Automatic bilge pumps are important parts of any modern boat. Simply put, the bilge is the lowest compartment of a ship or boat, a hollow space below the waterline. Over time water invariably collects in the bilge. If this water isn’t removed, it can lead to the boat losing performance, or even sinking.
Bilge pumps do just what it sounds like they would: pump water out of the bilge. In contrast to old-fashioned manual pumps (or worse, a bucket and some elbow grease), automatic bilge pumps are electric devices that pump water out of the bilge as soon as it reaches a predetermined point.
How do Automatic Bilge Pumps Work?
Bilge pumps work with two main components: a pump and a float switch or liquid level sensor. The level sensor is triggered when water reaches a predetermined level; ideally this is well below the point at which it poses a genuine threat to the vessel. Once the sensor is triggered, it in turn activates the pump.
Usually, the pump works with a small impeller at the bottom that pushes the water through a vertical tube, up and over the side of the boat. (Pumping water directly out would be impractical, as the bilge’s position below the waterline would create a significant risk for leaking.)
The Importance of Reliable Float Switches
Without a reliable float switch, you run the risk of a couple of undesirable outcomes.
First – the pump might not activate when it should. This could cause the bilge water level to reach critically high levels.
Second – the pump might not turn off when the water level is sufficiently low. This could lead to the pump motor burning out, or the boat’s onboard battery running out.