When a backup is worth asking about
- Your power has gone out during storms
- Your basement has taken on water before
- The basement is finished or holds things you want to keep dry
- You are away from home for days at a time
How a battery backup works
A battery backup system adds a second pump, set a little higher in the pit than the main pump, with a battery and a controller. If the water rises past the main pump's level, because the power is out or the main pump has failed, the backup pump can start. Some systems include an alarm.
Its limits
A battery can only run a pump for a limited time, and that time depends on the battery, the pump and how much water is coming in. A backup pump may also move less water than the main pump, and batteries need checking and replacing as they age. Ask the plumber how the system you are considering is expected to perform.
Water-powered backups
Some backups run on municipal water pressure instead of a battery. Whether one suits your home depends on your water supply and local rules. Because they rely on water pressure, ask about them carefully if your home is on a private well.
Questions to ask the plumber
- How long is this system designed to run on battery?
- Does my pit have room for a second pump and its check valve?
- Does it include a high-water alarm?
- How do I test it, and how often should the battery be checked or replaced?
- Would a water-powered backup suit my home instead?
Questions
Do I need a battery backup sump pump?
It can be worth considering if your power goes out in storms, your basement has flooded before or you store things you value down there.
How long does a backup battery last?
It depends on the battery, the pump and how much water comes in. Ask the plumber about the specific system and how to check it.
Can a backup be added to my existing pump?
A backup may be able to go alongside an existing pump, depending on the pit and the setup. A plumber can help confirm.