Gotta get a new water heater

[Moparots]

Hello all new boat owner here, I pulled out the old rusty leaking water heater on my 36 Morgan OI. Previous owners had it set up for AC from shore power only. What is every ones opinion on new water heater brands?

The old one was not set up for a engine heat exchanger, how easy is it to install that? Hoses from the water pump? (Westerbeke 44AFour)

Can I get a water heater with the heat exchanger option and not use it? maybe hook it up at a later time.

Looked at the Kuuma, inexpensive. simple 6 gal capacity.

Just looking for every ones thoughts.

[Terra Nova]

Get one with the engine heat exchanger; it's simple to hook up. Selection boils down to what will fit in your available space, and price.

[gamayun]

I just changed mine, which was rusty and leaking. It's very easy to do. Just make sure to get the right kind of high temperature hoses. I also installed shut off valves because you'll drain the coolant if you ever need to deal with an issue on the heater side. I went with Isotemp. It's a little more expensive than other brands, but I am hoping it is sufficiently high quality that it won't break for as long as I own the boat because the sink has to be pulled to get the danged thing out of the cabinet. And I'll soon have the new countertops installed so wouldn't want to damage all that again either....

[Island Time O25]

A while ago I got a new Atwood from craiglist. Pulling out the old one and installing the new one was realtively easy and straightforward. I actually did not hook up the AC portion,just the heat exchanger to the engine, as I'm on a mooring and figured if I dock somewhere I'll use the marina shower anyway. Plus don't want to deal with AC current in general if I can avoid it.

Also Kuuma makes a temp. limiting valve which comes in handy to prevent too hot water.

[SVJennie]

I have a brand new six gallon Kuuma water heater for sale. It has the heat exchanger that does not need to be used. Let me know where you are located and I can give you a very fair price that includes shipping.

Heat exchanger hoses come off the engine come off the engine. I would be glad to walk you thru that installation.

After a number of years of usage, I expected my existing water heater would need retiring, but I was wrong - not for the first or last time.

[Valmika]

I bought the west marine brand built by Kuma I think and it works great. i replaced an old Attwood that was 16 years old. I hope the new one lasts as long. I have a Westerbeke 42B . I have attached a photo of the takeoff and return point for the water heater. It is the two hoses that are heading off to the left side of the pic. Let me know if you need anymore info

[Valmika]

Maybe this time?

[Valmika]

Whats a fella gotta do to upload a photo around here

[wrwakefield]

Originally Posted by Moparots

Hello all new boat owner here, I pulled out the old rusty leaking water heater on my 36 Morgan OI. Previous owners had it set up for AC from shore power only. What is every ones opinion on new water heater brands?

The old one was not set up for a engine heat exchanger, how easy is it to install that? Hoses from the water pump? (Westerbeke 44AFour)

Can I get a water heater with the heat exchanger option and not use it? maybe hook it up at a later time.

Looked at the Kuuma, inexpensive. simple 6 gal capacity.

Just looking for every ones thoughts.

I am preparing to do the same thing. After researching I went with an IsoTemp SPA Model [Polypropylene outer jacket vs stainle$$] for several reasons:

• Built-in mixing valve [Prevent scalding when engine heats it to 180F.]
• Super insulated [hot tank purported to last 24+ hours by other owners]
• SS tank and heat exchanger [no zincs...]
• 750 watt [1200w available] 115 or 230VAC electric element [half of the usual 1500 watt]
  True, slower to heat from electric, but less load on shore power/generator... And you can set thermostat much higher than usual e.g., 160F to take advantage of that mixing valve and get more usable hot water per charge
• Mounts Horizontally or vertically

I'll post a blog entry when I complete that project in early May.

Here is a link to Defender's listings FYI.

I hope this is helpful.

[TacomaSailor]

Originally Posted by wrwakefield

I am preparing to do the same thing. After researching I went with an IsoTemp SPA Model [Polypropylene outer jacket vs stainle$$] for several reasons:

• Built-in mixing valve [Prevent scalding when engine heats it to 180F.]
• Super insulated [hot tank purported to last 24+ hours by other owners]
• SS tank and heat exchanger [no zincs...]
• 750 watt [1200w available] 115 or 230VAC electric element [half of the usual 1500 watt]
  True, slower to heat from electric, but less load on shore power/generator... And you can set thermostat much higher than usual e.g., 160F to take advantage of that mixing valve and get more usable hot water per charge
• Mounts Horizontally or vertically

I'll post a blog entry when I complete that project in early May.

Here is a link to Defender's listings FYI.

I hope this is helpful.

I installed the same water heater (Isotherma SPA) in October 2014 to replace an a very similar Isotherm, which I installed in August 2000. The old Isotherm lasted 14 ( FOURTEEN ) years and was still functional. The 14-year old one had developed a minor leak around the 110V heater element and it was only $200 more to replace the tank than to replace the element.

We were cruising full time for four of those 14-years and lived aboard another five of the 14-years so the old Isotherm got a lot of use.

Isotherm is expensive but I consider it a fantastic deal if the current one lasts another 14-years.

[Scout 30]

Originally Posted by wrwakefield

I am preparing to do the same thing. After researching I went with an IsoTemp SPA Model [Polypropylene outer jacket vs stainle$$] for several reasons:

• Built-in mixing valve [Prevent scalding when engine heats it to 180F.]
• Super insulated [hot tank purported to last 24+ hours by other owners]
• SS tank and heat exchanger [no zincs...]
• 750 watt [1200w available] 115 or 230VAC electric element [half of the usual 1500 watt]
  True, slower to heat from electric, but less load on shore power/generator... And you can set thermostat much higher than usual e.g., 160F to take advantage of that mixing valve and get more usable hot water per charge
• Mounts Horizontally or vertically

I'll post a blog entry when I complete that project in early May.

Here is a link to Defender's listings FYI.

I hope this is helpful.

I have to second this choice. Many years ago Practical Sailor reviewed them & IsoTemp was the best rated at that time. I had a Raritan on my boat when I bought it. It was rusting out but worked great. Like an idiot I replaced it with a Stainless Seaward that looked great but is a real piece of ****. We used to be able to get to an anchorage Friday evening & still have hot water Sunday evening. Now the water's not hot Saturday morning. I'll be switching to an IsoTemp soon. FYI, Defender runs sales on them regularly.

[Terra Nova]

Scout--you might try super insulating the POS you now have, just to get some better use of it. Also add pipe insulation.

[Scout 30]

Originally Posted by Terra Nova

Scout--you might try super insulating the POS you now have, just to get some better use of it. Also add pipe insulation.

Thanks for the idea. That would be a lot cheaper. I'll give it a try.

[Cheechako]

The cheaper water heaters seem to work fine. I don't think I've had any that lasted less than 8 years (on the boat when I got it) and actually only ever had one fail... no idea how old it was...but it looked ancient.
I've never been sold on SS being worth it. Not even sure it's a good application for stainless...

[Bill Seal]

The heater on our 1982 Formosa 30 had the heat exchanger plumbed into the raw water, between the engine and exhaust elbow. (Probably the original heater). The salt water finally got to the exchanger and the aluminum hose nipple broke off. Luckily we saw the bilge pump running and my wife checked under the cabin sole. WE'RE SINKING!!!
Bypassed it, but now we have no heater when underway.
I'd like to get a replacement with a SS exchanger tube so it won't happen again. The specs on heaters all seem to prattle on about the shiny exterior, but I'm concerned about the guts.
Any suggestions?