Collection: Submersible pumps with float switch

A pump that switches itself on and off

If the pump is left unattended — in a cellar, a crawl space, a pump sump or a garage — you want it to start by itself when the water comes and stop when it has gone. Without switching, a pump runs dry, and running dry is the quickest way to destroy one.

Three types of switching

• Mechanical float. A float on a cable. Simple and reliable, but it needs room to tip: allow for a sump of at least about 40 cm across.
• Electronic sensor. Detects water without moving parts. Works in tight spaces and switches at a lower level.
• Electrode float. Two electrodes that you set yourself, accurate to the millimetre. It does need cleaning twice a year.

A separate switch on an existing pump is also possible: see the separate float switches or the control systems. For a critical installation we also recommend a high water alarm: a pump can fail, and then you want to know before the water does damage.