See if this helps any. To help prevent the draining over time, I turn the battery disconnect off when not camping. As if I do not the propane detector will drain the battery down by itself.
I'm assuming you have wet cell batteries. To your deep discharge, something you can do to help is to desulphate your battery. They sell battery minders that have this feature or some of the more higher end battery chargers. It boosts the voltage to 14 volts which burns off the sulfate that builds up from discharging.
And if you are going to dry camp and want to come as close to 100% full charge, this desulfating will help get you there. If you do not desulfate every so often, over time you will start loosing the ability to reach full charge.
There are a few brands of the battery minders out there with this desulfation feature. I did just get one of these.
I also have the $8.00 float charger from Harbor fright like nickster60 stated that I use on some of my other batteries.
Now to buy new or what. He is a thought, get a battery minder with desulfation. First charge the battery up, then put the battery minder on it. It may take a while to desulfate the battery but once done, let the minder stay connected,. They then go into float mode. Then come spring, take it to a garage and have them load test it. They can tell you the statis of the battery. Some Advance auto stores do this for free. If the battery is good, your good. If it’s not, well you know. And using the battery minder all the time when not camping will keep you up at the 100% charge area and desulfate as needed.
Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC
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