1 - 3 hours
The battery was not holding a charge.
Initially, I was unable to get the screen started out of the bezel. the Iopener did not seem to get hot enough. After a couple of cycles in the microwave the Iopener burst open. Rather than give up, I tried a small electronics heat gun on the right top corner. The heat gun did the trick and I was able to slowly work the glass off the bezel. Once the glass was off the job was straight forward just as the instructional video showed. I completed the job in less than two hours.
The instructions for the Iopener should indicate heat times for 700 W or for larger full size microwaves. The instructions on the opener indicate not to reheat before at least two minutes had expired. I reheated after 5 mins and it burst.