Heating Hot Water From Engine

mine has heat exchangers for the hydronic heating system that the engines and hot water heater are connected to. The engines are pre-heated by the hydronic heater and they provide heat to the hydronic system when running.

I need to replace the heater hoses that run from the heat exchanger to the hot water heater. My question is should I sue silicone or rubber hose?

In case there are any bottom feeders here (like me), the discussion on another board relative to this topic, is the best way to get the most out of a Sun Shower rather than the technology in achieving the optimum temperature of an engine heating water system.
Amazon.com : Stearns SunShower 5.0 with 4-5 showers (Capacity- 5 gallons) : Portable Camping Shower Gear : Sports & Outdoors
For some cruisers, a Sun Shower is all it takes.

My wife and I used a Sun Shower (w/ homemade raincatcher) for the three years we lived aboard a pre-trawler 27' sailboat...using the small sailboat for much the same purpose as the big trawler cruiser guys do here...just to be out experiencing the wonders of the water.

This group was the focus of much of my (lurking) trawler research. While the group is inspiring, it is very intimidating with talk of ‘quality’ vessels and ‘must have’ technology. This led me to a trawler purchase which was perhaps the low point of my boating experiences.

Probably 99% of those here can appreciate that the trawler ultimately didn’t cost me a penny. I put her into charter service and the folks who took her out were absolutely great (and easy on the boat). But unlike our previous boats, a slipped trawler requires considerable responsibility. Responsibility that I just wasn’t up for.

So the trawler had to go, but the draw of the sea didn’t subside. I found ways to keep the watery fire alive because I just couldn’t let go. That was/is my journey and my joy is to encourage others to keep the fire alive in spite of ‘quality’ and ‘technology’.

I chose to ‘infest’ my philosophies here because I’m thinking there are dreamers lurking like I did, who simply can’t afford to do it like the big guys. Perhaps I can give the dreamers a little low-tech inspiration.[FONT=&quot][FONT=&quot] However, [FONT=&quot]i[/FONT][/FONT]f there’s no one reading that finds my diatribes useful, fine, I’ll quit wasting bandwidth here, but if there are 5 positive replies to this post I’ll keep my bottom feeder cruiser ‘discoveries’ coming.[/FONT]

CaptTom said:

I haven't seen this, is this something new (in the past 4-5 years?). Sounds like a good solution. The mixing valve is also a good idea.

We just learned to live with super-hot water. We do the mixing at the sink or shower faucet, and like BayView said above, I assume that starting out at a higher temperature makes the water stay hot longer.

I love having "free" hot water at the end of (and during) every run. I'd never own a boat without it. To me, it's well worth the risk. I did have the hose between the engine and water heater let go on my last boat (a hanger failed and it was chafing on the steering arm.) I knew pretty quickly and was able to make the repair, refill the cooling system and be on my way. A very small price to pay for all the hundreds of hot showers and clean dishes we've enjoyed over the years.

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me too

Greetings,
Mr. j. I always look forward to your posts. Your perspective is indeed an encouragement to those of us in "the cheaper seats". Get 'er done.

"My question is should I sue silicone or rubber hose?"

At only 200F or so ,rubber hose is just fine for most folks.

Evans coolant with 260 as working engine temps , the silicone would be better.

Hi Alaskan Sea-Duction, Thanks again for the photos, I finally got a chance to get to the boat to try to find the same connections, below zero here in Maine! Do you use a circulation pump with this connection or does the engine provide the flow and which way does the flow go? I would assume the connection close to the thermostats is the outflow connection but the other connection a much larger diameter port on mine. I'm also going back behind the engine to get to the hot water heater so it seems a little far. I even thought of tapping off the pipe that comes out of the oil cooler going back to the turbo as there are numerous hose connections along this route.

Alaskan Sea-Duction said:

This what I found on WM


From Kuuma:

With the same ignition-protected design and features as the West Marine water heaters described above, Kuuma water heaters are installed as original equipment on many boats, including Sea Ray, Four Winns, Hunter, Beneteau, and Boston Whaler. Like West Marine water heaters, Kuuma water heaters are protected by a high-temperature limiter with automatic reset. Use of a magnesium anode is recommended to extend tank life.

• Port Sizes: Cold/hot in/out: 1/2" NPT, Engine coolant in/out: 5/8" (for hose)
• Draw: 12.5A @ 120V AC; 6.25A @ 240V AC
• Approvals: ETL
  [*]Warranty: One year against manufacturer defects

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Interesting, I am just overhauling my hot water system, replacing hoses etc. I have a the Force 10 made by Kuuma they are sold with a two year warranty here, all other specs are the same as above except we use 240Volts .

Not that that helps mind you. The unit has failed, with water leaking out the base, this just on three years.

I am getting fed up with appliances only just outliving their warranty period. On cheap purchases fair enough you get what you paid for, however when you spend $650 the product should have a reasonable operating life.

Well that's my whinge for today, back to the bilge to sort it out.

Keep it coming Jeffnick.
Regardless of affordability, there are great advantages for keeping it simple.

AusCan said:

Keep it coming Jeffnick.
Regardless of affordability, there are great advantages for keeping it simple.

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Grinder said:

Hi Alaskan Sea-Duction, Thanks again for the photos, I finally got a chance to get to the boat to try to find the same connections, below zero here in Maine! Do you use a circulation pump with this connection or does the engine provide the flow and which way does the flow go? I would assume the connection close to the thermostats is the outflow connection but the other connection a much larger diameter port on mine. I'm also going back behind the engine to get to the hot water heater so it seems a little far. I even thought of tapping off the pipe that comes out of the oil cooler going back to the turbo as there are numerous hose connections along this route.

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No pump here. I am not sure of flow diection as I have not had mine apart.....yet....

Jeff is the McGyver of boats and he has the best boat dog too!

The thread has given me an idea. We run on the bridge 99% of the time. In the fall and early winter when temps drop to the 30s and 40s it would be nice to have heat on the bridge. My hot water heater is 180F with the engine running. Has any one put a secondary pump off the hot water heater domestic water side to supply a HX on the bridge?

Greetings,
Mr. f. A definite possibility but this is probably easier and cheaper... Thunderbolt Heated Electric Socks cold feet foot warmers

fryedaze said:

The thread has given me an idea. We run on the bridge 99% of the time. In the fall and early winter when temps drop to the 30s and 40s it would be nice to have heat on the bridge. My hot water heater is 180F with the engine running. Has any one put a secondary pump off the hot water heater domestic water side to supply a HX on the bridge?

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I have a heat exchanger with a secondary pump but don't run water to the bridge...but could.

You can also just plumb to your lower dash to a heater there and use vents to defrost the lower windows and run a duct to the bridge to a floor register up there

Another set of photos from another 3208 from B.D. thread.

fryedaze said:

The thread has given me an idea. We run on the bridge 99% of the time. In the fall and early winter when temps drop to the 30s and 40s it would be nice to have heat on the bridge. My hot water heater is 180F with the engine running. Has any one put a secondary pump off the hot water heater domestic water side to supply a HX on the bridge?

Click to expand...

I asked this question about two years ago and got some good answers that went flying so far over my head, I had to get those heated socks.

But keep me informed as to what you do, as I have this issue and since my hot water line runs to the head under the pilot house, why not??

I just received the keel cooler from Fernstrum (nice unit btw) and my plan is to have the single Lugger coolant travel to the hot water heater (undecided on which brand) and to a box heater/defroster from Real. I am guessing that I would have a way to shut off/divert the box heater when I am in the warm climates and possibly also shut off/divert the water heater, although I don't know if that's necessary. I know that both the water heater and box heater must be mounted below the top of my expansion tank, and I am aware of needing anti scald overtemp protection on the water heater. I have read with much concern, that the water heater manufactures recommend using a non toxic antifreeze like Sierra when heated by engine coolant in case the heat exchanger within fails; they say poisonous antifreeze can get in to the domestic water supply. Is this something that anybody worries about? Also, am I asking too much from the Lugger's coolant circuit? Anybody recommend a water heater?

stevensibs said:

I just received the keel cooler from Fernstrum (nice unit btw) and my plan is to have the single Lugger coolant travel to the hot water heater (undecided on which brand) and to a box heater/defroster from Real. I am guessing that I would have a way to shut off/divert the box heater when I am in the warm climates and possibly also shut off/divert the water heater, although I don't know if that's necessary. I know that both the water heater and box heater must be mounted below the top of my expansion tank, and I am aware of needing anti scald overtemp protection on the water heater. I have read with much concern, that the water heater manufactures recommend using a non toxic antifreeze like Sierra when heated by engine coolant in case the heat exchanger within fails; they say poisonous antifreeze can get in to the domestic water supply. Is this something that anybody worries about? Also, am I asking too much from the Lugger's coolant circuit? Anybody recommend a water heater?

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We have a Lugger 1066T with a keel cooler. Our water heater comes off the coolant block expansion tank . No problems so far.

Talk to the folks at Sure Marine in Seattle. They sell a lot of engine heating systems, plus all the valves and exchangers you'd need. Sure Marine Service, Inc. * Since 1972 * Webasto Marine Heating, Air Conditioning, and Galley Equipment

Thanks Larry

12 volt, 20,000 BTU bus heater on ebay is about $150. Booster pump is $90. all new.

(I have read with much concern, that the water heater manufactures recommend using a non toxic antifreeze like Sierra when heated by engine coolant in case the heat exchanger within fails; they say poisonous antifreeze can get in to the domestic water supply. Is this something that anybody worries about?) Previous question, anybody got any concerns about this??

Not me. Never ever heard of anyone getting antifreeze into there water heater. It is more likely that fresh water would get into the engine from a leak, pressures being what they are. If you're paranoid you're gonna worry about it anyway. But, if the current formulated antifreeze does happen to leak "into" your water heater you will know it. You can smell even a small amount. And, if you are inclined to drink hot water (who does ?) it tastes AWFULL, cats wont even drink it anymore.

The anti-scald valve does not have to be in the shower control. There is a thermostatically controlled mix valve that can be installed on the hot water heater exit. All it does is mix in enough cold water to get the water temp down to safe levels.
Stu

It is best AT the HW heater, as a sink at 180 or so is still a danger.

There is also usually more room to work near the HE heater than in the shower room.

Many shower controls have anti-scald controls in the valve, since a secondary draw of cold water could cause scalding at the shower. If you put the scald prevention at the HW tank / heater, you don't need it everywhere. I think that's what you meant.

Stu

Here's how I connected my 3208 to the hot water heater. I tapped into the coolant line going from the oil cooler to the turbo. The coolant goes first to a valve assembly which has two shut off valves to isolate the link from the hot water heater if needed. Part of the coolant will always go across the bypass line and back to the turbo but with the shut off valves open, part of the coolant will continue on to the hot water heater passing through a zone valve and returning to the coolant line to the turbo. The zone valve is in the open position with no power to it allowing the coolant to pass. The zone valve is controlled by a Johnson controller switch which is connected to a temp sensor at the hot water heater. When the temp sensor reaches a set temp, the Johnson controller sends power to the zone valve and closes it so all the coolant bypasses the hot water heater and goes directly to the turbo. The Johnson controller and the zone valve are AC powered through the invertor. See attached photo.

I prefer normally aspirated engines myself, despite the market heading the other way.

I would be concerned that you're robbing the coolant from the turbo, which is turning in excess of 120,000 RPM under load. Make sure it gets clean oil or you'll be in the turbo market.

No robbing is taking place, all coolant meant for the turbo is getting there one way or another, even slightly cooled by passing through the cooler water in the hot water heater.