Hey guys, this is my first post here. I searched the forums trying to find my answer, & it may/probably already exist but it eludes me.

I have a Trane BCU BMTW that keeps giving me a "F" fault code. I have an extra memory card that I will install, but I also wanted to upgrade the BCU image. I have done this many years ago, but I can't remember how i did that. Any advice would be much appreciated.

Thanks in advance