
We need to run Cocoon’s air conditioner on sweltering humid hot summer nights to get a restful night’s sleep. After a lot of research, we bought a generator that can power the Airxcel Mach-3+ when boondocking.

We chose the Champion 2500W Dual Fuel generator. It is economical, quiet, lightweight, and burns both gasoline and propane.
It provides just what we want and nothing more. It has enough power to run one large appliance when off-grid.
Fuel
Our primary bulk fuel is propane when we have it. It is nice to have the option to burn gasoline if we can’t readily get propane.
We keep some gasoline in the generator tank to get us between propane tank refills if we run out. Gasoline is also handy to help prime the generator when propane-priming is slow.
Casita Measured Load

These are the power measurements with the Casita air conditioner running and the generator burning propane.
I used this meter for the measurements. The outside temperature was 74 degrees, and the battery was charged.
The baseload for the trailer was 60 watts. The baseload is the power converter running the fixed 12v loads in the trailer with all devices in the off state.
A/C Setting | Power (watts) | Voltage (volts) |
Baseload + Off | 60 | 122 |
Baseload + Low Fan | 319 | 122 |
Baseload + High Fan | 348 | 122 |
Baseload + Low Cool | 1,195 | 120 |
Baseload + High Cool | 1,272 | 120 |
Baseload + Low Heat | 1,739* | 115 |
Other Casita Loads
These are some additional large-appliance loads I measured. Of course, the refrigerator and water heater would be running directly on propane when it is available.
Description | Power (watts) | Voltage (volts) |
Baseload + Microwave | 1,407 | 120 |
Baseload + Refrigerator | 219 | 122 |
Baseload + Water Heater | 1,472 | 120 |
Champion 2500W Dual Fuel Specifications
These are the manufacturer’s specifications for the generator. Note that the rated starting power is the same for both gasoline and propane.
Description | Gasoline (watts) | Propane (watts) |
Starting Power | 2,500 | 2,500 |
Running Power | 1,850 | 1,665 |
Mach-3+ Specifications
These are the manufacturer’s specifications for the air conditioner. Note that the measured power was well below the specifications. Likely because the ambient temperature was only 74 degrees and the trailer wasn’t in the sun. I hope to post some higher-temperature readings in a future article.
Description | Power (watts) |
Standard Conditions | 1,400 |
Desert Conditions | 1,695 |