2009 Thor Four Winds Citation 24SA - Batteries

We have a Sprinter Thor 24HL, 2017.

Our original coach battery was switched out for a couple of Deka 31 flooded batteries. The original battery was in bad shape due to low charge and lack of use just sitting on the RV dealers lot.

Our coach batteries work as a two battery banks. We added the second battery, for us it was a matter of a battery strap and a two cables to join the batteries together. They have worked well.

We can charge our batteries 4 ways. Via the Sprinter engine, the generator feeding the inverter/charger that is build into the coach, the 120v cord plugged into the grid and finally via solar that we have added. Its all automatic.

If you coach is like our coach, your coach batteries are under the entrance steps. If so you will be limited to 12v batteries. There is nothing wrong with 12v batteries they will work quite well.

I would have your battery tested, most of the national auto stores will do it for free. Replacement, we went with flooded, if I had it to do over again I would probably go with AGM, they are about twice as expensive, but I do have to shift my flooded batteries around to check the water level and refill. Not necessary with AGM.

FWIW, if your coach battery gives out, you may be able to start the generator using the Sprinter engine starting battery, start the Sprinter engine, operate it about 2000 rpm's and that should give you enough power to start the generator, then you can shut down the Sprinter engine and use the generator for charging the battery if necessary. We have to start the engine because of the battery cut off switch between the coach batteries and the Sprinter starting battery.

Good Luck

Rick

As per owners forum, the chassis batt on your rig charges off the alternator and the coach batt charges off the converter while plugged into shore power or the genny.
In case you fire up the genny and you don't have power.... There is probably an on/off switch when using the genny vs shore power to power up the rv. On my rv I don't have a switch, I have to plug the genny into the 30amp receptacle that I also use to plug in my shore power.




You could use an inexpensive volt meter to test the batteries. Then start the rv and see if one or both the batteries charge.
With the rv off those batts might read 12.6v. As soon as you start the rv, that voltage will jump up to 13 - 14v . That way you'll know for sure if the alternator is charging one or both. :)

If the set up is not what you desire, then you could always add an isolator module under the hood that will charge both batts when driving and only draw down the coach batt when camping. It acts as a one way gate so you don't kill both batteries while camping.

http://www.thorforums.com/forums/f8/chateau-sprinter-chassis-battery-issue-704.html


Have those batteries load tested. You might need to buy new if its not holding a charge. That way you know what you have. If you decide on 2 new coach batteries , buy the same size and same age (checks the dates of mfg.) that way you will know they are in balance and will charge and discharge at the same rate without one weak batt pulling down the stronger batt.
Some people run 2 -12v batts and some desire 2 - 6v batteries in series to = 12 volts. Research that to make your decision.

check water level in batteries, also look for a tag that shows how old the batteries are. while your checking things look and see how old the tires are. even thow they could look great they could be the orginal ones.