Don’t panic! Often times what seems like a really big problem is likely an easy fix. The first key in fixing any issue is determining the problem.
Step 1: Check the Power Supply
If the light on your power supply is not on (If the light on your power supply, is on, please proceed to Step 2.)

Plug something else into the outlet to see if the outlet has power. If the outlet has power, unplug the controller from the power supply so the power supply is not connected to anything except the outlet and see if the light on the power supply comes on. If the light on the power supply still does not come on your power supply is defective.
Step 2: Check the Controller
If the lights on your controller are off
Unplug the pump body from the controller. Do the lights on the controller turn on now? If the controller runs without the pump plugged in, but fails when the pump is plugged in, your pump body is defective.
If the lights on your controller are on
Does the controller not respond to any inputs? If so, it may be locked. To unlock, press the “+” or “-” button for three seconds until the LED indicator lights flash twice.
Does the controller display an error code?
- Older Model Pumps, similar to the controller shown below, display an error code based on which LEDs lights are blinking / flashing as shown in the chart below.

Error Code | Issue | Solution |
![]() | Incorrect Voltage | Replace the AC/DC power supply |
![]() | Controller Overheating | Make sure the controller is not installed in a high temperature area, like near a chiller, and is not exposed to direct sunlight. |
![]() | Impeller Stuck / Won’t Spin | (1) Open up the pump and check to see if something is caught inside the pump body. (2) Inspect the impeller for any signs of damage or warping. (3) Check bushing are installed properly (4) Check that the power supply, controller and pump body are correctly connected. (5) Clean Pump in VInegar Bath. |
![]() | Pump Running Dry | (1) Make sure pump is completely submerged in water. (2) Make sure pump input isn’t blocked. (3) Clean Pump in VInegar Bath. |
![]() | Abnormal Current | (1) Check for any damage to the power supply and its cable. (2) Check controller and controller cable for any signs of damage. Replace defective component(s). |
- Newer Model Pumps, similar to the controller shown below, display a digital error code beginning with the letter E followed by a number as shown in the chart below.

Error Code | Issue | Solution |
E1 | High Voltage | Replace the AC/DC power supply |
E2 | Low Voltage | Replace the AC/DC power supply |
E3 | High Current | Replace the AC/DC power supply |
E4 | Pump Running Dry | (1) Make sure pump is completely submerged in water. (2) Make sure pump input isn’t blocked. (3) Clean Pump in VInegar Bath. |
E5 | Impeller Stuck / Won’t Spin | (1) Open up the pump and check to see if something is caught inside the pump body. (2) Inspect the impeller for any signs of damage or warping. (3) Check bushing are installed properly (4) Check that the power supply, controller and pump body are correctly connected. (5) Clean Pump in VInegar Bath. |
E6 | Controller Overheating | Make sure the controller is not installed in a high temperature area, like near a chiller, and is not exposed to direct sunlight. |
If your controller is powering up and is not displaying any error code and you are able to turn the pump speed up and down and use the Pause button, than the controller is likely working correctly.
Step 3 – Check the Impeller
Simplicity 120DC and 240DC Skimmers Only
Remove the impeller and check for any signs of damage or wear to the magnet. If there are obvious signs of damage the impeller needs to be replaced.
If the impeller looks good, place it back into the pump body and check to make sure that it will spin freely within the pump body. The white ceramic shaft of the impeller must be able to spin freely on the bushings inside the pump body, however without regular cleaning these parts can easily get stuck together from the buildup of calcium and other deposits. If your pump requires a flick of the impeller to start it is time to clean your pump in a vinegar bath.

Simplicity 320DC, 540DC and 800DC Skimmers Only
If the impeller looks good, check that the plastic ring attached to the impeller is able to spin freely on the ceramic impeller shaft. This plastic ring has a bushing inside and it is common for calcium and other deposits to build-up in this area which can prevent the impeller from spinning freely. If this plastic ring is not spinning easily a cleaning and vinegar bath is required.
Unsure how it should operate? Please watch the following video and skip ahead to 0:55 for a demonstration of how easily the plastic ring should spin.
Step 4: Clean Your Pump
In order to keep your pump running, it is important to soak your pump in a vinegar baths every month or two to remove calcium and other deposits from the impeller shaft, bushings, motor block and other components which will allow your impeller to spin resistance free.
For the best results, please completely disassemble your pump and soak it in a 50/50 mix of vinegar to water for at least 24 hours. Use a small toothbrush or other instrument to carefully clean all components. If white ceramic shaft of the impeller still does not spin freely on the bushings after cleaning, then you will need to replace the impeller and bushings. Prior to reinstalling, please rinse all parts in water to remove any residual vinegar.
If both your power supply and your controller appear to be working correctly and your impeller is in good condition and can spin freely within the pump body, then you likely will need to replace the pump body / motor block.
In case you missed it above, the following video offers a complete step by step guide on how to check and clean your pump:
Need to purchase parts? Still need more help figuring out what is wrong? Please contact us we will be happy to help you out.
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