?Problem with AGM batteries in new Grady White boats

[drm1]

I have a new 2025 Freedom 285 with 65 hours on the engines. I got a sudden 11V battery warning on my Garmin chartplotter. After 28 hours of shore power the batteries are not charging (I have a ProSportHD20 battery charger). I don’t know if it’s a charging problem (the ProSport is correctly recognizing the AGM batteries however) or bad batteries. The dealer plans to replace the AGMs with flooded batteries. Good idea?
Also anyone else have a similar experience?
I had a previous Freedom 275 new build in 2022 with no similar issues.

 

[seasick]

You should load test the batteries first to se if any are shot.

There are lots of possible reasons for your low voltage warning but you didn't provide enough info to diagnose.
For example, How many batteries in total, how many charging ports? ( The Pro Sport 20 is a 2 bank charger and if you have more than 2 batteries, may not be the best option to maintain charge on all batteries) What lights on the charger are lit and are they blinking?

If you get the warning when you start a motor, that is a common occurrence and is probably a weak battery (house). If you have added accessories since purchase and the warning recently started after adding loads ( like a amplifier/stereo head end) you factory wiring may be under-sized for the load.
What were you doing and what were the motors doing when you got that alarm? ( Motors off, cruising, starting one or both motors)

Lots of possible causes.