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What's wrong with my sump pump?

If you have a sump pump installed in your basement, you want to be confident that it will work as expected when needed. Sump pumps are designed to reliably remove water from your basement or crawlspace and pump it away from your home to a location where it's no longer a concern. When a big storm is headed your way, the last thing that you want to worry about is if your basement will be ruined by flooding – especially after you've taken the time and effort to protect yourself.

Unfortunately, sump pump problems can occur – both minor and serious – that prevent it from doing its job correctly. Sometimes it's a problem with the pump itself; in other situations, a pipe could be blocked, or the sump pump might not be getting the power it needs. During a very heavy storm, your pump might simply not be strong enough to move all of the water out as quickly as needed. And the lifespan of a sump pump depends a great deal on how hard it works, so if yours has been pushed to the limit, or if you've noticed the pump isn't working as well as it did before, it might be time for a new model.

Whether your sump pump keeps running for a long time or isn't turning on at all, our sump pump troubleshooting guide is designed to help you identify the most likely causes of pump problems and how to fix them.

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Troubleshooting

Why won't my pump start or run?

Float switch is not being raised high enough
Check to see if float ball is stuck on something. if so, remove obstacle. If need be, reposition pump or remount switch in new position so it cannot get stuck.

Water level might not be high enough to engage switch. Raise float manually or add water until float is at activation height to test switch.

Pump is not receiving enough electricity
Check outlet to ensure it has power. If not, replace fuse or reset breaker in home's fuse/breaker box.

Plug pump directly into an outlet without using an extension cord.

If extension cord MUST be used, ensure that it is of a heavy enough gauge wire to support the length of cord and horsepower of pump you're using.

Check that wire providing power to the outlet where pump is plugged in is adequate.

Pump should be plugged into an outlet that is fed by its own circuit breaker (or fuse). If circuit breaker feeds power to other outlets or appliances, have outlet installed that is fed by its own breaker.

Why does my motor hum but little or no water moves?

Motor is just humming -- not running
Follow diagnostics above for "Pump won't start or run"

Pump is air-locked
Drill 1/16" to 1/8" anti-airlock hole in pipe just above pump's discharge and just below check valve.

Check valve is stuck closed or installed incorrectly
Check valve usually has an arrow on it indicating water flow. Ensure it is pointing up toward discharge, not at pump.

Inspect to see if check valve is stuck closed.

Impeller is damaged
Inspect impeller for worn or missing blades. Replace impeller if needed.

Why does my pump eject water for a bit but shuts off early?

Pump is overheated and shut off by thermal overload
Be sure plump is plugged directly into outlet. If extension cord MUST be used, ensure it is heavy enough gauge for horsepower of pump and length of cord. It is recommended that the outlet be fed by its own circuit breaker (or fuse). If the breaker (or fuse) sends power to other things, the pump can be shorted of voltage when it starts.

Float switch is out of adjustment
Check if pump shuts off before float ball is all the way down. If it's shutting down too early, adjust float switch per instructions in owners' manual.

Float switch is bad
If adjustment above did not resolve problem, or no adjustment is possible, replace float switch.

Why does my pump run continuously?

Pump cord and float switch cord are plugged in separately.
Plug pump cord into piggyback connector on back/side of float switch plug. Put the combination into a single receptacle of an outlet.

Float switch is stuck
Inspect pit for anything that can cause the float ball to get stuck and not settle to its 'off' position. Remove obstacle or relocate pump or switch to avoid the obstacle.

Float switch is out of adjustment
For tethered style floats, ensure there is a minimum of 3" of cord between float ball and cord mounting bracket.

For vertical style floats, check adjustment of rubber stopper under the float ball at the bottom of the float rod.

Water is not being discharged from pit
See item above labeled "Motor hums but little or no water is ejected from pit"

Simply have too much water coming in
Check discharge to be sure water is being ejected from pit. If it is, but water level in pit does not drop, then you simply have more water coming into the pit than the pump can move out. If pit is not overflowing, no real issue is present but you may wish to have a spare pump on hand in case the pump fails from over-use.

Using vertical style or electronic probe style float switch in sump pit that gets laundry water
Laundry water builds up soap scum on the float switch which will impede float movement.

Soap scum on probes of electronic float switch can make contact even when water is gone "fooling" the switch.

Only an effluent style pump with tethered style switch should be used if laundry water is to be pumped.

Why does my pump start and stop too often?

Using a pump with vertical float where a pump with tethered float might be better
If your sump it is large enough in diameter and deep enough, using a pump with a tethered style float switch will allow the pump to be off longer between pump cycles.

Sump pit is very small
A very small sump pit will simply not hold as much water. Enlarging the sump pit (if possible) would be wise.

Float switch is out of adjustment
For tethered style floats, ensure there is a minimum of 3" of cord between float ball and cord mounting bracket.

For vertical style floats, check adjustment of rubber stopper under the float ball at the bottom of the float rod.

Water is coming back into pit from discharge pipe
After pump has run, inspect to see if water is coming back into pit through the sump pump. If so, check valve has failed. Replace check valve.

Simply have too much water coming in
Check discharge to be sure water is being ejected from pit. If it is, but water level in pit does not drop, then you simply have more water coming into the pit than the pump can move out. If pit is not overflowing, no real issue is present but you may wish to have a spare pump on hand in case the pump fails from over-use.

 

Why is my pump noisy?

Discharge pipe is rattling or banging against wall and/or floor joists
Put insulating foam between pipe and wall and/or joists.

Can also try hanging the pipe with an exhaust hanger from an auto parts store.

Install a section of flexible rubber hose (like radiator hose) between the pump discharge and the discharge pipe to provide vibration insulation.

Check valve slams shut causing a bang just after pump shuts off
Install a section of flexible rubber hose (like radiator hose) between the pump discharge and the discharge pipe to provide noise insulation.

You may be using a pump that is higher in horsepower than you need. It is causing the water to move too fast in the pipe. After the pump shuts off the water column keeps moving upward for a moment, then slams down

Pump is sucking air at end of its cycle
Adjust float switch per the owner's manual so it shuts off before it starts sucking air.

Pump itself is vibrating
Inspect impeller for broken or missing blades. Replace impeller or pump to rectify but also inspect sump pit to eliminate debris that could damage new item.

Why does my fuse or circuit breaker blow when my pump tries to run?

Water got into cord and/or float switch connector (especially possible if your breaker is a GFCI type breaker)
Separate pump plug from switch plug use hair dryer to dry them out.

Remove cord connector from top of pump and dry out with cloth or hair dryer.

Impeller is stuck or jammed with debris
Remove screen from bottom of pump and make sure nothing is preventing the impeller from moving freely. Remove any obstructions.

Using an extension cord or wiring to outlet is too light
Check to make sure the wire supplying power to the pump is appropriate for the horsepower and amp draw of the pump that's in place.

Float switch is bad
Plug pump directly into outlet (without plugging into float's piggyback plug) to see if pump runs without popping breaker or fuse. If it does, but it pops fuse/breaker when plugged in through float switch, the float switch is bad. Replace the float switch.

Pump motor has a shorted winding
Replace the pump.

What is the most common cause of sump pump failure?

Probably the most common cause of sump pump failure is electrical in nature. Plugging the pump into an extension cord, or an outlet that shares a circuit breaker with other electrical items, can cause the pump to receive low voltage. In order to run it then has to draw higher amps. That causes the pump to run hotter. Heat is the enemy of electric motors and can shorten the life of a pump dramatically. We recommend the pump be plugged directly into an outlet (no extension cords) and that the outlet be the only thing powered by the circuit breaker (or fuse) that feeds it.

How do I check my sump pump to see if it's working?

If your pump is equipped with a piggyback-style plug (where the pump plugs into the back or side of the switch plug) then you can unplug the pump's plug and put it directly into the power outlet. The pump should immediately run. It will continue to run as long as you leave it plugged in this way. Do not leave it plugged in for more than a few minutes so that the pump does not overheat.

To test to make sure the float switch is also working, or if your sump pump has a switch that plugs directly into the body of the pump, you will need to lift the float switch to its 'on' position. This will vary depending upon pump model so consult your owners' manual for that information. To avoid possible electric shock, use a broom handle or similar non-conducting item to lift the float switch. The pump will run when the switch reaches its 'on' level.

Where can I get repair parts for my pump, or accessories I might need?

Parts listed in the manual can be ordered directly through the store where you bought your pump; or can be ordered directly through us. In most cases, the store is able to special-order the parts (they won't stock them) and sell you the parts for less than you would pay by ordering through the factory. Also, they usually do not charge shipping charges (we do). It is best to talk to someone at the store's "Special Orders" desk. Have our toll-free number and the part numbers you need with you. If the person at the store does not know how to order parts, please have them call us while you are there.

If ordering directly from us, you would normally receive your order in 7-10 business days. Expedited processing and shipping is available at additional cost. We accept Mastercard, Visa, and American Express (not Discover).

I think I have a warranty issue with my pump. How do I proceed?

We generally proceed with warranty through the point-of-purchase. Any authorized retailer of our pumps can handle warranty replacement. The other way to process warranty is directly through us. If you wish to pursue this method, call us first. Keep in mind that a warranty states the item will be "free from defects in material and workmanship". Warranty does NOT cover normal wear, damage caused after the item leaves the factory, rust or corrosion, etc.

Still have questions or need help?