Originally Posted by Hit'the'road
I got a macerating pump to use when emptying the black water tank. ...... Does anyone have a good idea how to wire this in?.....
This is what I did on the 345 - I mounted a "Blue Seas Systems" switch (West Marine) in the utilities bay. Installed a fuse in the 12 volt
I had previously ran a 4 gauge breaker protected wire from the house batteries to the rear of the unit. - Make sure you do a voltage drop analysis on the guage of wire and the length of the wire run for the amperage your pump will pull.
When dumping - Pump out (dump) the black tank first, then equalize the gray water into the black tank, close the gray water tank valve, pump out the black tank again. Equalize the grey and black tanks again, close the grey valve again, and pump out the black tank. Equalize the grey and black tanks one more time, close off the black tank, pump out entirely the grey tank.
By leaving a few gallons of water in the black tank you have a better chance of keeping all of the residual solids in solution, and prevent a build of of dry solids on the walls of the black tank.
Also, by keeping the "water charge" in the black tank you minimize the possibility of the dreaded "brown solids mountain" accumulating in the black tank - the "Brown Mountain" is no fun to deal with - guess how I know.
From now on, I always keep a few gallons of water in the black tank.