Hot water

[Frank 101]

Our new to us single hull sail boat has a hot water tank heated by the main motor, which I’m not in favour of. The boat has two gas bottles for the stove. We also own a caravan which has two gas bottles and a stove, but the water heater is gas too. I know the issues of boats going boom because of gas leaks, but is there another reason why boats dont have hws’ that run on gas? We also have 250 watts of solar panels and 3 new 125 watt agm batteries. Is it feasible to run an electric hws through an inverter just for showering? Looking at options and wondering what others do for hot showers. And yes I do know about bladders being left in the sun, but it’s not always sunny!

[Joh.Ghurt]

It largely depends on where you are and how you use th eboat.

If you're in rather cold climates, you need a cabin heater anyway, often something like a Webasto hot air heater or a Refleks stove, both using diesel. Both are better options to provide hot water and the fuel is easier to come by.

If you're sailing around warm areas, the use of hot water is often reduced. In these areas, it sometimes makes sense to heat the water electrically either with overflow from panels or via genset. If you motor around often, the engine will provide free hot water. That's a nice bonus. For the cheapskates like me, solar showers on deck are also an option.

If you're mostly day-sailing, hot water isn't usually a big issue.

These things often lead to the the conclusion, that while a propane based heater would work perfectly fine, it's isn't always the preferred solution. On an RV, the situation is different.

[skipmac]

My boat came with a dual hot water heater, engine and electric (120V AC). It was failing and leaking which would compromise engine cooling so when I replaced it I removed the engine option and went straight electric.

Have a Honda EU2000 portable generator and using that can make scalding hot water in less than 10 minutes in a 5 gallon heater. Plenty for at least 3-4 hot boat showers IE don't let the water keep running while you soap up.

[Frank 101]

Gene is a good idea and one came with the boat. May be an issue in a crowded area though. Have read some threads where the ops were complaining about gene noise

[LittleWing77]

Joh has covered it pretty well.

As you get immersed in your new boat ownership, you'll find that the KISS (keep it simple, silly) really, really applies on a sailboat.

Every time a new system is installed, it means more maintenance and peripheral "gets". For instance, if you're sailing in the Bahamas, I understand certain kinds of gas bottles are impossible to get - so much so that people have removed their entire galley cooking system and refit with something else completely so that compatible fuel can be obtained in that cruising area.

The other consideration is space. In a sailboat space is always at a premium - which is why the engine hot-water heating is great - combines two functions, actually three functions in one. When not charging batteries by trickle-down solar, you'll be running your engine for charging anyway - so why not the side-benefit of hot water as well?

I would suggest if the boat is new to you, Frank, that yes, you do some research into various systems, but hold off for at least a full season of sailing, if not a full year, to get to know the systems already installed on this new-to-you boat so you give yourself a chance to understand their overall utility and how the boat's systems fit into your life aboard.

Fair winds,
LittleWing77

[Joh.Ghurt]

Originally Posted by LittleWing77

I would suggest if the boat is new to you, Frank, that yes, you do some research into various systems, but hold off for at least a full season of sailing, if not a full year, to get to know the systems already installed on this new-to-you boat so you give yourself a chance to understand their overall utility and how the boat's systems fit into your life aboard.

This advice is gold. When I got my 40 year old boat, I had great ideas how to make things better and what I need to add or improve.

Some turned out to be true, but in many cases, the project were delayed due to time and money restraints. While using the boat, I started to understand the better why certain things were the way they are and things I thought were absolutely necessary became very optional and other things I didn't even think about turned out to need a lot more urgent attention.

Hot water was one of these topics, where the combination of 220v from the dock / generator plus solar showers turned out totally sufficient not to bother with heating the water from the heat-exchanger (which doesn't offer a tap for the hot water heating). I would like to have it, but I'm not ready to get a new engine heat exchanger for this.

[skipmac]

Originally Posted by Frank 101

Gene is a good idea and one came with the boat. May be an issue in a crowded area though. Have read some threads where the ops were complaining about gene noise

The noise is certainly a concern and good to think about it as a good neighbor. The Honda is supposed to be very quiet and in relative terms I guess it isn't bad but certainly not silent. In a quiet anchorage it would definitely be audible on other boats. However, you could run it earlier in the day and a decent hot water heater would keep the water plenty warm for showers in the evening.

I can run mine late afternoon and still have very warm water the next morning.

[rwidman]

re: "Our new to us single hull sail boat has a hot water tank heated by the main motor, which I’m not in favour of."

Why? That system works very well and is standard equipment on most boats that have water heaters installed. It works just fine.

An electric water heater draws a large amount of current over a long period of time. So do the math if you want, but I suspect you will have to have a very large battery bank to heat water electrically and you will have to run the engine for a long time to recharge the batteries.

You might as well just use the waste heat from the engine to heat the water in the first place.