Richard:

Can you share with the forum the make and model of the on demand pump(s) that you used for the fresh water system?

I used a March submersible magnetic coupled impeller pump, 230 volt 50/60 hertz like this

http://www.marchpump.com/lc-3cp-md/

for the sea water for the 4th Air Conditioning unit that I installed in the galley. It is quiet, maintenance free, has no seals to wear out or leak etc. The only down side was it was a bit expensive at US$585.00. They make various sizes but this one met the specifications for the Climma Compact 10 AC unit I installed. I could have used the excess sea water from the Calpeda pump used for all the other AC units but I wanted a separate pump for redundancy.

Ray Eaton (Joel's Amel guru in Ft. Lauderdale, now deceased) changed my sea water anchor wash-down pump to a fresh water system using piggy backed Jabsco on demand pumps. I now use that system to wash the entire boat while at anchor. Unfortunately I don't know the model numbers of those pumps. It has been a great asset tot he boat.

Gary