Go get a 50-foot or longer extension cord and run out to the truck from the garage and plug in a oil-filled heater...
If you are going to be doing this alot then you probably should pick up a good HD 50-FOOT 10-GAUGE (10-3) Extension cord and a RV30A-15A LONG Adapter (WALMART) and then connect your trailer 30AMP SHORE POWER Cable to this setup plugged into a garage 120VAC receptacle. Having this setup just makes it easier to run an 12-0VAC extension cord inside your trailer. You can plug the oil-filled heater above into one of the trailer 120VAC receptacles inside the trailer now. I would not set higher than a #3 setting on the oil filled heater.
We do this all the time with our setup at various places we go to. Can run everything in our 30AMP trailer but if running the air conditioner or high wattage microwave we have to just have that unit turned on otherwise it will trip the garage breaker.
Do not use these small 30A-15A adapters as they will get hot on you over time and may do damage to your connectors.
This is what you DON'T want to happen using the small RV30A-15A adapters
Roy Ken
