You mentioned the parasitic load of your converter, but then you also mentioned that you had turned off all the circuit breakers except for the air-conditioner one. Are you suggesting that the converter is remaining on despite breakers being off?
If indeed your converter is still on that could certainly be the source of your problem.
You've also confirmed that your electric hot water tank is indeed isolated as well, correct?
It certainly sounds as if you're on the right track by switching off circuit breakers to try to isolate the air conditioner, but given as how some travel trailers are wired in such a bizarre fashion today it wouldn't surprise me if there's still a phantom load somewhere that you might be missing? With all of the breaker set in the same position that you've been doing this testing, the generators in Eco m ode, and the air conditioning switched fully off, when you plug the trailer into the generators is there any sort of RPM bump or sudden load (even for a split second) evident?
