A cautionary tale! - we started packing up our Bessie E795 today for a trip (hadnt used her since early August) and when we opened the door the inside area absolutely stank of rotten eggs. We have had drain smells before but nothing like this. £10 poorer on drain unblockers, bleach and air fresheners the smell remained. We suddenly remembered we had read somewhere that the smell of rotten eggs can be caused by an overheating battery so we investigated both van batteries - the leisure battery (6 years old) was very, very hot and absolutely stinks of rotten eggs. Probably would be very bad for you if you slept in the van with the smell. So off to buy a new leisure battery and pleased to have found out what the problem was.