The entry in brief
Test the pump by pouring water into the pit until it switches on, check that water leaves the house through the discharge line, keep that line clear of snow and debris, clean the pit once a year and test any backup system as well. Most of this takes a few minutes each season and requires no tools beyond a bucket.
What is going on
Many Mississauga homes sit on clay soil that holds water. Weeping tile around the foundation collects groundwater and sends it to the sump pit, and the pump lifts it out and away from the house. Spring thaw and summer thunderstorms put the most strain on the system. Pumps fail for simple reasons: a float that sticks, a clogged intake, a frozen discharge or a power outage during the very storm that floods the pit. Regular checks catch most of these before they matter.
In order
Every season
- Ease a bucketful into the pit: watch the float rise, the motor should run, and it should stop once the pit is low.
- Go outside and confirm water comes out of the discharge and flows away from the foundation.
- Grinding or a rattle means a worn impeller or a stone in the works.
- Make sure the plug sits in a live outlet and the cord is not cracked.
Once a year
- With the power off, lift the pump out if you can do so safely.
- Clean the intake screen and remove silt or gravel from the bottom of the pit.
- Inspect the check valve for leaks or sticking.
- To try the backup, pull the main pump's plug and fill the pit by hose.
Before winter
Make sure the outdoor discharge drains freely and will not freeze solid. A discharge buried in snow or frozen shut can force water back into the pit.
Slips to avoid
- Running the discharge into a floor drain or the sanitary sewer, which is not permitted and can overload the system.
- Letting the float rest against the pit wall where it can jam.
- Forgetting the backup battery for years.
- Covering the pit with stored boxes so no one checks it.
- Ignoring a pump that runs constantly; something is wrong.
When the ledger says phone
Call if the pump hums without pumping, cycles every minute, trips a breaker, leaks at the check valve or cannot keep up during a storm. Pumps that are old and noisy may be near the end of their service. Our pages on sump pump repair and sump pump installation explain the work. For sewage coming up through a floor drain rather than groundwater, read about backwater valve care. And if you are finishing the basement, plan the sump access properly; our bathroom renovation plumbing page discusses working around it.
What callers want to know
What is a sump pump's working life?
It depends on how hard it works and the model. Regular testing tells you more than age alone.
Do I need a battery backup?
If a power outage during a storm would flood your basement, a backup is worth serious thought.