If your Bosch dishwasher shows the E21 Error code on its control panel, this means that there are some issues with the pump and your appliance can’t drain the water after the cycle is finished. The appearance of this code is usually accompanied by the termination of the cycle.
What can cause the E21 Error?
If you see the E21 Error code, then your machine’s brain (main unit) does get a signal that the pump is not working how it has to. And there might be several causes for it.
The E21 Error may appear on the screen of your machine when the pump is blocked with dirt and grease, or when the impeller can not spin appropriately for the same reason. Another explanation for this error can be in the failure of the rotor of your device or the one-time system glitch, which is the easiest to fix.
How to fix the E21 Error?
As usual, the first thing to do when you see an error code is rebooting your appliance in order to exclude the system glitch from the list of possible reasons for the E21 Error. Turn your device off and disconnect it from the main power for 10-15 minutes. After the machine got some rest, switch it back on and check whether the code is still indicated on the panel. If it is, start inspecting the inner parts of your device.
To get to the pump you will have to detach the drain filter first, and the cause for the E21 Error can be in its blockage. So after you unplug your machine, open the door and take all the trays and baskets. Unscrew the drain filter and rinse it thoroughly. When you detach the filter, you can get access to the pump’s impeller.
Now you can inspect the impeller and its blades. It does happen very often that the impeller gets clogged with food and grease, so it is highly recommended to clean it at least once a month. Sometimes the blades can be broken and have to be changed to the new ones.
To check the pump itself you will have to take it out of the machine. As it is con-nected to the circulation module, you will have to turn your machine upside-down and remove the bottom panel. Disconnect all the wires, coming from the pump to the module, but don’t forget to take photos before doing it, it will help you in installing the pump back.
After all the wires are disconnected, turn the pump counter-clockwise and pull it out. To examine it, you will need a multimeter. Also, check the pump for all the visible signs of damage. In case it is out of order, it has to be replaced by the new one.
If the problem is with the rotor, then it’s is probably not greased enough, or just bro-ken. So if you have a special lubricant — try to grease the rotor with it and then install everything back and run a test cycle.
If you have difficulties with determining the cause of the error, contact a repairman, who will run a professional diagnostic and fix or replace the damaged parts of your device.