Shower Hot Water Options

[Rustic Charm]

Originally Posted by DeepFrz

The Glind looks to me, just looking at the web site, that its made for larger engines such as you would find in an off road vehicle. You really need a regular marine calorifier (insulated hot water tank). They work well when engine runs for about 20 minutes if they are hooked up properly.

Yes, I think that's the case. The web page say's 40hp + but I sought their advice before buying mine and they said 38hp would be fine. Well, it' aint.

[Dockhead]

Originally Posted by Rustic Charm

Yes, I think that's the case. The web page say's 40hp + but I sought their advice before buying mine and they said 38hp would be fine. Well, it' aint.

Rustic, are you fresh or raw water cooled? What engine? Sorry if you've already posted this.

[Rustic Charm]

Originally Posted by Dockhead

Rustic, are you fresh or raw water cooled? What engine? Sorry if you've already posted this.

VP203T 38hp fresh cooled. I've got it plumbed immediately from the outlet of the thermostat

[Privilege]

Originally Posted by Dockhead

As others have said, the most efficient way to make domestic hot water is with engine waste heat. Diesel engines produce vast amounts of waste heat which is not hard to capture for heating water, and it's free. Forget propane, solar, and all those other methods.

...Well that depends. If you are running your engine anyway, then it makes sense to obtain hot water as a bi-product. However, if you have to run your engine in order to make hot water then it is a very inefficient way of obtaining hot water. I am also going to throw my hat in the ring for the LPG instantaneous hot water heater solution. I've had one on my boats for years. The only downside is that you need a flue. On my current boat, it flue's through a 3" hole on the deck covered by a cowl vent. I have two 20lb tanks which provide hot water and cooking for the stove. The two tanks last me roughly seven months...that's pretty efficient.

[robwilk37]

on a related subject...
a y-valve in your shower drain lets you rinse salt/sweat off with about a gallon of water, then recirculate the same gallon with minimal heat loss, then a new gallon to rinse the soap. a 20 minute hot 3 gallon fresh water shower at the end of a cold watch is the most decadent luxury on a long passage...

[Rustic Charm]

Originally Posted by Dolce Vita

There are new vent free tankless water heaters that operate on low pressure with redundant safety shutoff systems , the excel tankless is the one, it is avaliable at excelonlinestore.com

Tankless Gas Water Heater Low Pressure Startup 1 6 GPM LPG Ventfree Propane | eBay

This looks interesting. No flue is needed

[SV THIRD DAY]

Originally Posted by Rustic Charm

Tankless Gas Water Heater Low Pressure Startup 1 6 GPM LPG Ventfree Propane | eBay

This looks interesting. No flue is needed

So right now I run our Honda 2000 generator for an hour a day to heat up my 12gallon water tank for showers for the crew (4 people). If I can solve my hot water issue, then my Honda generator running almost goes away. So after reading the specs and data on this unit...well I'm in...I ordered one and will let you folks know how it works!

[crazyoldboatguy]

Originally Posted by Rustic Charm

Tankless Gas Water Heater Low Pressure Startup 1 6 GPM LPG Ventfree Propane | eBay

This looks interesting. No flue is needed

The space must be "properly vented". What does th ABYC say about this type of device. What would your insurance company say about it?

[Dockhead]

Originally Posted by Rustic Charm

Tankless Gas Water Heater Low Pressure Startup 1 6 GPM LPG Ventfree Propane | eBay

This looks interesting. No flue is needed

So you're still struggling with this . . .

In my opinion, you should not be adding new ways to heat water before you've sorted out your calorifier problem.

There is no way your engine coolant is not warm enough to make hot water. Fresh water cooled engines run at 80C or more, rarely at 70C. Domestic hot water is 50C to 60C. If your engine is running at less than 70C, then you've got a stuck thermostat or some other kind of problem, which will be harmful.

An instant-type calorifier --which does not store water -- is ok on a power boat maybe, but really not on a sailboat, since the engine has to be running that moment when you want to take a shower. Why don't you start by installing a normal calorifier with a tank? Weren't you asking about this in the other thread?

If you want to future proof it, buy one with two coils so you can add a hydronic heater later if you want. Make sure it has a 240v immersion heater of a size which your shore power can handle, so you can run it off shore power. 1kW would probably be ok, needing about 4.5 amps. If you typically have 16 amp service where you are, and the rest of your system is up to it, then you might stretch to 1.5kW, which is what I use.

A good calorifier will maintain reasonable temp for up to 24 hours after you shut the engine down. So it means you can have a couple of showers anytime within 24 hours of when you just motored for half an hour or so to get into that anchorage.

That's what 99% of cruisers do, and it works great.

Forget the gas. If you want to be able to heat water independently from engine running and electricity, then your best bet is a small hydronic heater. Much, much more efficient, and you don't have to be buying propane all the time. It's completely safe, and yet another great benefit is you can plumb in a couple of radiators to heat the cabin as well.

Something like this:

Webasto Thermo Top C, auxiliary, night, diesel water heater, warranty | eBay. The whole kit is only 325 pounds.

The Webasto and others of this type have forced air burners, so you don't need to cut a hole in the cabin top. It exhausts through the transom. They are quite easy to install. Zero explosion risk. No combustion products dumped into the cabin air.

The gas device you referenced above just exhausts into the cabin. Its claim to fame is that it can sense oxygen depletion and shut down before killing someone. What a comfort! Not. This is not designed for boats, with small volumes of interior space!

But, in my opinion, this is optional. If you get your calorifier sorted, that will probably be all you need. I would add the hydronic heater only if you want cabin heating, and get the third way of making hot water as a bonus.


Hydronic heating is awfully nice. You get a warm cabin and hot water simultaneously. Uses diesel fuel from the main tank so completely safe, and is cheaper to run than other heat sources. Downside is they need service about every 2 years, and can be persnickety (I'm having some trouble with my system right now).


One other heat + hot water system you might think about is a bulkhead pot burner heater, like a Sigmar, Dickenson, etc. You can get a loop to make hot water with them. They are simpler and more reliable than hydronic, don't need electrical power, but don't distribute the heat as well, and you must cut a hole in the deck for the flue.

[Rustic Charm]

Originally Posted by Dockhead

So you're still struggling with this . . .

In my opinion, you should not be adding new ways to heat water before you've sorted out your calorifier problem.

There is no way your engine coolant is not warm enough to make hot water. Fresh water cooled engines run at 80C or more, rarely at 70C. Domestic hot water is 50C to 60C. If your engine is running at less than 70C, then you've got a stuck thermostat or some other kind of problem, which will be harmful.

An instant-type calorifier --which does not store water -- is ok on a power boat maybe, but really not on a sailboat, since the engine has to be running that moment when you want to take a shower. Why don't you start by installing a normal calorifier with a tank? Weren't you asking about this in the other thread?

If you want to future proof it, buy one with two coils so you can add a hydronic heater later if you want. Make sure it has a 240v immersion heater of a size which your shore power can handle, so you can run it off shore power. 1kW would probably be ok, needing about 4.5 amps. If you typically have 16 amp service where you are, and the rest of your system is up to it, then you might stretch to 1.5kW, which is what I use.

A good calorifier will maintain reasonable temp for up to 24 hours after you shut the engine down. So it means you can have a couple of showers anytime within 24 hours of when you just motored for half an hour or so to get into that anchorage.

That's what 99% of cruisers do, and it works great.

Forget the gas. If you want to be able to heat water independently from engine running and electricity, then your best bet is a small hydronic heater. Much, much more efficient, and you don't have to be buying propane all the time. It's completely safe, and yet another great benefit is you can plumb in a couple of radiators to heat the cabin as well.

Something like this:

Webasto Thermo Top C, auxiliary, night, diesel water heater, warranty | eBay. The whole kit is only 325 pounds.

The Webasto and others of this type have forced air burners, so you don't need to cut a hole in the cabin top. It exhausts through the transom. They are quite easy to install. Zero explosion risk. No combustion products dumped into the cabin air.

The gas device you referenced above just exhausts into the cabin. Its claim to fame is that it can sense oxygen depletion and shut down before killing someone. What a comfort! Not. This is not designed for boats, with small volumes of interior space!

But, in my opinion, this is optional. If you get your calorifier sorted, that will probably be all you need. I would add the hydronic heater only if you want cabin heating, and get the hot water as a bonus.

No, I'm not going to LPG gas. I will be retaining an LPG stove, but I want it next year to be certified. I'd never get it certified with an LPG HW system.

I currently have a Glind Portable 4wd Hot Water Systems | Camping Showers | Glind - Glind Hot Water Heat Exchanger Camping Showers for 4WD and Marine system. But it doesn't heat the water long enough to even wash my hands.

I have a webasco cabin heater.

My preferred option is that I want a storage tank connected to my engine so that my water is heated from the engine.

What's this hydronic heater your referring too?

[Dockhead]

Originally Posted by Rustic Charm

No, I'm not going to LPG gas. I will be retaining an LPG stove, but I want it next year to be certified. I'd never get it certified with an LPG HW system.

I currently have a Glind Portable 4wd Hot Water Systems | Camping Showers | Glind - Glind Hot Water Heat Exchanger Camping Showers for 4WD and Marine system. But it doesn't heat the water long enough to even wash my hands.

I have a webasco cabin heater.

My preferred option is that I want a storage tank connected to my engine so that my water is heated from the engine.

What's this hydronic heater your referring too?

If you've already got a Webasto cabin heater, then you don't want a hydronic heater which duplicates its function. I presume it's an Air Top? No radiators? If it's the kind with radiators or fan coils, then it's hydronic (that means -- a heater which uses water to distribute the heat, rather than air) and it's simple to hook it up to a calorifier.


If I were you, I would first check to make sure that you're getting (a) circulation of (b) actually hot coolant to your existing calorifier. It's surprising that it doesn't work. It should work; there are zero moving parts. Maybe it's installed wrong, on the wrong side of the thermostat? Or there just isn't any circulation maybe.


If you get it working but still don't like it, then put in a calorifier with a tank, inside or next to your heads, and add a booster pump to make sure you get strong circulation of coolant. You need to be sure that the coolant loop is correctly connected to the engine, though, and that the engine is running at the proper temperature.

Something like this maybe:

http://www.isotherm-parts.com/index....oducts_id=1929

[Rustic Charm]

Originally Posted by Dockhead

If you've already got a Webasto cabin heater, then you don't want a hydronic heater which duplicates its function. I presume it's an Air Top? No radiators? If it's the kind with radiators or fan coils, then it's hydronic (that means -- a heater which uses water to distribute the heat, rather than air) and it's simple to hook it up to a calorifier.

If I were you, I would first check to make sure that you're getting (a) circulation of (b) actually hot coolant to your existing calorifier. It's surprising that it doesn't work. It should work; there are zero moving parts. Maybe it's installed wrong, on the wrong side of the thermostat? Or there just isn't any circulation maybe.

If you get it working but still don't like it, then put in a calorifier with a tank, inside or next to your heads, and add a booster pump to make sure you get strong circulation of coolant. You need to be sure that the coolant loop is correctly connected to the engine, though, and that the engine is running at the proper temperature.

Something like this maybe:

http://www.isotherm-parts.com/index....oducts_id=1929

Yep, the isotherm is what I was looking at. I've even found a local supplier I have emailed and waiting a reply for cost.

My engine is definately operating at the correct temp. I've checked that out before. But it just won't heat the water going through the Glind. I did originally have it plumbed wrong, but since had a mechanic check it out and tell me where to connect on the Volvo Penta 2003T. But, still not enough to operate the Glind.

[Kokanee]

I agree with Dockhead 100%.


It is likely you are not getting enough coolant circulation from your engine through the calorifier (heat exchanger). Possible wrong hook up to engine, air lock, or wrong placement of calorifier. It should be mounted below the engine connections to avoid air lock problems.

Pull off the return hose at the engine, block the inlet point on the engine, and then start engine with the hose in a bucket to check that you have good steady circulation of warm water. (equal flow rate to the shower hot water you are using).

I haven't used this brand before, but with a well designed heat exchanger, you should get an increase in water temperature of about 30 degrees Celsius over the cold water coming in.

If the heat exchanger is simply to small for the job, you may have to use a tank. A bit more plumbing and space required, but you'll have hot water for 6-8 hours after running your engine (or until you use it all). It will take longer to heat up, though.

I have a home-built stainless tank with just a few coils of copper pipe for engine coolant to circulate in the bottom of the tank. It works a treat, giving me 50-60 degree C water.

[Rustic Charm]

Originally Posted by Kokanee

I agree with Dockhead 100%.


It is likely you are not getting enough coolant circulation from your engine through the calorifier (heat exchanger). Possible wrong hook up to engine, air lock, or wrong placement of calorifier. It should be mounted below the engine connections to avoid air lock problems.

Pull off the return hose at the engine, block the inlet point on the engine, and then start engine with the hose in a bucket to check that you have good steady circulation of warm water. (equal flow rate to the shower hot water you are using).

I haven't used this brand before, but with a well designed heat exchanger, you should get an increase in water temperature of about 30 degrees Celsius over the cold water coming in.

If the heat exchanger is simply to small for the job, you may have to use a tank. A bit more plumbing and space required, but you'll have hot water for 6-8 hours after running your engine (or until you use it all). It will take longer to heat up, though.

I have a home-built stainless tank with just a few coils of copper pipe for engine coolant to circulate in the bottom of the tank. It works a treat, giving me 50-60 degree C water.

I've mounted mine on top of the engine

[Dockhead]

Originally Posted by Rustic Charm

I've mounted mine on top of the engine

Aha!

Air lock city!!

There's your problem.

Tank-type calorifier is much better on a sailboat, but if you don't feel like spending the money, you really ought to be able to get this one to work.

They are dead simple, zero moving parts, and MUST work as long as you are getting circulation of hot coolant through it. This requires no air, and so must be below, not above the engine!! Or else you have to put a header tank with radiator cap ABOVE the heater.