Polit Vaporetto 240 Trips the mains?

Hello
I have dismantled the unit & there is a small grey square unit attached to the steam reg valve the marking are as follows.
552/1EN2,4S70AIP
Serie 588
AC 230v 50Hz 13.5 va.

I am not sure what this unit is but if I disconnect it the steamer stays on & starts to heat the water, I need to know what this parts is & what it does.

There was quite a lot of scale in the boiler when I started the job but I have rinsed it out & all appears OK except for this problem.

Hoping you can assist.

Also where will I get parts for this unit.