Sump Pump Running Constantly
A sump pump that runs nonstop or cycles every few minutes usually has a stuck float switch, a failed check valve letting water flow back into the pit, or more groundwater than it can handle. Check the float and check valve first. A new check valve or float switch typically costs $100 to $350 installed; a new pump costs $400 to $1,200.
Typical pro cost
$100 to $1,200
- Urgency
- Fix this week
- DIY difficulty
- Medium
- Time to fix
- 30 minutes to 3 hours
- Prices
- US typical range
Last reviewed October 2026
Signs it's this problem
- The pump runs even when the pit is nearly empty
- It turns on every few minutes in dry weather
- You hear water rush back into the pit after it stops
- The motor is hot or the pump hums constantly
- Higher electric bills
Common causes
Stuck float switch
The float catches on the pit wall or cord and stays up, so the pump never shuts off.
Failed check valve
Water in the discharge pipe falls back into the pit and restarts the pump.
High water table
After heavy rain or snowmelt, groundwater can keep the pit filling for days.
Undersized or worn pump
A weak pump cannot keep up and runs much longer than it should.
Discharge water returning
A discharge outlet too close to the house lets the same water soak back to the foundation.
How to fix it, step by step
- 1
Watch one full cycle. Note whether the pit actually empties and how fast it refills.
- 2
Unplug the pump and check the float moves freely. Move the pump or cord so the float cannot catch.
- 3
Listen when the pump stops. A rush of water back into the pit means the check valve has failed.
- 4
Make sure the outside discharge pipe is clear and empties at least 10 feet from the house.
- 5
If the pit refills fast in wet weather, the pump may simply be working hard. Add a battery backup for storms.
- 6
Replace the check valve, float switch or pump if they are worn. Pumps usually last about 7 to 10 years.
Tools and materials
- Flashlight
- Stick or broom handle
- Screwdriver
- Replacement check valve (if needed)
Approximate DIY cost: $20 to $60 for a check valve
Call a pro when
- The motor is hot or smells burnt
- The pit floods even with the pump running
- The pump is more than 7 to 10 years old
Sump Pump Running Constantly cost
| Job | Typical cost |
|---|---|
| Check valve replacement | $100–$250 |
| Float switch replacement | $150–$350 |
| Replace a sump pump | $400–$1,200 |
| Add a battery backup pump | $400–$1,000 |
Ranges are typical US prices compiled by FixHomeCost. Prices vary by region, home and contractor, so compare 2–3 local quotes.
Common questions
Is it normal for a sump pump to run every few minutes?
After heavy rain or snowmelt, yes. In dry weather, frequent cycling points to a stuck float or a failed check valve.
Can a sump pump run too much?
Yes. Constant running wears out the motor early. Find the cause or add a second pump if groundwater is very high.
How do I know if my check valve is bad?
If you hear water rush back into the pit when the pump shuts off, or the pit refills right away, the check valve is likely failing.
How long do sump pumps last?
Usually about 7 to 10 years. Pumps that run constantly fail sooner.
Related guides
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