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If you allow your battery to get to 14.2/14.4 volts on the bulk charge, it will boil them enough to keep them mixed up. My controller (C-40) holds this voltage an hour (Bulk) and then drops down to 13.6/13.8 volts (Float) and hold there for the rest of the day. (On a typical “good” day) Some days doesn’t have enough sun to get them up to the bulk voltage level and hold them there for an hour but the voltage always seems to creep above the 13.4/13.6 volt level and they still boil a little.. (Bubble now and then)

If you allow the voltage to go much above 14.4 volts, they boil too much and dry out much faster. Boiling too much also makes a mess on the tops of the batteries! It’s not necessary to boil the crap out of them..

The settings that I suggest works well for me and has for years. Just so it’s understood, I have my battery in a climate controlled environment, in my living area, with me! I know if they are too cold or too hot. Temperature does make a difference in the settings. A warm battery boils easier than a cold battery. If you have your battery in a shed outdoors or in a cold basement, my suggestions are wrong. Just an FYI..

Wretha, this may apply to your inverter issue..

I was working with a fella that had the same issue. During a charge period, his inverter would shut down for an hour or so and then normalize. (Battery mounted in a non-heated area) I walked him through the bulk/float settings several times, keeping the bulk setting below the max. input voltage limit of his inverter, to no avail. He would check the voltage at the battery during float time and sure enough, the voltage was going above the physical/adjustable setting in the controller! (Too high for the inverter to accept) One thing that he didn’t tell me.. He was using the temperature compensation thermistors at the battery! This bypasses the adjustable setting in the controller and allows the bulk to go to the maximum setting to a cold battery! Needless to say, we unplugged the thermistors and all is well BUT the battery will not achieve a complete, full charge, being they are cold and a cold battery needs a higher voltage to charge completely. The controller was just doing what it was designed to do..

When your inverter is failing, check the battery voltage at the inverter and see if its higher than the maximum input voltage limit of the inverter.. (Or very near)