Test yearly, before wet season
Test it at least once a year, timed before your wet season, and more often if it runs frequently or you are in a high-water-table area. The real test is pouring water into the pit and confirming the pump switches on, clears it, and shuts off cleanly.
A sump pump sits idle in a pit doing nothing until the one day it has to move a lot of water fast, often during a storm when the power is flickering. That is exactly the scenario where an untested pump reveals it has been dead for months, and the cost is a flooded basement and mold.
The annual test is worth doing right: not just eyeballing it, but pouring water in and watching it kick on, clear the pit, and shut off. If you have a battery backup, test that too, because grid power is the first thing to go in the storm you are protecting against.
How to do it
- Confirm the pump is upright in the pit, plugged into a working outlet, and that its breaker has not tripped.
- Check that the float switch moves freely and is not snagged on the cord, the pit wall, or debris. A stuck float is a top failure cause.
- Unplug the pump and clean the pit, removing debris and sludge around the inlet.
- Inspect the inlet screen, check valve, and discharge connections for corrosion or wear, and replace worn parts.
- Confirm the check valve on the discharge line is intact and oriented correctly so the pump is not re-pumping the same water.
- Confirm the discharge pipe is clear and sends water at least several feet from the foundation, not back toward the house.
- Plug the pump back in and slowly pour a bucket of water into the pit until the float triggers. It should switch on promptly, empty the pit, and shut off.
- If it has a battery backup, cut the main power and repeat the water test to confirm the backup takes over.
Common mistakes
- Never testing it between storms, so you discover the failure during the flood.
- Reaching into an energized pit by hand. Unplug it first, or use a non-conductive tool to move the float.
- Discharging the water too close to the foundation, where it seeps back into the pit and overworks the pump.
This is exactly the kind of thing that is easy to know and easy to forget. Adulting can put it on a cadence so it surfaces when it is next due, instead of when something goes wrong. Free to start.
Sources
Questions people ask
- Why test before the wet season specifically?
- Because that is when you need it and when power is most likely to be out. A pump that failed silently months ago only reveals itself when the water is already rising, which is the worst time to find out.
- How long does a sump pump last?
- Commonly around 10 years as a general rule of thumb, though that is trade practice rather than a fixed standard. If yours is past seven to ten years, factor that into your testing and budget for a replacement.