I did contact them. Their site had no info, the support email address didn't work, so I resorted to the phone. They do NOT service CPAP machines. They either replace under warranty or they get tossed in the trash.
I did ask the customer service girl - E1 means you've got motor trouble, essentially your cpap has given up the ghost.
I hope this info can help someone else later. To be clear, I love the HC 234 and very well may buy another. I am not complaining about the machine, it's just a machine I have used for a long time that has reached the end of its service life.