electric marine hot water heaters
 

Well,

Finally sold the old boat, and have now devoted my spare time to preparing
my new project boat for launch into the remainder of the Ohio summer.

As my first order of business, I hooked in shore power and started up systems.
Refrigerator? Check. Stove? Check. Outlets? Check.

I then turned on the water pressure and ran the antifreeze out of the
lines. I then started filling the tank (while still running the
faucets). Once the tank was filled. I turned on the hot water tank,
which immediately tripped the main breaker. I noticed the polarity
indicator, flashed before tripping the main. Tried several times with all
other systems powered off. Same results.

Any ideas? Never having a hot water system, am I overlooking something
obvious? Does this system need to be bled or reset at the water heater?
Could it be the polarity of the power, even though everything else was
working, and the polarity light does not flash until the tank is turned
on?

Any help or suggestions will be appreciated.

Bob Dimond

electric marine hot water heaters
 

Electric elements do "rot out" and expose the nichrome wire to the water. The
grounding/bonding will cause the breaker to trip if you have a lot of minerals
in the water. I would suggest removing them and giving them a quick look. If
they show signs of cracks or corrosion, replace them. They are cheap.
This can be exacerbated by buildup of those minerals at the bottom of the tank.
If the bottom element can't "breathe" it will quickly burn out and there is
plenty there to short it to the tank.
I have a piece of 1/2" CPVC rigged up to fit on my wet/dry vac to suck this
stuff out.

OT ... has anyone used engine heat, via a double isolation heat exchanger to
heat water? That sounds like a "free" way to do it if you are running.

electric marine hot water heaters
 

On 14 Jun 2004 16:34:50 GMT, (Greg) wrote:

OT ... has anyone used engine heat, via a double isolation heat exchanger to
heat water? That sounds like a "free" way to do it if you are running.

=================================================

Not sure what you mean by a double isolation heat exchanger but most
marine hot water heaters have an internal coil for circulating engine
coolant and the heating water. It's very common if that is what you
meant.

electric marine hot water heaters
 

Not sure what you mean by a double isolation heat exchanger

A double isolation exchanger is one with an intermediate fluid between the
potable water and the heating water. That way a single failure will not
contaminate your water. It is usually used any time the heating fluid is a
glycol mix.

electric marine hot water heaters
 

On 14 Jun 2004 19:47:36 GMT, (Greg) wrote:

A double isolation exchanger is one with an intermediate fluid between the
potable water and the heating water. That way a single failure will not
contaminate your water. It is usually used any time the heating fluid is a
glycol mix.
===================================

Assuming you don't drink the hot water, a simple check valve in the
cold water supply line will suffice. I've never seen a boat with the
arrangement you describe, but anythings possible I suppose.

electric marine hot water heaters
 

I think these systems are primarily in sailboats, to have hot water for
dishes and showers while at anchorage. Just like refrigerators that run
off of an engine mounted compressor.

Bob Dimond


In article , Wayne.B
wrote:

On 14 Jun 2004 19:47:36 GMT, (Greg) wrote:

A double isolation exchanger is one with an intermediate fluid between the
potable water and the heating water. That way a single failure will not
contaminate your water. It is usually used any time the heating fluid is a
glycol mix.
===================================

Assuming you don't drink the hot water, a simple check valve in the
cold water supply line will suffice. I've never seen a boat with the
arrangement you describe, but anythings possible I suppose.

electric marine hot water heaters
 

I think these systems are primarily in sailboats, to have hot water for
dishes and showers while at anchorage. Just like refrigerators that run
off of an engine mounted compressor.

Bob Dimond

Most marine water heaters can work with either electricity or the circulation
of engine coolant through a coil. Has nothing to do with sail vs power. Heating
the water
with engine coolant means you can have hot water underway without running a
generator.

electric marine hot water heaters
 

Okay. Is it really necessary to distinguish this point? IMHO the point
was adequately made that one need not be tied to shore power. Sheesh.

Bob Dimond


In article ,
(Gould 0738) wrote:

I think these systems are primarily in sailboats, to have hot water for
dishes and showers while at anchorage. Just like refrigerators that run
off of an engine mounted compressor.

Bob Dimond

Most marine water heaters can work with either electricity or the circulation
of engine coolant through a coil. Has nothing to do with sail vs power.
Heating
the water
with engine coolant means you can have hot water underway without running a
generator.

electric marine hot water heaters
 

Okay. Is it really necessary to distinguish this point? IMHO the point
was adequately made that one need not be tied to shore power. Sheesh.

Bob Dimond

?????????

Are we having the same discussion?

I thought you posted that hot water heaters
that circulated engine coolant through a coil to warm up the hot water were
found primarily on sail boats.

I correct that erroneous idea and you wind up "sheeshing"?

What's with that?

You said:

I think these systems are primarily in sailboats, to have hot water for
dishes and showers while at anchorage.

How did I misread that?

electric marine hot water heaters
 

Sorry, Gould. Bad day. Still, my point is made. The idea is that heat
exchangers are to allow use of the system when the boat is not tied to
shore power.

Perhaps this prevelance is influenced by geography, but I've seen this
type of system on more sailboats than powerboats of comparable size.
These observations support my statement that this setup is more prevelant
in sailboats. Sailboats are more likely to be underway for longer
periods of time and are more likely to be anchoring without ammenities.
Add to that my statement was in response to a powerboater who has never
heard of such a system and it supports my viewpoint...

You point out the obvious that these can be used on powerboats as well.
Your personal observations may disagree with my statement that the system
is more prevelant among sailboats, but your just picking nits.

Bob Dimond