Sump Pump - Backup Components

Backup Components

A secondary, typically battery-powered sump pump can operate if the first pump fails. A battery powered secondary pump requires the following components in parallel with the above others:

• A battery-driven 12 volt sump pump with its own water level sensor, piping, and check valve (the pipes usually join after the check valves to prevent reverse flow through the primary when the secondary unit is pumping);
• It must be a marine deep cycle battery, or special long-life standby battery. Standard automobile batteries are not suitable for this application. Auto batteries are designed to deliver a high current for a short period. Sump pumps need a smaller current for a long time.
• A trickle-charge battery charger. May alternately have a specialized controller to manage, monitor and test that the battery holding a charge.

Alternative sump pump systems can be driven by municipal water pressure. Water-powered sump pumps are similar to backup battery-driven systems with a separate pump, float and check valves. One can also use an ejector pump that uses an ordinary garden hose to supply high pressure water and another garden hose to carry the water away. Although such ejector pumps waste water and are relatively inefficient, they have the advantage of having no moving parts and offer the utmost in reliability.

If the backup sump system is rarely used, a component failure may not be noticed, and the system may fail when needed. Some battery control units test the system periodically and alert on failed electrical components.

A simple, battery-powered water alarm can be hung a short distance below the top of the sump to sound an alarm should the water level rise too high.