Originally Posted by DustyandKaren
Hi we have a 2014 Thor and our 2 house batteries have gone. We have only used it for 2 summers and put them in store mode when not using. When camping we are normally at KOA so plugged into power, When plugged into power, and the house batteries in use does that overcharge them, I am told yes and I am told no, Also how often have you had to change yours. I am also told that the new models of RV that the life of house batteries is 2-3 years, where olders ones can go 5-8. Input, thougts, things we should look for or be doing that maybe we are not, Not nice to have to pay 400 every 2 years for new house batteries has to be a way to extend t heir life. Happy RVing all.
You say you have a 2014 Thor, but you don't say what it is. If it's a higher end Thor motorhome, it likely has a multi-stage charger, which should not overcharge the batteries if left plugged in all the time. We got about 6 years on our original pair of 6-volt GC batteries in the motorhome we used to have. We're full-timers and are plugged in ALL the time except when on the road. The motorhome had a 3-stage charger.
On the other hand, if you have an entry-level Thor TT, you may have a single-stage charger which will overlarge the batteries.
The other thing you mention is putting the batteries in store mode. Leaving lead-acid batteries in a low state of charge for long periods will also be detrimental to their longevity. Lead-acid batteries will discharge by themselves over time, and leaving them sitting in the RV all winter is bad for them. Before we went full-time, I used to take the batteries out of the RV in winter, sit them on my workbench, and connect them to a charger periodically.