-c7Ec

https://www.youtube.com/watch?v=PmdETutF3IM

they say....
5 gallons of water from room temperature to 122 degrees in 4 hours

ENERGY PER HOUR
Heats water at a rate of 165 watts. 12v Solar Water Pump (one unit). Max water flow: 20liters/min. Rated voltage: 12 V DC, Rated Current: 2.8A

SIZE & WEIGHT
Unit measures 23" wide, 22" tall, 3" thick, weighs 19 lbs.

What I also like about this system.... the tubes are more effective and flexible to angle of sun and shade tolerance then the flat panels. I could think of a lot of good places to mount a few of those tubes. The only tricky part is sending the hot water to the tank/ standard water heater but so it would also be with the mentioned system


Another interesting concept is the friction heater based on an electric motor with a rotating disk/ shaft, magnets and a coil of electric copper tubing.
Too bad, only have tube videos and have no numbers on efficiency

https://www.youtube.com/watch?v=BJZzTc2zJ4M

I think on a boat it´s an interesting concept because it could also be integrated with the another real issue .... heating the boat !

Of course it will cost a few amps. There is no such thing as free energy
But so does any other reliable system of water heater less the cooling system of the engine as long as You use it for propulsion.
Running an electric motor for an hour or 2 does not sound like something out of this world and I can imagine a quiet easy and clean install.
Maybe, also great way to control and protect the top end of a Lithium battery from over charging ?

Yes, there are plenty of videos experimenting. Maybe it´s only a question of the right relation of the components
Too bad I don´t have enough facts but here are 2 videos that tease me to think

https://www.youtube.com/watch?v=RQjPSsIWDvg

This guy shows some design details and it seems like real numbers. His second model is interesting.
And what if this copper tube is just some how mounted in a standard 5 gallon water heater tank like many have on board ?

Is it more efficient then just a simple DC water heating element ?

Will it heat the water fast ?????

https://www.youtube.com/watch?v=NivItikx0AU