Shower box

[John100156]

I agree with FP. If pipe flowback volume > float switch trigger volume then cycle. On the face of it, there are two solutions - the simple one is a box with a bigger floor area - so the volume of water required to trigger the float switch is greater; the alternative would be to fit a different float switch to increase the range over which the float switch operates (eg if it's one of those float switches with an arm, make the arm a bit longer and that would do the trick).

Cheers
Jimmy

I agree with above too. This really annoyed me on my F43 aft berth shower. I bought a new non-return valve, should have known that would be a waste of time as they always let-by in the end. So calculated volume of water in discharge pipe (PV) then compared it to cross sectional area of shower tank and difference in height of float-switch operation (TV) - of course found PV>TV.

Solution, larger tank cross sectional area, so that TV>PV. Also reduced bore of discharge pipe slightly to reduce PV and amount of water let back into the shower tank.

Mind you, if you want to minimise water left in the tank, I suppose you could always use a 12V Solenoid valve fitted into the discharge pipe and connect it in parallel with the pump motor connections. When the pump operates the valve opens, I reckon a solenoid valve would not let any water back. Just like the solenoid valve fitted to windscreen washers on some boats........

 

[Bandit]

The problem I have always had with the biscuit tin sized tupperware boxes with the screw on lids and a jabsco pump and rocker float switch inide is:

1/ is that with four hairs and a bit of congealed soap the damn float switch gets stuck down and the pump does not trip on and so the box overflows in to the bilge.

Or they

2/ The float gets stuck up when the box empties and the pump keep running when there is no water.

So I cut out the float switch and had a switch fitted in the shower compartment to turn it on and off .......Seeeemples.

 

[DavidJ]

Had exactly this problem with my Sealine S37 and put up with it for some years. My float switch failed and having problems buying a replacement bought a whole new unit, but the next volume size up......problem completely gone now.
I guess with the extra volume the amount of water coming back down the pipe isn't enough to raise the level to operate the float switch.