holding tank height above the head?

[Chris]

Peggy,I have followed your advise and read all the articles in this forum plus found (all of a sudden, when I know what to search for) a lot more on the net, so I know a lot more now thanks to your advice. I think by now I know how I want to plan the two heads in our boat. One question remains though, "is there any practical not to exceed height, to place the holding tank above the head itself"? Can the pumps on the market pump out and empty the hose when the head content is pumped upwards?I was thinking, as I have space behind both heads, to place the holding tanks well above the waterline, to be able (if the pumps malfunction) to have gravity fall to empty the tanks, is it a bad idea?Chris.

 

[Peggie Hall/Head Mistress]

Tanks can be above toilet, but...

Unless you want anything in the hoses that doesn't make it to the tank to run back into the bowl, there should be a loop (not necessarily vented, but vented can't hurt) immediately after the toilet that's even higher than the inlet in the tank. Whatever is in the hose between the toilet discharge and the top of the loop can still run back down into the bowl, but 1-2' of hose holds a lot less than 6-8', and what's left is far more likely to be only clean flush water.

 

[Chris]

Learning curve is rising

Thanks Peggy, due to your tips and comments I have avoided unecessary complicated installations which I was adviced to do from some "experts". Well they wanted to sell their products of course.All the best, Chris.