I just finished a new holding tank installation. I have two
independent, top mounted lines to empty the tank. One to the deck pump
out and one to a Sealand T 12 Bellows pump. This pump is bullet proof
, easy to service and can run dry forever.

I made a couple of plumbing modifications to make servicing the system
easier.

1. where possible, I used PVC
2. I used Sealand barbless connectors everywhere.
3. All connections at the tank were made with cleanout tee's. Simply
remove the plug and push a rod down to clear any blockage. No need to
remove the hoses.
4. Put a tee and plug in front of the pump so antifreeze can be
introduced there instead of filling up the tank.
5. All hoses are pitched so there is no standing water in any hose.
6. Since the Sealand pump has one way valves and the thruhull is only
opened to discharge the tank, there is no high loop in the discharge
line.
7. Added a high loop to the toilet flush water line between the hand
pump and the bowl.






On Fri, 23 Apr 2004 00:59:07 GMT, Dick Locke
wrote:

I have what I think is overkill on my holding tank pumpout setup but I
want to check to see if anyone has experience saying it's a good idea.

The holding tank has three pumpout lines. One to the deck for the
shore-based vacuum pumpout, one to an electric macerator pump, and a
third that goes to the manual bilge pump via a y-valve. The manual
bilge pump can be directed to pump from the bilge or from the holding
tank.

I had a small leak in the third pumpout line where it connects to the
y-valve. Rather than trouble-shoot why sewage is in that line, I'm
inclined to simply remove it. I hate to see the manual bilge pump
complicated with y-valves, it would take some extraordinary
circumstances to make me want to run sewage through bilge pump lines
that aren't designed for it, and I can carry a spare macerator pump.

Has anyone been in circumstances where they found this setup valuable,
or where they wished they had this setup?