Would pump valves work better pointing down?

[nfbr]

I have a couple of Whale Gulper diaphragm pumps. Had to clear one yesterday that had a bit of plastic holding the outlet valve open, preventing it sucking.

The thought occurred that with the outlet hose pointing UP, with an anti siphon loop, that any heavy particulates will settle on the valves if they can't get up the outlet loop.

If the valves pointed down, then heavy things would settle in the "sump" of the hose before going up the loop.
Not ideal, but much less likely to block valves as material tends to get pulled down by gravity.

Any thoughts / experience?

[tkeithlu]

Hmmm.

The trash falling on the discharge valve would do so when the valve was closed, and the valve only opens when pressure inside the pump is greater than pressure in the discharge hose, so it may be that trash does not get caught by the discharge valve through gravity. It would seem more likely that trash gets caught in the valve when the trash is in the discharge flow and right there part way through the valve when it closes. Long bits of trash might get caught in the intake valve when it closes, and then extend through the discharge valve when it opens and closes.

On the other hand, an imperfectly sealing discharge valve (we've all seen them) might actually suck trash from the discharge hose back into the pump. A pump above its discharge would not have that problem, because the discharge hose would drain itself. A pump below its discharge might have that problem.

A screen on the intake would prevent trash big enough to foul the pump ever getting there, but might itself be fouled to the point that the pump could not suck.

Lots of possible scenarios. In general, I'm inclined toward the suck and push of the pump as causes of fouling more than gravity.

It's engaging to think about.