[Richard]

The trouble shooting is somewhat guesswork because some baseline info is needed. The state of batteries before the Tom's charger was applied is forever lost.

However it is not too late to help troubleshoot the situation before tearing into the inverter charger.

Let's start with this info. Unplug the coach. Unmerge the batteries. Measure with a voltmeter the voltage at the chassis and house battery terminals. What are those voltages?

Now, plug the coach in, or start the generator, either method should activate the charger.

What is the voltage now at both the chassis and house batteries? Does the charger panel in the coach say it is charging? If so, how many amps does it show charging.

If the charger is working properly, you should see a higher voltage at the house batteries, than you measured without the charger.

If you have some sort of echo/trickle setup you should see a voltage rise on the chassis batteries.

If I remember correctly, Newell wired the Xantrex controller so that Bank 1 was the house batteries, and Bank 2 was the chassis batteries. That doesn't mean that the Xantrex was wired to charge the chassis batteries. You only have monitoring capability on the chassis batteries from the Xantrex.

Please report on your voltages, so that we can help you.