I bought one of the small Noco 12 volt battery tenders awhile back when I was not able to drive. Did not end up using it as it always seemed someone else was using my car... Wanted to hook it up today to my Subaru Outback and saw that there are various settings based on if the batt is just an old school 12v, AGM, extra flooded, etal. The factory OEM battery just has CCA on it and a part number. Extensive Googling got me nowhere except that some claim it is flooded. Some say regular and some say AGM. Subaru parts lists I found are no help. I could call the dealer, but I think that is about a 50/50 chance of a correct answer. So, if I hook it up as just a regular 12V will the world end? kris
The lack of such basic info on the battery seems common. It is likely a maintenance free flooded. Charging an AGM with flooded settings could lead a shorter life for the AGM. Sealed batteries like AGM, gel, and maintenance free don't have a way of replacing water from off gassing. Their charge profiles are intended to reduce that off gassing. The maintenance or float charge difference between the types likely won't be an issue. The amperage draw for a full battery will be low. I suspect any potential harm is less than letting the battery sit for extended periods without a maintainer. Not going to apply to your maintainer, but my Outback manual says not to charge the 12V at over 10amps.
My (very limited) understanding, basically from reading in between the lines in my CTEK 4.3 manual, is that the only difference is for certain* AGM's only, the "snowflake" setting is recommended. It's for extreme cold weather, uses slightly higher charging voltage. FWIW, I installed a Optima Yellow Top battery, in September of 2015. With our usage so sporadic, I've had it on the charger more than off, and IIRC for the first few years I didn't use the snowflake setting. It's still going strong. * Pretty sure I saw the expression "spiral-wound" somewhere, like the 6-pack style Optimas, but not finding it at the moment
