[LionStar]

We have been at an RV park for the last three weeks, hooked up to shore power. Got a fault and temperature alarm on the inverter panel today. Opened the house battery bay and one battery is hot and bubbling. The other five batteries are cool to the touch. How can I disconnect the house batteries to let this cool down enough to check/add distilled water?
Are the house batteries necessary if using shore power?
Just got the coach out of repair for major electrical issues before coming to this park...
I know this may have been addressed in other threads, but I have not found it yet and don't want to take too much time. Any help would be appreciated.