I believe you are taking about adding a heat pump to the AC unit. Yesterday I did some research on that and I can add it to my unit. However the heat pump does not function properly below 40 degrees. Again that was very disappointing to hear that.
No, I'm not. I'm not even sure it's practical to convert an air conditioner into a heat pump.
I'm referring to heat strips that many ACs offer as an option. They work essentially at 100% efficiency no matter what the outside temperature is.
Dan, look at the website for your specific air conditioner first -- whichever brand you have.
In the specs you may find reference to an optional heater assembly similar to the one attached for a Coleman. I don't know for certain if these can be retrofitted after initial installation, but expect they can be. Your dealer can probably confirm if it's possible, and quote the cost.
I've experienced a heater that wouldn't keep the burner on for more than maybe a couple seconds at most. Two of the vents were closed and once those vents were open the heater worked fine. That RV must have had something about the airflow causing the burner to shut down.
So maybe a test of compatibility might be to close off a couple vents to see if the heater still works as I doubt the comfort system unit would introduce restriction greater than what a closed vent or two would.
I quite like the idea of the ducted coach heater having an electric option. Just like the refrigerator and water heater.