Late last year we had a power surge that knocked out the controller on our pump. Got a guy to replace it ($800!) but in order to get the money back from the insurance he needed to write in his report that the damage was the result of the "supply variation". Now, short of standing there watching the controller during the power surge, you are just making the assumption that the damage was caused by the surge but all he wrote was that it was damaged.

So I need another plumber to come and look at it and write that it was damaged by the supply variation. I'm in Box Hill.

PM me if you can help. You can even come and see how not to work on a kombi gearbox, while you're there!