Does the system automatically charge the chassis batteries when plugged in? The inverter charges the coach batteries, but I don't see any system to charge the chassis.
Most coaches of our vintage don't automatically maintain the the chassis batteries. You can add various ways to do so. A quick search of the forums will turn up a number of threads. Try "trik-l-start." Or just "maintaining chassis batteries " for lots of ideas.
Rich
Searching the Forum for "trik-l-start" may find threads with leads to other similar products, but the actual Trik-L-Start product is no longer available. LSL Products made the Toad-Charge, Trik-L-Start and Amp-L-Start devices. The owner of LSL Products died in October 2022. Production ceased and products were shipped out of existing inventories to fulfill orders until the supply finally dried up.
Other companies make products that serve the same purpose. Some examples would include the Magnum Battery Combiner or Xantrex Echo Charger or Victron Cyrix-CT. I am bored this morning so I looked up the links.
Smart Battery Combiner | Magnum Dimensions (https://www.magnum-dimensions.com/smart-battery-combiner)
Xantrex | Auxiliary Battery Charger (https://xantrex.com/products/accessories/auxiliary-battery-charger/)
Cyrix Battery Combiners - Victron Energy (https://www.victronenergy.com/battery-isolators-and-combiners/cyrix-battery-combiners)
I made my own with 2 forty amp diodes that worked well. I will take a picture of it later today.
I use this for all winter storage
BatteryMINDer® Model 128CEC2: 12V 2/4/8 AMP Charger-Maintainer-Desulfator & Lithium Charger Maintainer
It has settings to work with any type of battery you use in the coach
It works amazing
I use my battery boost switch (if your coach has one) to connect all the batteries for 24 hours every month while in storage. That keeps the chassis batteries charged.
Sorry it took so long but my computer wouldn't upload the picture and then I couldn't find
the post. I used this for a few years and it worked great but I change my isolator to a Blue Sea
Systems remote battery switch solenoid.
I sold my similar coach about a year ago, but for years I just put a BatteryMinder into the cigarette lighter plug on the dash. Make sure to distinguish between the house ACC 12v plug and the chassis 12v plug. Kept the chassis batteries perfect and the house batteries were maintained by the onboard charger as you noted. I simply plugged the coach into a 15A duplex circuit in the garage and turned off the battery disconnect while in storage. I think the BatteryMinder mentioned by Peter in Reply 4 would work great, but I cheaped-out and went with a BatteryMinder 2012-AGM. Just stay below 10A when charging through the cigarette lighter plug.
I have had almost perfect luck trying to keep engine batteries charged. Did you read the almost? One mistake and then running the chassis batteries down affects their life quite a bit.
My understanding is that new coaches use auto combining relays. If either battery bank is being charged then the other bank is auto connected.
As my coach is outdoors and has no external power available I had a blue-seas ACR wired in. Auto connecting relay.
Then 1100 watts of solar. And a solar controller. And a battery temp system. And a newer inverter.
After my wallet recovered from the zillion dollar bill it is an old rv'er satisfaction to walk up into the coach and both battery banks are at 100% correct full charged voltage based on the house battery banks actually temperature.
This was an rv'ers dream 40 years ago. In my case adding new gel batteries(3) added to the dream fulfillment.
In my next life I might have an rv with the new fangled li-ion complete setup. Double or triple capacity.
My draws are not that high. Yet.
Why all the elaborate installs? I had trikl-chargers fail internally due to too high of a load. Green light on. No power. Make sure when you store your coach that all batteries are fully charged unless you have good shore power and a connection to the chassis batteries.
In my case I only need the sun to shine. Harder to interrupt