Saturday, February 15, 2014

New Hot Water Heater

As mentioned in the previous post, the original Raritan hot water heater was on its last legs when we bought the boat. Over the years although it still heated water the tell-tale rust flakes and stains gave fair warning that some day it would need to be replaced. Surprisingly, even though it looked dead, it still worked when I finally unbolted it and pulled it out of the locker underneath the quarter berth as part of the re-fit/re-wiring job that I started several years ago.

One of the aspects of the hot-water heater that we wanted to change was to incorporate an engine driven heat-exchanger function. The original Raritan was a shore-power hot water heater only.

I researched manufacturers of marine water heaters and my eye was caught by the Isotherm line. I looked at the specs of their horizontally oriented units and realized that I could fit one of the 5-gallon models up in the outside part of the locker space in an area that was underutilized in the past. 

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With the measurements and fitting finalized, I fabricated some mounts for the tank out of standard issue plywood, coating them will epoxy and fit some captive stainless steel bolts.

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As part of the general cleaning and painting of the locker space I ground off paint in the area for the mounts and epoxy them into place. A first coat of Interlux Bilgekote was already applied and ready for a second coat.

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The final mounting was pretty simple. Wiring and the plumbing awaits.

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  1. Great information. Thanks for sharing such a useful and informative post.
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  2. I have never heard of this method; however, I can say that the end results are appealing. I can see that a lot of work has gone into getting hot water on board, but—as a sea lover myself—I can't imagine anything nicer than having hot water when you are on a sailboat for a long time.