When the gas hose touches the dishwasher, an RCD trips

In the kitchen on the same outlet (no longer), but different extension cords, sit a refrigerator, microwave, washing machine, laptop. We bought and installed a dishwasher. (Naturally, if you turn it on, then take turns not to overload the network - because of this, they refused the electric kettle in favor of gas). There is a gas stove, gas pipe. An iron hose goes from pipe to plate. And if this hose touches the iron part of the dishwasher, the AZU will work. The indicator screwdriver on the dishwasher housing also lights up. There is no ground line in the apartment.

A friend said that the dishwasher is trying to ground itself in the pipe, or someone took the counters to it. Will buying dielectric couplings and rubber gas liner solve the problem or is everything really bad?