Source of hot water while cruising

[sailorboy1]

If you tape your cell phone to your hot water tank and put it on a read Internet forum loop it will heat the water forever

[Dockhead]

Originally Posted by smj

You seem very opinionated on something you've never experienced?

I've never experienced being boiled in oil, either, but I don't think I don't have a right to an opinion, about not WANTING to experience it . . . .

[smj]

Originally Posted by Dockhead

I've never experienced being boiled in oil, either, but I don't think I don't have a right to an opinion, about not WANTING to experience it . . . .

Absolutely! But let's face it, sailing isn't risk free either.


Sent from my iPhone using Cruisers Sailing Forum

[smj]

Originally Posted by sailorboy1

If you tape your cell phone to your hot water tank and put it on a read Internet forum loop it will heat the water forever

I do believe your onto something

[Seafarer7]

I have a similar (but less expensive and part DIY) system to Paul L for year round on-demand hot water. I installed an Espar 5 hydronic heater with fan driven radiators for space heating. Then I installed a $180 high surface heat exchanger in the hydronic coolant loop for unlimited on-demand hot water. Works very well.

Brazed Plate Heat Exchanger, 5x12- 30 Plate Water to Water Heat Exchanger 60,000 BTU 1" MPT B3-32-30 https://www.amazon.com/dp/B01DOC0O4C..._eEKSBb06Z1YNA

[sguerrero1971]

I just installed a 12volt 200watt hot water heater element with a thermostat to use with my Solar. I don't have enough usage out of it to be able to tell you if it will work long term, but it was easy to install and I'm hoping between it using the motor our generator and the solar we can have hot water when ever we need it.

Submersible DC Water Heater Elements - Missouri Wind and Solar

I've seen a lot of mention of Propane, just thought I would throw this into the mix too.

[SVRocinante]

Wow! Lots of replies!

For what it’s worth, I think Cheechako gave me the answer I needed - just run the darn engine for 30 minutes,it will do no harm. Yes, I know it’s an ongoing debate, but I’ve made my piece with it.
link to reply: http://www.cruisersforum.com/forums/...ml#post2730611

Sailor647 might be on to something as well, and I’ll be looking at trying to further insulate my tank...
link to reply: http://www.cruisersforum.com/forums/...ml#post2730653

noelex 77 has a very cool setup, don’t know if I can make it work on Rocinante, but thinking about it!
link to reply: http://www.cruisersforum.com/forums/...ml#post2730693
link to 2nd reply: http://www.cruisersforum.com/forums/...ml#post2730721

NYSail had a nice hack to make a solar shower a bit more user friendly on a boat!
link to reply: http://www.cruisersforum.com/forums/...ml#post2730722

And finally, CaptTom provided some good thoughts on using the genset - unfortunately, I’ve got mine stored deep in the port lazarette and only dig it out if it’s been too long without enough wind for my windgen. That said, he & others made a good case for using it instead of my engine, so I’ll be considering a new location for it!
link to reply: http://www.cruisersforum.com/forums/...ml#post2730932

Thanks again everyone!

[Mike Banks]

Use a solar heater and small storage tank--well insulated, with a thermostat and solar powered pump. On-going costs zero.

[Bentwings]

I didn’t read the whole thread so maybe someone already has this.
In digging around for s fuel problem on my Westerbeke gen I discovered that there is some information in their owner manual that indicates using the hot water from the engine to heat water in a water tank with its own heat exchanger. Then the engine water is either plumbed back into the exhaust or simply dumped overboard if the unit has stack exhaust.

I had sketched out an idea for this very thing. Since it was another rainy and cold day and I was waiting for parts, I searched for various heat exchangers and hot water systems. I couldn’t find a kit but there are parts available so it wouldn’t be too hard to put together a much larger hot water supply. The hardest part is combining the heat exchanger with a water tank. Most boat don’t have an abundance of unused space but you can place a tank in a corner somewhere and easily double the 6-8 gallons most electric heaters supply.

I do precision TIG welding so fabricating a tank with an intergalactic heat exchanger would not be out of the question. It’s possible to put a system together with a separate tank and heat exchanger but it takes more room.

Additionally I’m looking at a modification to use something like a radiator with a fan to do the same thing for heating in the winter. The cost of electric power is pretty high and I don’t really feel safe using propane on a gasoline boat. Maybe it’s a non issue as I see the house boats down the line from me all use propane heat in the winter with gas motors. There just may not be much evaporation of the gas in the winter to be an issue especially if you run the bilge blowers.

I asked a Westerbeke tech guy about this and the lifespan of the gen. He said if the oil is monitored and changed regularly and you don’t overheat the motors they will last almost indefinitely, more so the diesel ones.

I wouldn’t want to run 24/7 with these gens but turning them on for the evening instead of electric would not be out of the question. I worked at a very large stationary engine builder and these motors typically ran 24/7 for years with only automatic oil changers and automatic coolant level maintenance.

Something to think about.

[CaptTom]

Originally Posted by Bentwings

I didn’t read the whole thread so maybe someone already has this.

I'm not really sure what you're suggesting here. Marine water heaters, with built-in engine loop heat exchangers, come in various capacities. Mine is 11 Gallons, mostly because that's what I had room for, and really all I needed.

"Bus heaters," which are just heat exchanger and fan combinations, are marketed specifically for marine use, again in many different sizes. Presumably you could also re-purpose one from an actual school bus.

[GaryBode]

This heater had a coil to heat water. And since you might need it to heat the cabin you're not using extra energy resources.

http://dickinsonmarine.com/product/n...diesel-heater/

[jpendoley]

Originally Posted by boatpoker

Just be aware that it may cause some insurance issues at your next survey. Not one of those appliances meets ABYC Standards.

I have a unit by a company called Precision Temp, believe it meets all applicable safety standards, big issue is having a sealed combustion chamber and direct overboard venting. All propane devices should be home runned from the tank-no t’s.

I love it. I only carry liability insurance as my boat is quite old, but am very comfortable with the unit.

[hpeer]

Originally Posted by john61ct

I never heard anyone considering that safe before.

Do you have a home run back to the outside tank for each appliance?

My understanding is a T join within the cabin space is dangerous.

We use this, totally outside.

https://www.walmart.com/ip/Zodi-Outb...hoCapIQAvD_BwE

There are more options now. Google ... propane camp hot water

[Bentwings]

I’m not looking at a combustion heater at all. What I’m suggesting/asking is using the hot water produced by the generator or main motor to provide heat just as the heater in your car does.. you can purchase very small stand alone units that often are used in Streetrods for cool weather use. It’s just a different form of heat exchanger.

Certainlybyouncan use thevgen to produce 110 VAC but it takes a white to get hot water forvshower and the tanks are not very big. Bybusing a liquid to liquid heat exchanger and an auxiliary tank you can have hot water anytime the gen is running. There are all kinds of valves manual, vacuum and electric used in the automotive aftermarket.

Westerbeke even notes using this system in the manual for my generator.

[Bill O]

Look up bus heaters like this one. They basically use an engine take off (similar set up to going to your water heater via an engine coil).

Essentially the bus heaters are a radiator w/fans to extract heat from the engine water.

Bill O.