Neff U1422 bottom element faulty - is it needed?

I have a Neff U1422N0GB/02 oven. After Aquacleanse function it was tripping the RCD when the main oven was switched on. Disconnected the bottom element and it works fine. Fan element tested OK. Is this bottom element needed other than for the Aquacleanse function, or can I just disconnect and isolate it? Is it safe to do this? Any tips on safely isolating it too?