2019 24D DC to DC Charger Installation

[tpc66]

Does anyone have a link to instructions/advice or a video on installation of a DC to DC charger in their Winnebago? I have a 2019 Navion 24D on a 2018 Sprinter chassis and recently added Lithium batteries. I'm pretty far along with it but everything I'm reading says I should install a DC to DC charger to protect the alternator.

I've watched a bunch of youtube videos but most people gloss over the physical install and wiring and go straight to "look at how great it works." I need some details...

I've looked at the various models and they seem straightforward - I'm just trying to figure out the best place to install it with a minimal amount of cabling changes.

Thanks in advance!

Tom

[SafariBen]

Do you have the DC-DC that you're going to use? or have the directions available online? Have you found the connection point between the chassis and the house batteries currently? that will be a logical place to put the DC to DC, or at least in that same circuit.



Since you haven't read it yet, You do NOT need a DC to DC charger, you should have SOME way to limit the current going to the batteries, but there are easy ways to do that.

[tpc66]

Originally Posted by SafariBen

Do you have the DC-DC that you're going to use? or have the directions available online? Have you found the connection point between the chassis and the house batteries currently? that will be a logical place to put the DC to DC, or at least in that same circuit.



Since you haven't read it yet, You do NOT need a DC to DC charger, you should have SOME way to limit the current going to the batteries, but there are easy ways to do that.

I have not picked one out yet - looking at all of the obvious brands. Truthfully, I'd be fine with just putting a cutoff switch so that the alternator can be stopped from charging the house batteries.

The battery maker (Epoch) "suggests" a DC to DC charger.

I am wide open to opinions at this point - just can't get a clear idea and direction of what I want to do.

[SafariBen]

A cut off switch should be coupled with enough resistance so the voltage drop from your alternators output voltage, to the Li lowest voltage level, will not draw more amps than you want, or at least have a shunt to monitor that amperage so you can decide when to shut it off. Li have low resistance, which is why they are capable of overloading alternators, but they have higher voltage also, so it is not difficult to limit the current.



The other side of the equation is the alternator may not charge the Li ENOUGH to balance them. This is easily done with solar or a Li compatible shore charger, "every few months", not needed every day, week or month even.

[d23haynes57]

Did the Navion even have engine alternator to House battery charging capability? Many of the Sprinter vans have specific requirements for where to connect and are often limited to 40 amps.

[tpc66]

Originally Posted by SafariBen

A cut off switch should be coupled with enough resistance so the voltage drop from your alternators output voltage, to the Li lowest voltage level, will not draw more amps than you want, or at least have a shunt to monitor that amperage so you can decide when to shut it off. Li have low resistance, which is why they are capable of overloading alternators, but they have higher voltage also, so it is not difficult to limit the current.



The other side of the equation is the alternator may not charge the Li ENOUGH to balance them. This is easily done with solar or a Li compatible shore charger, "every few months", not needed every day, week or month even.

I'm good on the solar and the converter for balancing - just want to protect the alternator. Thanks for the input - still digging and learning but a solution is near!

[tpc66]

Originally Posted by d23haynes57

Did the Navion even have engine alternator to House battery charging capability? Many of the Sprinter vans have specific requirements for where to connect and are often limited to 40 amps.

That's a great question! I just wrote Winnebago and they immediately responded saying that my unit does charge the house batteries from the alternator.

I haven't put a meter on it yet with the engine running - I was more focused on getting the solar and converter setup to do the initial charge. Now I just want to ensure that I don't fry my alternator once we hit the road.

[J_Lambert]

This page should cover it https://www.viewnavion.com/mods/lithium-batteries

This website is a great one for mods for views/navions

[tpc66]

Originally Posted by J_Lambert

This page should cover it https://www.viewnavion.com/mods/lithium-batteries

This website is a great one for mods for views/navions

Yep, I had used that webpage is one of my references. Everything’s good now, I had to replace the solenoid as it was causing zero voltage on the output. Once I did that everything’s working great.

[dkoldman]

Originally Posted by tpc66

Yep, I had used that webpage is one of my references. Everything’s good now, I had to replace the solenoid as it was causing zero voltage on the output. Once I did that everything’s working great.

The more research the more confusing it becomes. I made the Li conversion my self about a year ago and total cost was about $500,Add $400 for a 300ah Lithium battery and I am now like those that only say how great it works. I did mine step step over a 3 month window.

Note: I am not saying you should do this, nor that it is the best method, just what I did.

I started with AGM batteries for house that was an RV that was 5 years old. I am original owner.

Step 1 - I put a switch on my trombetta so I could turned it off / on. Effectively disabling the charging. Once verified working with no issue, I left enabled because I had AGM batteries.

Step 2 - I bought a new Progressive Dynamics Converter. Sold my OEM one for $125. The new one works with any type of profile plus it had a remote to see the charging profile status. I put it in the AGM profile and ran about a month, it was exact same footprint as the OEM one so it was very easy to do.

Step 3 - I bought the Victron 50 amp DC to DC. Don't buy the Victron 30 amp, pay more to get the 50 amp. I bought Victron for future expansion with Victron app. I am glad I did. Now you ask how to install the DC to DC and it is very easy.

Find close place for DC to DC batteries, Positive from chassis will go into input of DC to DC, the Output will go to positive on House batteries, then connect the ground to closest source or ground on battery house battery. I software configure the Dc to DC for AGM batteries

Step 4 - I purchased a 300ah Lithium battery. I went from 2 125ah AGMs to 1 300ah Lithium. After installing...

Step 5 - Flip the switch to disable the Trombetta, change profile in Converter and DC to DC to Lithium

It was very easy.