LP gas detector keeps beeping

Some propane detectors are connected to solenoids that switch off the propane if the alarm goes off or the wires are disconnected. To know if this is the type, you will have to give us the make and model of the detector. I have one that goes off, and it has been checked over and over. There are no leaks, no low battery and no bad detector. In my case, it is almost certainly the dogs (yes, it is sensitive to methane). I found the only consistent method to be sure it doesn't go off is to run the ceiling vent fan with the air flow blowing out. Oh, "connecting to an AC source" means plugging in to an electrical hookup. If the trailer is in the driveway, you would find it very useful to put an electrical adapter or outlet in the garage door so the RV can be plugged in to prepare it for a trip, and you don't need to be electrically savvy to do this: just be sure you don't use more current than the circuit you plug into is capable of carrying.