Hot Water heater tpe/placement

[Rich Harris]

All,
My Raritan hot water heater has given up the ghost. It’s a rusty leaky mess. It was located forward in the port Lazarette right above the thru-hull for a deck drain. I really do not want to put a new unit back there.
I’ve been thinking of installing one under the quarter berth. I find a 6 gallon Kuuma will fit well in one of the lockers but the reviews are less than stellar for the unit so I’m really interested in the Isotemp SPA 20, 25 or 30.
Isotemps have stainless tanks as opposed to the aluminum tank of the Kuuma and they seem to be quite a bit better made regarding quality and reliability.
I would love to hear where you all have your water heaters located, what type you have and any other feedback you can lend.
Thanks all,
Rich

• This topic was modified 4 years, 3 months ago by Rich Harris.

[typhoontye]

Hello Rich,

We have the ISOTEMP Basic. Can’t remember the exact model, but it is 6 gallons. It was originally installed by the PO in Jan ’11. Then replaced under warranty in Jan ’14. I think the reason for replacement had to do with the 120V heater element, but could be off on that.

Ours is located where your Raritan is located now. Right near the seacock for the cockpit drain in the port side lazarette. Tough to access that seacock as a consequence. The HW heater is secured to a plywood platform glassed into the boat.

The unit has been reliable, but I’ve had a heck of a time keeping it primed with engine coolant. Seems I have to burp it quite often if I want to have hot water. I’ve been through the usual culprits quite thoroughly. On my list to work on some more…

David
Blue Moon

[Patrick Haughney]

I installed an Isotherm SPA 20 about 4 years ago and have been satisfied with it both using 120V electric heating dockside and using engine heat when cruising. I installed it in the middle of three lockers under the aft cabin berth.

[Ryan Doyle]

Hi Rich,

I did this same job last spring. Ours is a different layout boat, so our water heater is behind the bulkhead aft of our nav station on the starboard side. I just replaced with the new version of the Raritan that was there as I wanted to make sure it fit and the fittings would all reconnect without hassle.

I’m pretty sure the old one lasted 20+ years.

Ryan and Kathleen
Juniper
1983 Plan C Ketch

[Rich Harris]

Patrick Haughney wrote:

I installed an Isotherm SPA 20 about 4 years ago and have been satisfied with it both using 120V electric heating dockside and using engine heat when cruising. I installed it in the middle of three lockers under the aft cabin berth.

Patrick,
Do you find the 20l capacity enough? We plan to eventually move aboard for a few year so we’re concerned with tank size but also want to be water conscious. The 20 is a better fit then the 25 (length) and the 30 is even a better fit since it’s a bigger diameter that still fits in the locker and shorter than the 20 and 25, allowing very little modification to the locker.
Thanks,
Rich

[robshookphoto]

Mine is located behind the nav station in what used to be the wet locker. The original rusted out. I replaced it with a Kuuma, and I took out the 120v element in favor of a 12v 300w element from Amazon. It’s great if you have a lot of solar.

Pearson 424 cutter - "Effie"

[Patrick Haughney]

Rich

I went with the smaller unit because I was constrained by space. Remember to include space for any plumbing you will need to fit into the locker as well the hot water heater itself. I had quite a bit of plumbing which is what limited me. I would have selected a larger size if I had more room. Having said that I have found the size to be adequate for our needs. My wife and I live aboard fulltime and it has worked well for us. We have always had hot water. I would add that we are conservative in our water usage after years of living aboard.
My heater came with a mixing valve to mix cold water with the heated water coming out of the tank. I think most tanks have this as it is considered a safety feature. The effect is that your tank can heat water to a temp hotter than acceptable for skin contact. Then mixing at the valve with cold water to lower outgoing water to an safe level results in additional volume of “hot” water. So the effective volume of heated water is somewhat more than the rated volume of the tank. This would of course apply to any tank size if it is equipped with the mixing valve.

Pat

[rdugger]

I replaced a leaky Raritan with a Superstor SS 6 gal approx 8 or so years ago. The original and current location is the middle space under the aft cabin berth. Satisfied with engine and 110v water heating.

Rick
Eclipse #73

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