How to Fix a Sewer Ejector Pump That Cannot Send the Water Up

Look to see if there is a float switch on the pump. Not all of them have this switch, so look for a floating ball connected to the pump by an electrical cord. If there are two cords attached to the basin, then the pump has a switch. The purpose of this switch is to trigger the pump when the water level reaches a specific height. The switch is annexed into the power cord of the pump, so the pump does not activate until the switch does. They are essentially connected one behind the other into the wall outlet.

Check to make sure the switch is working, starting with the circuit breaker. If everything is okay there, then next see if the wall outlet is working. If there is no interruption of electrical power, then disconnect the pump power plug from the switch cord plug and insert the pump power plug directly into the wall outlet. If it suddenly starts up, then the switch plug has gone bad. If there is still no response, then the pump is bad. In either case, both the switch and the pump are easy to replace.

Replace the pump. If the pump is the issue, then it can be replaced by taking out the faulty one and sticking a new pump inside. The new pump will also have a new switch attached to it. Plug them back together in the same piggyback configuration of one plug behind then other, and the system should be working fine again.

Replace the switch, if you've determined it is causing the problem. Flush out the dirty water that has collected in the pump by keeping it plugged in without the switch (as described in Step 2). Make sure not to let the water level get below the pump, or you could burn it out and will need to replace it, too. Remove the top of the basin, take the vent pipe from the top of it and disconnect the bracket that holds the waste line together. Use a towel to catch any water that spills from the vent pipe.

Lift the pump out of the basin, and make a pen mark where the electrical cord for the switch is attached to the pump. Connect the new switch at the same point where the previous switch was attached, so that the water level remains the same for activation. Check to make sure there is a sufficient enough air bleed hole at the bottom of the waste pipe. If there isn't one, drill a tiny hole, about 1/16 inch, near where the pipe enters the pump.

Reassemble the plumbing fixtures. Be sure that the floating ball is doing just that -- unhindered and not caught against anything.