E4 error occurred after the plumber changed the pipes.

Hi,

I have a dishwasher Whomson thominox silence.
It was working fine until a few weeks ago, but now I get an E4 immediately when it starts.
The issue started just after a plumber came to change the piping in the room.

– Can it be related ?

I disassembled the machine, looking for anything unusual in it, and tested a few things, but everything seems fine.
The E4 error did not appear immediately when I restarted it. Instead, it did nothing for at least 30 seconds. During its working state, it was immediately filled with water. After the 30 seconds, there was some water sound. It’s likely a coincidence, but the water started to get in exactly when someone used the sink. The dishwasher and sink are next to each other and their pipes are connected.

– Is it a pure coincidence or could the water intake from the faucet have triggered the start of the dishwasher ?

The E4 error reappeared after 30 seconds of filling with water. My guess is that I obviously removed some water from some components of the machine while trying to fix it. During the refilling of those elements by the machine, there was no error. But once it was done, it failed again.

Thanks for your help and sorry for my english. I hope my explanation is understandable though.