I'm hoping that someone on this forum can help me with a recurring/repeatable issue that I have been having with the Flexboss 21. I've called Signature Solar number times and they don't believe the unit is functioning out of spec. As this is a the second Flexboss 21 that I've had, I'd be extremely worried if both had this same rare issue. Here is a brief synopsis of the issue, and while I'm happy to share more information, I don't know how to put it into the best technical terms, so I will just explain what I'm seeing.
First I have a Flexboss 21 (FAAB-2525) that is installed in my garage along with two EG4 Indoor batteries, and PV strings (42, 410w panels) that come off the attic directly into my inverter (no combiner, disconnect, or breakers). I then have a 60 amp breaker that backfeeds into the main breaker box. So it supplies any excess solar to the main breaker to feed loads or back to my utility for buyback.
My issue is that if I have a high load (I don't know how long it has to be, but over 30 minutes based on the logs) the PV strings will stop growing in power. So if I am pulling in 4kw @ 8am off the panels, and the load stays over a certain threshold for longer than a certain amount of time, the PV will stop growing. Today I had this happen in which my AC is running nonstop (because it's going to be 111*) and my mini-split in the casita is doing the same, and pool pump etc are all running. Due to this the PV stopped growing at 3kw. I didn't notice it, so the batteries never charged today and it kept pulling from the Grid instead of resetting the PV strings. When I notice this happens my only solution (that I know of) is to restart the inverter entirely and it will then jump from 3kw to (in the case of today) 13kw immediately. I have provided the logs from today, and a screenshot from today, when this happened. I also had this happen while I was on vacation 6/1/26 and pulled the logs and snapshot of the same (you should see the spike in Solar PV from a low number to one much higher, the only change is a restart of the inverter.
Can someone help me diagnose why this is happening, and how it can be fixed? I know I am not on the latest firmware, but when I seen the release notes, I didn't see anything in regards to this issue. It won't let me upload the excel from EG4 website, but if anyone needs it I can send.
