Bilge Pumps

About

How Do Bilge Pumps Work? The bilge is the lowest interior area of a boat, where water from rain, spray, condensation, or minor leaks can collect. A submersible bilge pump sits in or near this area and draws in accumulated water before moving it through a discharge hose and out of the boat. Bilge pumps are designed to manage water that reaches the bilge, but they do not address the source of a leak. Unexpected or excessive water accumulation should be investigated rather than relying on the pump alone. Automatic and Switched Bilge Pumps Bilge pumps for boats can use different methods to control when the pump operates. Some models incorporate automatic switching, while others work with a separate switch or float switch. A float switch detects changes in water level and can activate the bilge pump when water rises to a specified point. As the water level falls, the switch turns the pump off. Since switching configurations vary by model, check the individual product specifications to determine whether automatic operation is built in or requires additional components. Understanding Bilge Pump GPH and Capacity Bilge pump capacity is commonly measured in gallons per hour (GPH), which indicates how much water the pump is rated to move under specified conditions. Fresh Water Systems offers Johnson bilge pumps ranging from 500 to 2200 GPH. A higher GPH rating indicates greater pumping capacity, but capacity should not be considered on its own. Boat design, discharge plumbing, installation conditions, and the intended application can all influence pump requirements and actual flow. Bilge Pump Specifications to Compare Before selecting a bilge pump, compare the specifications that affect compatibility with your boat and installation: Flow rate: Compare GPH ratings based on the pumping capacity required for the application. Voltage: Confirm that the pump is compatible with your boat's electrical system. Discharge size: Match the pump outlet with compatible discharge hose and plu