Originally Posted by 16ACE27
If you are plugged into SP there should be no draw on either the house or the chassis batteries as the converter should be charging the house batteries at 13.1+ VDC and the Trombetta should be closed to also allow the converter to charge the chassis battery at the same voltage.
If you are not plugged into SP the Trombetta should be open (de-energized) and the batteries isolated from each other.
You will only here the Trombetta close and open when using the Emergency Start switch if NOT plugged into SP. When plugged into SP the Trombetta is closed most of the time.
I didn't think shore power charged the chassis battery. On my 2018 Chateau it doesn't seem to.
On a class C E450 the Trombetta is located under the coolant reservoir in the driver's side rear of the engine compartment. I'm not sure if it's in a similar location on the ACE.
When I push the Emergency Start switch I do hear the click of the Trombetta energizing. It also energizes a few seconds after starting the engine so that the alternator charges the house batteries.
My Trombetta failed and was not allowing the alternator to charge the house batteries. The symptoms were that the house batteries were not charging and I was getting a low voltage error on the levelers. I thought the batteries were going bad, but new batteries didn't fix the low voltage error. The Trombetta was energizing, but there was a voltage difference between the input and output terminals. This difference shouldn't be more than about 0.2 volts.
I'm not sure how much of this info is relevant to your problem, but hopefully some of the infowill help you troubleshoot your issue.