# Water Heater



## galernikus (Oct 25, 2008)

Hello everyone,

I have a an old Raritan 6 gallon water heater on my Seidelmann 299. I want to replace it with new heater that has a heat exchanger so I can hook it up to my Yanmar engine. Initially I looked with at the Raritan, but I also looked at some cheaper "squre models" such as Kuuma.(Defender.com)
It's half the price of the Raritan... Is the quality making up the price difference? Also, because it's a square shape instead of cylindrical, does it make it withstand less pressure? Thank you and GO VOTE.


----------



## sailingdog (Mar 19, 2006)

The amount of pressure on a boat's water system isn't that high, so the shape of the tank shouldn't be an issue. Some of the price difference is paying for the brand name Raritan... some of it is probably in the quality of the product.


----------



## christyleigh (Dec 17, 2001)

sailingdog said:


> The amount of pressure on a boat's water system isn't that high, so the shape of the tank shouldn't be an issue.


.... But the rated PSI of the Pressure Relief Valve can be. I replaced the water pump that feeds my Isotemp water heater which from the obscene prices of the Isotemp I saw when I had my issue must put it at the 'top of the line'. As long as you don't do what I did... which was blindly or dumbly if you wish, just pick out the 'best' / highest PSI pump I could find without checking the 'fine print' in the water heater manual for the Max PSI allowed. I don't remember the exact numbers off hand but it was something like - Water Heater max allowed PSI was 47 and I fed it with a 50 + PSI pump. The relief valve handled it for a while summer before last but then it started 'hammering' - release-hold-release-hold into the drain hose making a horrible racket. Looking back on all the things that went on that spring I think the valve 'took it' for a while because I had a very small slit in a hose elsewhere that finally blew. After that there was no stopping the hammering until I read the fine print in the manual ...... duh.... and re-replaced the pump with a 45 PSI pump. Problem solved.


----------



## Maine Sail (Jan 6, 2003)

*Water Heaters*

There are basically only a few marine HX/Electric water heaters made.

*Atwood, Force Ten (Kuumha) & Seaward's -* These square water heaters look to be all made by the same company and re-badged. They all feature a stainless steel JACKET but an ALUMINUM tank! Buyer beware!

At a minimum this is cheesy and misleading. Think about it, you have steel, aluminum, stainless, brass and perhaps copper in your HX/engine/domestic water circuit. Aluminum is the LEAST noble of these metals..!!! I would not pay big bucks for these corner cutting, inferior products if you value your dollar! I have had one fail on just about every Catalina I owned..!!

*Superstor *- Superstor's are made by Heat Transfer Products a REAL water heater company who also sells water heaters to plumbing and heating wholesalers and to the trade under the Superstor brand name. They also private label some tanks for manufacturers of boilers & heating equipment so they can offer a matched set. The tanks are 100% 316 STAINLESS thought the HX is made of "cupronickel" which is just a coated copper coil. They have had some issues with HX's on some residential "indirect fired tanks" in the past but those issues seem to be behind them.

*Isotemp/Isotherm -* These tanks are very well built tanks and also made of 100% 316 STAINLESS. The HX, jacket and tank are ALL 100% stainless (no dissimilar metals other than the electric heating element). Isotemp water heaters are made in Italy and are manufactured under the Indel/Webasto umbrella. By a decent margin, and in my opinion (opinion based on 13 years spent as an independent manufacturers rep the hydronics industry selling this type of product) these are some of the best built marine electric/HX water heaters made and NO I don't yet own one but will WHEN not IF mine fails I will..

*Quick -* This is an interesting new Canadian made tank with a plastic or 304 stainless jacket and a 316 internal tank and HX. Don't really know much about them and distribution is limited. Quick is a decent company to deal with for windlasses and such so they would probably stand behind the product.

*Torrid -* This Seattle based company produces a glass lined tank with a tin plated copper HX and powder coated STEEL jacket! If you know what's good for you DO NOT buy a steel jacketed anything that will sit in a damp bilge!

*Raritan -* This round water heater features a rust resistant plastic jacket but a STEEL glass lined tank similar to the Torrid. Glass lined tanks don't last well in the residential world so why would they last in the marine environment? 316 Stainless will out last a steel glass lined tank every day of the week..

There are other tanks out there such as the Vetus "tank within a tank design" but the list above are the most commonly sold & used. There ARE differences in water heaters. The Superstors & Isotemps are worth the money! The "square" tanks are not...


----------



## sailingdog (Mar 19, 2006)

So, basically, you're saying get an Isotherm/Isotemp if you have to buy one. If you can't get an Isotherm/Isotemp, get a Superstor.  Thanks for the heads up and summary Mainesail.


----------



## bhcva (Feb 11, 2007)

*atwood is hanging in there*

They may not be making them today as they did 14-15 years ago, but mine of that vintage has had no problems. YMMV. It is not located in the bilge, but under the rear quarter bunk.

Bruce


----------



## T37SOLARE (Feb 1, 2008)

*QL marine - Volvo Penta*

SOLARE came with a new QL Water heater installed by the PO. I'm quite impressed with it as it provides almost instant hot water on shore power (15 minutes or less) and it keeps the water hot for well over a day.












> The QL water heater is available in 20, 22, 30, 40 and 60 L (5-16 gallons) sizes. The tank is made completely in acid resistant stainless steel, which makes it very suitable for the marine environment. The design and materials also meet the highest sanitary requirements. The QL water heaters are insulated using polyurethane foam, a material that contains a lot of air and thus reduces heat dissipation. The insulation is extra thick on the upper panel and helps keep the water hot long after it has been heated. Thanks to the QL water heaters innovative compact plastic casing and integrated brackets these units occupy less space than equivalent cylindrical models with separate fastening brackets. They also feature greater security, like five sturdy fixing points with no sharp edges.
> 
> QL is using electric heating elements in incoloy which have a much longer life compared to copper and have the great advantage of not being damaged if switched on electrically without any water in the tank.


qlmarine.com


----------



## galernikus (Oct 25, 2008)

Thank you for all the reply's. My decision seems easy now


----------



## Maine Sail (Jan 6, 2003)

T37SOLARE said:


> SOLARE came with a new QL Water heater installed by the PO. I'm quite impressed with it as it provides almost instant hot water on shore power (15 minutes or less) and it keeps the water hot for well over a day.
> 
> 
> 
> ...


Can the QL be heated by your engine? Meaning does it have a HX coil inside the tank that your engine cooling system runs through to heat the water when away from the dock?

None of the info on the web site seems to say it can be used in this fashion?


----------



## tdw (Oct 2, 2006)

One of the boats at our yard was having a QL fitted recently.

Is yours still going, how do like it after this time ?

They look pretty good to me, like the size and shape.

ps - Maine...you asked if they run off engine and I believe the answer is yes.



T37SOLARE said:


> SOLARE came with a new QL Water heater installed by the PO. I'm quite impressed with it as it provides almost instant hot water on shore power (15 minutes or less) and it keeps the water hot for well over a day.
> 
> 
> 
> ...


----------



## akavishon (Apr 29, 2007)

My old Atwood finally died an ungraceful death, and the replacement short list is a) Isotherm; b) SuperStor; c) Volvo/QL

I've read lots of raving comments on Isotherm, less on SuperStor, and none on Volvo/QL. Does anyone have any experience with this product? It looks great to me, but how does it do in the real world?

TIA, Zoran


----------



## Trader Jack (May 24, 2015)

I have just swapped out my old 15 yr old Seaward. I opened it up and the cyclinder was aluminium and looked as new as the day it was made. I got a square kuuma due to space and price. Nothing wrong with tigg welded aluminium. Selling my old one second hand in perfect working order.


----------



## mitiempo (Sep 19, 2008)

Trader Jack said:


> I have just swapped out my old 15 yr old Seaward. I opened it up and the cyclinder was aluminium and looked as new as the day it was made. I got a square kuuma due to space and price. Nothing wrong with tigg welded aluminium. Selling my old one second hand in perfect working order.


Unfortunately the Kuuma has no option for a magnesium anode. It is a copy of the Seaward but not as well built.


----------



## seaner97 (May 15, 2011)

MaineSail, any updates on Quick?


----------



## Minnewaska (Feb 21, 2010)

I'm not familiar with the broad spectrum of hot water tanks, but having a user replaceable heating element is absolutely critical. The do burn out eventually, but rarely, and they can die a wrongful death, if you empty your water and run the tank dry.


----------



## seaner97 (May 15, 2011)

For those of us that will nearly never use anything other than the exchanger, I'm less concerned about the element than I am MaineSail's updated experience.


----------



## seaner97 (May 15, 2011)

Hoping as MaineSail is on line, he may take a second to update his experience with quick


----------



## Maine Sail (Jan 6, 2003)

seaner97 said:


> Hoping as MaineSail is on line, he may take a second to update his experience with quick


No not me. Have not seen one installed and I generaly install the Isotemp unless an owner wants a like for like replacement of a lower quality unit.. BTW the excellent Super Stor has been discontinued... Apparently few are willing to pay for a quality water heater...?


----------



## albrazzi (Oct 15, 2014)

My WH was tied to the engine (RWC) but failed to heat the water that way so I disconnected that circuit and only use the electric portion works fine on shore power. May be the fault of the RWC temps but I like the simpler system and didn't want the cooling water running around inside the boat.
Gotta check my brand after Maine's post.


----------

