Unfortunately I can't help with an spare but...
Before you order a new one...it may be better to ship it to ecotech and let them look at the dryside. I thought my controller went bad and it was actually a bad dry side causing the controller to throw a code indicating it was malfunctioning. The shaft was slightly bent...the completely rebuilt the dry side and sent it back. Total cost?
...they charged me $13 to cover return shipping. The unit was more than 2 years old, and not covered under any warranty.
