Help me figure out a problem with my house batteries
Posted: Fri Oct 07, 2022 11:48 am
I arrived at my boondocking spot on Tuesday afternoon. That evening the inverter would not power on. After a little investigation I found the house batteries were down to 11.2 volts. Of course the generator would not start either. Highly inconvenient! This was unexpected as I keep the coach connected to shore power when parked at home. I periodically check the voltage with a Victron battery monitor and it is always good. It checked out OK Tuesday morning before leaving home.
I ended up running idling the coach engine for about half an hour which put enough charge into the house batteries to start the generator. I ran the generator for an hour or so which brought the house battery voltage back up to 13+ volts. I didn't use any power over night except for a few minutes of LED lights. First thing in the morning the house batteries were down to 10.9 volts. Once the sun was up the solar started to slowly bring the voltage up but was still not enough to start the generator on Wednesday night.
Again, I ran the coach engine long enough to start the generator and then ran the generator all night so I could also run the furnace. I didn't have enough propane to do that for another night so I came home. Figuring that I have a failed battery I've removed them from the coach but they all test out good with a volt meter. These are gigantic 800AH Lifeline 6V batteries. All 4 measure 6.51v-6.45v. Today I will take them to my local battery shop and have them load tested. Other than this incident I've never discharged them more than 30%.
Assuming my batteries load test good does anybody have an idea what happened?
It seems like the house batteries either weren't charged in spite of being on shore power and showing 14+ volts Tuesday morning or they fully discharged while I was driving 80 miles to the camp spot.
My system in addition to the batteries: Magnum 2800 watt inverter/charger, 840 watts solar with Morningstar controller, Victron shunt type battery monitor.
I ended up running idling the coach engine for about half an hour which put enough charge into the house batteries to start the generator. I ran the generator for an hour or so which brought the house battery voltage back up to 13+ volts. I didn't use any power over night except for a few minutes of LED lights. First thing in the morning the house batteries were down to 10.9 volts. Once the sun was up the solar started to slowly bring the voltage up but was still not enough to start the generator on Wednesday night.
Again, I ran the coach engine long enough to start the generator and then ran the generator all night so I could also run the furnace. I didn't have enough propane to do that for another night so I came home. Figuring that I have a failed battery I've removed them from the coach but they all test out good with a volt meter. These are gigantic 800AH Lifeline 6V batteries. All 4 measure 6.51v-6.45v. Today I will take them to my local battery shop and have them load tested. Other than this incident I've never discharged them more than 30%.
Assuming my batteries load test good does anybody have an idea what happened?
It seems like the house batteries either weren't charged in spite of being on shore power and showing 14+ volts Tuesday morning or they fully discharged while I was driving 80 miles to the camp spot.
My system in addition to the batteries: Magnum 2800 watt inverter/charger, 840 watts solar with Morningstar controller, Victron shunt type battery monitor.