GL: fresh water system pumps

[Baycoaster at aol.com]

hi loopers, got a prob here.
just installed a new freshwater system on demand pump.
pump will not run constant, even with multiple spigots open.
system pressure seams to go up and down.
we have expansion tank but not sure if its doing what its suppose to.
any help /suggestions would be greatly appreciated.
den, san and flipper on m/v baycoaster



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