I cannot find a set rule. My AGMs are a lot different than say Lifeline. Seems to be a lot of variability. Deka wants you to contact them for special instructions if you try to charge at over 95 degrees.
I cannot say what anyone else's AGMs would do. But in my testing I found either temp or any kind of aggressive charging as they approach full charge can start accelerated outgassing. The two together (even just 90 degrees out and something a few tenths over temperature compensated float) really have a hair trigger.
Mine probably outgas more easily due to not being broken in yet, leading a life of rare 20% discharges and days on end on float or just below float voltage (I sometimes set them up for float at heat of the day which means a few tenths below over night).
I should test for outgassing again now that they have burned in at float voltage.
It is about time to hard wire some resistors into one setting on the solar controller and see how the LandStar does maintaining them. I am a little resistant to it running up the voltage every day in the heat, but I should test it out, since only a few hours a month should not hurt much, and will keep hard sulphation at bay.
Jim
