We had the same problem this past January while we were in Florida. It went off 3 different times at 3 different campgrounds. We could not smell any gas either. When we got home, we took it to the dealer. He checked the alarm, checked lp with manometer, used a sniffer, soap bubbles on all the fittings and checked the battery. Nothing.....Said it could have been some other chemical setting it off....We've used it a couple times since then, and no alarm.....One of those mysteries.....