We have a zanussi zsf6606 dishwasher and recently it has stopped heating up. If it's turned off at the mains for a while it works but it hasn't heated up today at all. How easy is this likey to be to repair. Main issue being we rent, ll will not repair or replace it as 'he doesn't supply dishwashers ' despite it being in when we moved . Also he has paid out a lot for various other things that have failed through wear and tear recently so I don't want this to be the straw that gets us a section 21.