I am unfamiliar with the E02 error. I haven't experienced any errors yet with my setup. I can only speak to my experience with my rebel 50aH and the SOK 100aH. They have both been trouble free for the period I have had them. (1 year rebel, 4 months SOK).I'm slowly reducing the Boost voltage on the HQST controller to see if there is a way to eliminate the E02 error on my Weize LFP that way. Do you have any thoughts on your batteries? If you could, what battery would you go with? I wonder if I'll find out that I just can charge the Weize as hard as other batteries. I got the Weize for its BMS, though, which was supposed to handle low temperatures well.
I see from the manual that the E02 error is defined as:
"Battery voltage has exceeded controller limit.
Check battery bank voltage for compatibility
with controller"
That seems strange. What battery have you connected to?