Originally Posted by Delta-T
You can not assume that new batteries are good. And your charger could be faulty and overcharging. Or as mentioned before, you have something constantly drain that battery. You said you have two 12v batts in series? 24V system?
The house bank is 2x Group 27 in PARALLEL.
There are actually 2 banks. The starting ban is a single Group 27. Then theres the house bank. Everything is a 12v.
Could it be the uneven size of the banks?