Dolphin Quantum - Refurbished

This product seemed to work well. It operated 1hr less than the instructions state it should. Be doing some research online, the operating times conflict with each other. So. I'm not sure what the correct time should be and whether I have a defect. Missed a few spots and didn't exactly clean the pool in a grid type process.

Purchased a refurbished unit that was supposed to be certified to be fully functional. It worked for a couple of hours and then stopped. Followed troubleshooting instructions but the unit is not working. Will be sending back.