I have the camper in my sig that has two A/C units and 50 amp. I did a test when I first got the camper. It was July 4th and 90* + and wanted to see how much propane the units would use. I ran both A/C units on high for 24.5 hours on 3 -30 pound tanks and used whatever I wanted to in the rig. I did it to break in the genny as well. Maybe this will give you an indication. Yes, it is expensive to use the propane. Do a search on here and on RV.Net and you can find propane usage charts.
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