Are Electric Heads Supposed To Hold Water?

I have electric flush toilets in my boat. The guest head, between flushes, will slowly drain to empty. This is also the "stinky head" (the whole boat though has an odor when first opened up). The master head, which I rarely use, holds water like I would think any normal toilet would (and no smell).

Searching online yield few specific hits except one from Peggy saying they don't hold water and a couple other owners saying they do, which isn't helpful [emoji53]

If it isn't supposed to hold water, what prevents having an open line to the holding tank gassing out into the boat?

If it is, what do I need to look at fixing?

Thanks!

Mine do not hold water, if you want them to hold water elevate the discharge hose to the desired height.

Mine do not hold water. We had a bad smell when we bought the boat. The forward head had a bad joker valve in it. Simple, if somewhat nasty fix.

The Sixty four dollar question?, I would think the answer as to holding water or not (visible in the bowl) would depend on:

1) The height of the intake hoses and out let hoses
2) Do they have vented loops in both lines
3) Are the vented loops free and clear and not blocked(when were they checked last?)
4) The general hose lay out/routing, correct angles,any loops etc,
5) Are the toilet non -return valves closing(these quite often get clogged with calcium build up which then allows water into the bowl)

In a normal system you will get a little water returning from the vented loop lines (all though there are non return valves to supposedly stop water from flowing back into the bowl) but water should still be present in the line to stop the gas/smell coming through the bowl ,

Cheers Steve

Ours are not designed to hold water -- per the Jabsco guy I spoke with several times a few weeks ago -- but they CAN if you want them to. Ours usually does, the amount being determined by whomever flushed last. If you really do want them to hold water, a vented loop will do it (and the Jabsco guy told me their part number for that). We don't have a vented loop, but apparently our discharge loop is high enough and the system is ventilated well enough so the additional vent in the loop isn't necessary.

That said, ours was suddenly NOT holding water (hence my discussion with Paul), and it turned out the symptom was likely caused by a siphon coming into effect because of a hard clog that had developed in our system while I had it open for several days. Probably the scale dried out, got to the point where the system wouldn't really flush... but the siphon would eventually empty the bowl.

Anyway, our solution for that particular problem was a few doses of Barnacle Buster (I had on hand), following the Sew Clean dilution instructions. Mentioned all that in a recent thread...

The joker valve is what's supposed to keep holding tank odor from coming back into the boat.

-Chris

Ours hold water, but it depends. If hosing goes up it will (with good or bad joker valve), if hosing goes down it wont (even with good joker valve).