You want to know your sump pump will start the next time rain or snowmelt fills the pit. You can check in about five minutes with a bucket of water. How the pump behaves tells you whether it is fine, needs a simple check, or needs a plumber.
TL;DR
- Do a full test at least once a year, before the spring thaw, and check the pump during and after heavy rain, snowmelt and power outages.
- For most home sump pumps, the bucket test is the most reliable check: pour water into the pit and watch the pump start, empty it and stop.
- Testing without water only works on some pedestal pumps, and only if the owner's manual says how. When in doubt, use the bucket test.
- Watch, listen, and check outside. The pump should start on its own, lower the water quickly, stop cleanly and send water out of the discharge pipe.
- Test a battery backup separately, two to five times a year, following its manual.
- If the pump fails, check the plug and breaker from a dry spot. Anything beyond that is a job for a plumber.
How often should you test a sump pump?
Test it fully at least once a year, and check it whenever the weather puts it to work. The Government of Canada's sump pump guidance recommends a yearly test with water and checks during and after rain, snowmelt and power outages. It also says to test a backup pump two to five times a year.
In Burlington, Oakville and Hamilton, the best time for the yearly test is late winter, before the spring thaw. Also test a pump that sat idle through a dry summer. A float can stick, and a motor that has not run for months may not start.
For the full schedule of checks, cleaning and replacement, see our sump pump maintenance guide.
How do you check if a sump pump is working?
For most home sump pumps, adding water to the pit is the most reliable test. Before you start, make sure the floor and the outlet are dry and the pump is plugged in. Take the cover off the pit if it has one.
- Fill a large bucket with water.
- Pour the water slowly into the pit, away from the pump and its cord, until the float rises.
- Watch the pump start on its own and lower the water.
- Watch it stop once the float drops back down.
- Go outside and check that water came out of the discharge pipe and is draining away from your house.
Keep your hands out of the pit the whole time. If the pump starts, empties the pit in a short time and shuts off without fuss, it passed. Write down the date and anything unusual you noticed, such as a new noise or a slower start, so you have something to compare against next time.
Can you test a sump pump without water?
Sometimes. On a pedestal pump, the motor sits on a stand above the pit, and some models have a float rod you can test from above. But float designs vary, and running some pumps dry can damage them.
Check your manual first. Never reach into the water or force the float, and if in doubt, use the bucket test.
On a submersible pump, the float sits down in the pit, often under water. Reaching in puts your hand in water next to a powered pump, so use the bucket test instead. It also tells you more, because it shows the pump actually moves water out of the house.
What each test result means
How the pump behaves during the test points to what is wrong. This table matches what you see to the likely cause and the safe step you can take yourself. Every step here is a check, not a repair.
| What you see | What it usually means | Safe step |
|---|---|---|
| Starts, empties the pit, stops cleanly | The pump is working | Note the date and test again next year or after the next big storm. |
| Nothing happens | No power, a tripped breaker, a stuck float, or a failed switch or motor | From a dry spot, check the plug and the breaker. Look for a float caught on the pit wall or cord without reaching in. |
| Hums but does not pump | Possibly a jammed or worn impeller (the spinning part that pushes water), a motor problem or an electrical fault | Unplug from a dry spot and call a plumber. A humming pump can burn out. |
| Runs, but the water barely drops | A blocked intake, a blocked or frozen discharge pipe, or a worn or undersized pump | Check the outdoor end of the pipe for ice, snow or debris. |
| Runs and will not stop | A float stuck in the up position or a faulty switch | If the pit is empty and it keeps running, call a plumber. Running dry wears a pump out fast. |
| Water rushes back into the pit after it stops | A faulty, missing or poorly installed check valve (the one-way valve on the pipe above the pump) | Call a plumber. The pump will keep cycling and wear out sooner. |
| Grinding, rattling or heavy vibration | Worn parts or debris in the pump | Call a plumber before the next storm. |
What about the outlet and breaker?
If the pump did nothing, rule out power first. You can do this without touching the pump. Stand on a dry floor and check the plug is fully in.
If the outlet has a reset button and the area is completely dry, try resetting it once. Then check your panel for a tripped breaker and reset it once.
If the breaker or the outlet trips again, stop. It means something is drawing too much power or there is moisture where there should not be, and resetting it again will not fix that. Call a plumber for the pump, or a licensed electrician for the outlet or wiring.
If there is water near the outlet or the cord, do not touch anything. Shut the power off only from a dry spot, and if you cannot do that safely, stay away.
How do you test a battery backup pump?
A battery backup is a second pump that runs from a battery when the main pump fails or the power goes out. Test it two to five times a year, following its manual, since the right test depends on the model. If you are not sure how yours works, a plumber can show you.
While you are there, check that the battery charger shows it is charging and that the alarm, if your system has one, sounds when it should. If you are still deciding whether a backup is worth it, we cover that in Do You Need a Sump Pump Battery Backup?
When a test means it is time for a new pump
A failed test on an older pump often means replacing it makes more sense than repairing it. Sump pumps generally last about 10 years, per Government of Canada guidance, though you should also check your manufacturer's advice.
A pump that runs often or sits in a silty pit can wear out sooner. If yours is near that age and hums, struggles or makes new noises, plan to replace it before it fails in a storm.
If your pump failed the test, is getting older, or you would rather have a plumber check it, book a sump pump service visit. We test the pump, float, check valve and discharge line, and explain the work and the price before we start.
If water is already rising, call our 24/7 emergency plumbing team: Burlington 905-332-8222, Oakville 905-842-6222, Hamilton 905-545-4222.
