Why does my condensate pump keep running continuously?
A continuously running pump is usually caused by a stuck float switch or an air lock that keeps the motor running after water slows down. Smacking the float or unplugging the unit temporarily fixes it, but the switch can get stuck again after heavy rain or heavy use.
What the numbers show
Counted from the threads quoted below. How we count
- The most recent one is from October 2026.
- This comes up 16.7× more often in r/Plumbing than across the site as a whole.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
Found another way around this?
Share your steps and trade-offs so fellow engineers don't have to reinvent the wheel. No account required.
- 1Open up the unit and manually flip the float switchDid this help you?
- 2Lift the float off of the reservoir and move itDid this help you?
- 3Replace the pump by unhooking wires and linesDid this help you?
- 4smack the floatDid this help you?
- 5unplug it for a good 30 secondsDid this help you?
- 6cleaning it up to remove gunkDid this help you?
- 7checking if the float is too close to the wallsDid this help you?
- 8Using a vacuum to remove standing water in order to inspect and replace the pump.Did this help you?
- 9Checking where the discharge pipe comes out in the yard to ensure water isn't recirculating back into the systemDid this help you?
- 10Testing the water with dye, chlorine test kits, or meter checks to see if it is a leaking water main, city water, or spring waterDid this help you?
- 11Installing a backup sump pump, a battery backup system, or a water-powered sump pump for power outagesDid this help you?
- 12manually shut it offDid this help you?
- 13checking for an airlock or leak in the systemDid this help you?
In their words
Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.
“ever since May my sump pump has been running like this, with this much water always going into it. It doesn’t stop.”source ↗
“I’m the only house in the neighborhood having this issue.”source ↗
“Just cause the pump is running doesnt mean its working properly. Impeller could be toast. Discharge line may be plugged.”source ↗
“I plugged the pump straight into the outlet and the pump itself works, something is wrong with the float switch. But even when it ran it didn’t drain the sink.”source ↗
“now I can't seem to get the system up to full pressure.”source ↗
“The pump seems to prime fine and pressure builds fairly quickly up to about 42psi and then seems to stall there.”source ↗
“The pump is set for 30/50 psi, so if I don't manually shut it off, it doesn't turn off.”source ↗
“Any know why my sump pump keeps doing this? It gets like a air lock or something going on where the motor keeps running and i have to smack the floatnor unplug it for a good 30 seconds.”source ↗
“and randomly will do it after rains alot and the pump gets hammered for a bit but then when the water slows down it gets in a stuck state.”source ↗
“Yeah I've checked that out made sure nothing stupid with that i have the power cables running up off to the other side just to make sure the float wasn't getting suck and still no joy.”source ↗
Where this came up
People with this problem also raised
- 9HVAC condensate pump overflowing onto the floor
- 2How to test an old or unplugged sump pump
- 2Why does my AC compressor run continuously and never shut off?
- 5Why won't my well pump shut off when it reaches pressure?
- 6Why does my HVAC condensate pump sound like a jet engine?
- 2Why does my car cooling fan run constantly after starting?