hot water tank

Stu Jackson · Jan 19, 2016

gettinthere said:
Anyone with reports on Seaward tanks?

Our C34 skippers have vast experience with them. Our information indicates that the Seawards last anywhere from 10-15 years. When we bought our then-12 year old boat in 1998, the PO had just replaced the Seaward heater. I replaced that one in 2013.

The basic choices:

1. Kuuma - a low level copy of the basic Seaward, not highly recommended, but cheapest

2. Seaward and Raritan - middle of the line, Raritan a tad better but not $500 worth more.

3. Isotemp - great units, wonderful insulation, come with thermostatic mixing valves on the output

Your boat, your choice.

PS - If your PRV is popping, then your water is too hot. There is NO need to keep the electric working all the time; heat the water, turn the power off; it only takes about 15-20 minutes to heat the water. PRVs have been known to fail when "exercised," which is why there is no reason to do so; crud gets in and keeps it open. If you have crud, it means you heater is failing; 15 years is at the end of its useful service life.

Scott T-Bird · Jan 19, 2016

It seems that Isotemp gets better reviews than other brands AND is more economical. It sounds like a no-brainer to me.

jssailem · Jan 19, 2016

GE,
I just reviewed a variety of heaters and selected a Quick Windlass BXS2512SL. $670. Rated highly by Practical Sailor. A number of good reports by boat owners and Cruisers. The unit's water heating capacity and recovery speed let me go from a 10-15 gallon unit down to a 6.5 gal unit.
Reasons for selection.

It was a square unit and fit in the space that I am removing the water heater from 1974
316 stainless steel tank, argon welded for corrosion resistance
304 stainless steel case - could have gone with a painted or galvanized case, but the 304 stainless was only $30 and available to ship.
Heat exchanger is a thick walled (1/16"), coiled 10 ft. tube of 316 stainless steel, so it won't compromise the engine cooling system or the hot drinking water.
Insulation is 2" of high density polyurethane foam - Boat owners reported the water stayed above 120F upto 20 hours. Heat today on engine have hot water tomorrow for breakfast dishes without shore power.
All units are 1200 watts; 110 VAC - When on shore power quicker to heat your water.

We each make our compromises as we outfit our boats. My plan is this is a one and done for me as long as my hoses hold out.
Did find that the connections on this unit are British Standard Thread. Gave me a fit until I learned that the distributor supplies the connectors with the unit. My supplier was uninformed. Delayed my purchase as all the US thread fittings would not work. Once resolved all is happy.

Rich Stidger · Jan 19, 2016

I replaced my Seaward after 12-13 years. I had a leaking PT valve that I could not remove. Given that everyone said that the tank was near EOL, I just replaced. I did not spend extra for the SS exterior since the tank is in a protected place.

Scott T-Bird · Jan 19, 2016

gettinthere said:
More economical? In what way?

I think I saw the 6+ gallon Isotemps for less than $700. More economical than Raritan. Sure, Seaward tanks are lots cheaper but tanks are aluminum and galvanized steel exterior. I don't like aluminum for potable water & prefer SS over galvanized for exterior. I just bought 5.3 gal Isotemp to install in my boat. Besides, reviews seem to favor Isotemp.

Scott T-Bird · Jan 19, 2016

gettinthere said:
We dont drink out of the hot water tap.

True that ... to a greater extent maybe it's just a matter of personal preference.

Gunni · Jan 19, 2016

2003 Seaward HW heater still going strong. I would replace mine with a Seaward. These things are subject to variable water quality and disposable. Mine is effectively a thermos.

Benny17441 · Jan 19, 2016

In a scale of 1 to 3 repairing the old tank comes last and the winner is the Seaward; just think you may not own that boat in another 10 to 12 years.

Capt jgw · Jan 20, 2016

Scott T-Bird said:
True that ... to a greater extent maybe it's just a matter of personal preference.

The recommendation to never drink or cook with hot tap water applies to home systems with old soldered copper pipe, or really old lead pipes. Solder used to be made of lead, and hot water leaches the lead out faster than cold. So, drinking hot tap water could give you lead poisoning. See the news articles about Flint, MI and their water problems. Slightly corrosive water and homes with lead pipes.
Unless you have soldered fittings or lead pipes your boat, it doesn't apply.
I wouldn't trust a Chinese water heater to not have lead in it. They have a history of using lead where it shouldn't be.
Pretty much I don't trust Chinese anything.

sailnoproblem · Jan 20, 2016

Capt jgw said:
The recommendation to never drink or cook with hot tap water applies to home systems with old soldered copper pipe, or really old lead pipes. Solder used to be made of lead, and hot water leaches the lead out faster than cold. So, drinking hot tap water could give you lead poisoning. See the news articles about Flint, MI and their water problems. Slightly corrosive water and homes with lead pipes.
Unless you have soldered fittings or lead pipes your boat, it doesn't apply.
I wouldn't trust a Chinese water heater to not have lead in it. They have a history of using lead where it shouldn't be.
Pretty much I don't trust Chinese anything.

I agree with you about the Chinese manufacturing, but why would you drink hot water?

jssailem · Jan 20, 2016

You never need a hot drink and did not want to turn on the stove? Like a two hour run up the Sound into 3 ft chop with temps near 53 and the wind dead on the nose.

The motor heated water can make a great cup of beef bullion in less time than I can stop shivvering.

Ron20324 · Jan 20, 2016

[QUOTE="... , but why would you drink hot water?[/QUOTE]

What, you've never had Hot Water Soup?

Gunni · Jan 20, 2016

We keep an Aladdin SS thermos with hot potable water in the galley sink along with another for hot coffee. A boat HW heater can be contaminated with antifreeze from your engine exchange loop, bacteria, and metals and should not be considered potable.

Ralph Johnstone · Jan 20, 2016

gettinthere said:
Raritan 6 gallon hot water tank keeps overflowing out the pressure relief valve...the new raritan pressure relief valve I installed to replace the old one that I thought was defective.

The next time you you're looking at the relief valve and its leaking, open a faucet to relieve some of the pressure and see if the leakage stops.
YES? - the cool water in the tank is expanding as it heats, increasing the pressure, and the relief valve is doing it's job. Install an accumulator.
NO? - reduce the pressure setting on your water pump.
STILL DOESN'T STOP - wait for the next reply.

gettinthere said:
Raritan tech support thinks it may be sediment built up inside causing the overflow, on both engine heat AND dock power.

Scaling on the relief valve seat will cause continuous leakage at any pressure. Do I understand correctly that you have already installed a new relief valve and it also leaks ?

Capt jgw · Jan 20, 2016

Could be some crud in it. Try opening it full for a few seconds to blow the crud out. Be prepared to get wet or put a bucket under it.

Ralph Johnstone · Jan 20, 2016

gettinthere said:
Yes, I have premature ejaculation from the NEW raritan pressure relief valve, when heating water from engine or dockpower. Water pump is 35 psi and I do have an accumulator tank.

OUCH ................... I'm a little worried I could be banned from this site for even replying to your .............. ahem ............. rather colourful description of the pressure valve performance.

Mind you, a worthy comparison it is and may we assume the discharge is only periodic

and not continuous ? Aw crap, we're just getting worse here

.
Periodic discharge indicates thermal expansion of the water followed by pressure relief and is a periodic process. Any chance the accumulator could have broken diaphragm or just lost its charge ?