diplomat adp 8352?

cleaned filters but removed the centre toP nodule inadvertently.replaced items except i could not replace that nodule.like an idiot switched on and water cascaded out of the machine.removed black cover.swithched off and mopped up.poly'e piece dropped to base floor.switched on and it worked and then i saw water coming down the from somewhere? is it to do with this nodule? does it connect to anything?there is a thread on the base?
thanks