When your pond pump stops working, your fish and biological filter are
at risk. Depending on many factors, you may have as little as a few
hours to avoid a catastrophe. Hopefully you have planned ahead and you
have a spare pump ready to go anytime the need arises.
With the following information we hope to be able to help you
troubleshoot and get your pump back to pumping water thus saving you
effort, frustration, and possibly the expense of a new pump.
These steps are specific to submersible pond pumps. For external pumps,
refer to the manufacturer’s literature. You can find the Sequence Pump
manual for the 4000 series
here (1MB PDF file will open in a new tab or browser window).
The first step is to observe the pump to see exactly what is happening.
Has the pump completely stopped, or is there a hum, or maybe a loud
If there is a loud sound coming from the pump the issues could be:
A. Vibration against a hard surface like a skimmer.
Placing something like a foam mat under the pump may be enough to solve this.
B. There may be debris around the pump impeller or the impeller itself may be broken.
Inspect the intake area thoroughly.
C. A loud grinding sound may indicate the bearings have failed.
The pump will need to be replaced.
If there is a hum still coming from the pump but no flow the issue could be:
A. A clog in the intake or in the discharge pipe.
the pump intake to ensure that it is free from debris. If clean and the
problem persists, try placing the pump in a tub of water with no pipe
attached and see if it works. If so, you will need to clean your
B. Vapor lock (air in the pump). Vapor locks can be common when reinstalling a pump after cleaning it.
the pump on its side and back and forth while submerged. You may see
bubbles rise from the pump. If possible, do this with the pump on.
C. The capacitor may have failed.
A new pump is needed.
If the pump does absolutely nothing the issue could be:
A. Engagement of the thermal overload protection.
submersible pumps feature a thermal overload protection to minimize
damage to the pump should it overheat. There are multiple reasons that a
pump could over heat (such as clogs or too much resistance), but the
most common is lack of complete submersion, especially if the pump is in
a skimmer. If a skimmer net/basket/pad gets clogged the water level in
the pump chamber can drop. When this happens the pump will shut off.
When it cools off it can restart. (Note that when the pump shuts off
the skimmer will fill back up, so the fact that the skimmer is full when
the pump is off does not indicate that this was not the problem).
Give the pump time to cool down, this may take up to an hour. Then try
again, ensuring that the pump stays submerged. Repeated engagement of
the thermal overload protection can damage the pump. Keep your skimmer
clean and you may want to invest in a Pump Protector.
B. Problem with the GFCI.
See if your GFCI has tripped. If
so, reset it and try again. If it trips again you either have a bad
pump, faulty GFCI, or some other device using the same GFCI is the
problem. Test the pump on another GFCI.
C. No electricity to pump.
Check the outlet with another electrical device and/or check the pump on another outlet that uses a different circuit.
Proper care of your pump is the key to a long pump life. Inspect your
pump intake regularly for restrictions. Anytime you see the flow
reduced, check the pump ASAP. If you are unsure how to thoroughly clean
your pump, refer to the instructions that came with it or contact AquaNooga.
Never pull or carry the pump by the cord. And, of course, start with a good-quality pump that is well-suited for your application.