I think these systems are primarily in sailboats, to have hot water for
dishes and showers while at anchorage. Just like refrigerators that run
off of an engine mounted compressor.

Bob Dimond


In article , Wayne.B
wrote:

On 14 Jun 2004 19:47:36 GMT, (Greg) wrote:

A double isolation exchanger is one with an intermediate fluid between the
potable water and the heating water. That way a single failure will not
contaminate your water. It is usually used any time the heating fluid is a
glycol mix.
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Assuming you don't drink the hot water, a simple check valve in the
cold water supply line will suffice. I've never seen a boat with the
arrangement you describe, but anythings possible I suppose.