Hello, I've got an issue with my two 85amp chassis batteries in my Damon Daybreak 95'. I left them to charge with the RV battery charger for 24hrs and both of them them seemed ok, went up to 13.25v. Next time I left them on for 48hrs to see how this will effect them and they got flat, down to 11.4v. Is there something I'm missing? It is still the original 95 charger so maybe it's faulty? Or perhaps something else is draining the chassis batteries that I'm not aware of? I don't drive my RV at all right now, not till I get the licence so I'm also searching for a way to keep the batteries in good working condition.
You will need to determine if the batteries are good or bad. You can bring them to your local auto store to have them tested there but first you should perform some tests, checks, charging and maintenance.
You will need a digital multimeter $30-$50.
Before charging check the water levels in the batteries. If any of the plates are exposed, add just enough water to cover them and no more. Use distilled water. Distilled water can be found at most grocery stores.
Try to read the date of manufacture on the batteries. Age is important. Anything over 3 years probably should get replaced based on the age and the assumed use up till now.
Readings at the batteries with the converter charger ON and charging should not be any less than 13 volts and should not exceed 14 volts.
After charging the batteries, fill the batteries with distilled water just up to the bottom of the vent hole.
You should have a "salesman switch" by the entry door. That switch will disconnect the batteries from the house and usually will allow charging from the converter charger. Set that switch so that no power is getting to the house and confirm that the batteries are still charging with your digital volt meter.
If you think you may have a converter charger problem, pull the batteries from the motorhome and use an axillary charger. Follow the same process and have your local auto parts store load test the batteries.