2018 Thor Citation House/Chassis Batteries charging

nc-rv

Advanced Member
Joined
Nov 20, 2024
Messages
36
Location
Charlotte
I’ve searched for a few hours on and off and threads are back and forth on this.

Chassis batteries are low, was hoping the isolator which Thor sent a diagram and claims this mode has. However, house batteries are charging at 13.7ish, but chassis batteries aren’t charging.

Start the unit, alternator charges at 14.1 and seems the house batteries are charging.

Thor stated the isolator is in the battery compartment at the steps but I don’t see it. Looking at the chassis battery, underneath, one positive cable is coming out and goes to the alternator.

I’m about to head out and see if it may be under the drivers seat like some other models I’ve seen.

Does anybody own this model and. Know for sure? I want it to charge both ways and have a bypass switch in case one side is depleted.

In the past I use the Blue Sea but not sure there is enough room. I’ve seen some threads on a bird haven’t looked into.

This unit doesn’t have an inverter so I’m going to look into adding one and potentially replacing the 27 house batteries with lithium to run the TV, maybe AC sparingly in the mountains if need be.

Also, there are solar panels on the unit but I’ve yet to find any sign of a solar panel or anywhere to monitor if it works.

Again starting this thread in hopes others out there have went down this path with this model, or update it as I go along for others.


Summary:
  • Where is the battery isolator on this unit?
  • Does it allow the converter on shore power to charge the chassis batteries. If not, what did you use to allow charging both ways?
  • Solar converter or components. (This has a firefly multi panel and nothing it. The last page shows a bedroom battery but think that’s used.)
    Upgraded the batteries to Lithium, if so which ones and was it worth it
    Did add an inverter for at least the receptacles and microwave?
 
I assume you have the Sprinter chassis?
If so, you have an IRD/Trombetta battery combiner/isolater.
The IRD only allows the chassis system to charge the house system, not the other way around. That's a MB requirement - no external power source to the chassis DC system.
 
I assume you have the Sprinter chassis?
If so, you have an IRD/Trombetta battery combiner/isolater.
The IRD only allows the chassis system to charge the house system, not the other way around. That's a MB requirement - no external power source to the chassis DC system.

Thanks.

Any idea where it’s at, under the drivers seat. Don’t think it’s in the battery compartment like Thor states.

Have you changed it out? I’ve seen concerns about the alternator charging the other way but non with the converter charging the chassis. Going to suck trying to jump this sprinter should the battery run low and also the gen seems to run off it.
 
Thanks.

Any idea where it’s at, under the drivers seat. Don’t think it’s in the battery compartment like Thor states.

Have you changed it out? I’ve seen concerns about the alternator charging the other way but non with the converter charging the chassis. Going to suck trying to jump this sprinter should the battery run low and also the gen seems to run off it.

I have no experience with the Sprinter chassis, but on other Class Cs it's usually under the hood on the drivers side. Tracing the positive side of the battery cables should lead you to the Trombetta solenoid.
 
I have no experience with the Sprinter chassis, but on other Class Cs it's usually under the hood on the drivers side. Tracing the positive side of the battery cables should lead you to the Trombetta solenoid.
So far I just see one on the outside of the battery compartment and it goes to the alternator then looks like starter. Few cables look to go under the seat so in the process of trying to get in there.
 
Getting the drivers see off, the isolator is under it. Also, looks like the one way version.
 

New posts

Try RV LIFE Pro Free for 7 Days

  • New Ad-Free experience on this RV LIFE Community.
  • Plan the best RV Safe travel with RV LIFE Trip Wizard.
  • Navigate with our RV Safe GPS mobile app.
  • and much more...
Try RV LIFE Pro Today
Back
Top