WILDEN XPS4 for Pits and Sumps: Suction Lift Q&A

How high can the XPS4 lift from dry? Wilden rates the Buna-N build 04-12898 at 22.9 ft (7.0 m) dry suction lift. That is one of the better figures in the 1-1/2 inch range; the P4 manages 19 ft.

Does that mean it will lift 7 m in my pit? Not necessarily. The figure assumes water and good conditions. Thick, hot or gassy liquids, a long suction hose and a worn valve seat all eat into it. If your lift is close to the limit, we would rather you tell us the liquid and the hose length first.

What flow should I expect? The published maximum is 82 gpm (310 L/min). Wilden’s example duty is 47 gpm (178 L/min) against 2.1 bar (30 psig) discharge, with 4.1 bar (60 psig) air and about 54 Nm³/h (32 scfm).

Can it run dry while the pit empties? Like other air-operated diaphragm pumps, yes, which is a large part of why they are used for sumps. Running dry for long periods still wears the elastomers, so a level control that stops the air is worth having.

How do I tell an XPS4 from an XPS420? Look at how the pump is held together. The XPS4 is clamped and discharges vertically from the top; the XPS420 is bolted. There are 28 aluminum XPS4 builds, most commonly with Santoprene.

All 28 aluminum XPS4 builds are listed here: https://www.haquanpump.com/wilden-aodd-pumps/part-numbers?q=XPS4