Want hot water to shower and galley sink direct from engine

[grewvin1]

Wellcraft, 1987, twin 5.7L. want to run line off of engine to run hot water to shower and sink taps. Is there a site for this or a kit. Where to take water off and is a return line needed for when hot water not being used?

 

[Bondo]

Re: Want hot water to showe and galley sink direct from engine

Re: Want hot water to showe and galley sink direct from engine

Wellcraft, 1987, twin 5.7L. want to run line off of engine to run hot water to shower and sink taps. Is there a site for this or a kit. Where to take water off and is a return line needed for when hot water not being used?

Ayuh,... Are the motors raw water cooled, or closed coolin',..??

If raw water cooled, you can tap off the T-stat housing, but I donno's you'd get much pressure, nor volume...

More often, a water heater is used, 'n heat/water from the motor is returned to the motor, 'n the domestic water is pumped independently...

 

[RotaryRacer]

Re: Want hot water to showe and galley sink direct from engine

Re: Want hot water to showe and galley sink direct from engine

The best way to do it is with a water heater with a heat exchanger. Basically the hot water from the engine is routed through a heat exchanger in the water heater and heats the water already in the tank.

SEAWARD PRODUCTS 120V AC Water Heaters with Heat Exchanger at West Marine

 

[agallant80]

Re: Want hot water to showe and galley sink direct from engine

Re: Want hot water to showe and galley sink direct from engine

This is a PITA unless you have a closed cooling system on your motor that you can tap in to and replace your hot water heater with one that has an exchange unit. You will mess up the heater with an exchange unit if you run raw water through it.

 

[RotaryRacer]

Re: Want hot water to showe and galley sink direct from engine

Re: Want hot water to showe and galley sink direct from engine

He's in Georgian bay. Fresh water. Corrosion can happen, but not nearly as bad as salt water.

The Seaward product was just one example. And with an aluminum heat exchanger I would hesitate also.

Here is a company that uses all stainless construction: Quick Water Heaters 3.9 Gal-20.8 Gal Stainless water heaters with exchangers 3 year warranty

 

[JoLin]

Re: Want hot water to showe and galley sink direct from engine

Re: Want hot water to showe and galley sink direct from engine

I factor the cost of a new 6-gallon heater ($300-350) every 5 years into my operating costs. That's about how long it'll last on a RWC engine in salt water. Replacement is a good opportunity to change out hoses and fittings, too. In fresh, the annual 'set-aside' $$ will be a lot less. I wouldn't spring for a stainless $600+ heater, but that's me.

My .02

 

[Thalasso]

Re: Want hot water to shower and galley sink direct from engine

Look up top and in the search. type in hot water tank. Iboats sells them as good a price as anyone else. I think you will like the Attwood tanks.

 

[trevtt600]

Re: Want hot water to shower and galley sink direct from engine

I had a water heater hooked up to my port motor on my Wellcraft. My cooling hose that ran from the water pump to the thermostat housing had a brass "T" in it. One line went from this brass tee to the water heater. Then another line was ran from the back/bottom of the thermostat housing to another line in the heater. Ill try to drawn up a diagram for you. I ended up removing the heater since I don't feel it is need in Norfolk here, and mine was rusted beyond use.

Top hose was pulled off of the bottom of thermostat housing. There should be a plug there. I am not 100% sure this is the water flow pattern, but im pretty sure, or else it would be getting cold water instead of the hot water that has been ran through the motor already.

 

[MarkSee]

Re: Want hot water to shower and galley sink direct from engine

...mine was rusted beyond use.....
...this is the water flow pattern, but im pretty sure....

Your picture/diagram is how it is on my Sea Ray which is correct.

When I had the survey done before buying the Sea Ray we found the 2 hoses just laying by the heater with the fittings broken off part in the hose and part in the heater. We guessed from serious salt water corrosion--nothing was leaking though with the boat running.

That was an Attwood tank as Thalasso pointed out so a new one was purchased and has been working fine for 2+ years now.

The cost was just under $300 but what a PITA to replace; at least on my boat. The batteries sit right in front of it and had to come out; the fresh water pump sits on a board on top of the tank had to come out; of course all the plumbing had to get disconnected and moved out of the way.

As my boat is completely raw water cooled, occasionally I do use Salt Away to flush through the engine once it's warmed up so hopefully that is getting run through the hot water heater also and might help it last a little longer.

But I am now wondering if I could put in some fittings in the hoses right before/after the heater to where I could hook a garden hose and flush fresh water and Salt Away through the heater only when the boat is not running.

Mark

 

[JoLin]

Re: Want hot water to shower and galley sink direct from engine

But I am now wondering if I could put in some fittings in the hoses right before/after the heater to where I could hook a garden hose and flush fresh water and Salt Away through the heater only when the boat is not running.
Mark

You got me thinking (dangerous). That actually shouldn't be too hard, with a valve and garden hose bib in the heater's 'inflow' hose, and a valve and extension in the 'outflow' hose. You could potentially bypass the engine and direct the outflow right over the gunnel into the water. I can't picture the whole setup just sitting here, but it seems do-able.

My .02