AGM and Flooded in same system?

[skamiv]

This is my first post to this forum, and English is not my native language, so bear with me

We currently have a temporary system with some 12V flooded battery's and cheap PWM solar-controller loading
them from 100W solar-panel at our summer cottage. Those battery's are about 3 yrs old, so they have plenty of life left.

We are now updating our system (24V system, more batteries, panels, MPPT controller and inverter)
and we already purchased inverter and got 2 AGM battery's(12V) in the same deal. So now we have 3 flooded batterys and 2 AGMs.


Can we hook those AGMs to our current setup and make one big 24V system and load it with some MPPT:




Or should we make 2 separate 24V systems with some switch to change from:


Or should we make 2 separate systems, one with 24V and another for our 12V appliances:

[Sunking]

Nope you cannot mix AGM and FLA because they have different voltage settings. If you set for AGM, lower voltage of 14.4 volts, the FLA will be undercharged and destroy it. If you set the voltage for FLA of 14.8 volts will overcharge the AGM and destroy it. Or split the difference of say 14.6 and risk destroying both of them. Take your pick.

FWIW if your FLA batteries are 3 years old are due for replacement. Not going to matter much because all your batteries are in parallel which means very short battery life.