All the problems Rexair had with those first circuit boards forced them to change the board's design as the board had an 8 year warranty. If you look at the board in your machine compared to the replacement board, they are very much different. Interestingly, the new boards are shipped complete with the new board holder, which will not work with your machine. The service man has to very carefully take the board holder apart without destroying it, to put the new smaller board into the old holder. I've done it so many times now, it's a piece of cake. But it sure wasn't the first time I had to do it.
Most people don't baby their machines, which is why we saw the board failure early on. Today, most of the E2 gold models have had their boards replaced and even with hard use (as most people give them) they are not returning for a second circuit board. If they will let you, you might want to actually watch as they service your cleaner.