I understand that this subject has probably done to death, BUT I haven't been with you for long. I have a twin small bottle Gaslow system in my van and I found out when I got home from Lincoln today found that I was low on gas in the second cylinder. This has been turned off at the tap and I thought it to be full from the last fill. I have bought a level sensor at the show, and it shows that the level is only three inches up from the base on that cylinder and nearly empty on the open cylinder that was being used. I went to the Gas station in Dover to fill up and it took 10 litres to fill but the second cylinder is still empty, the level is the same, the in use cylinder is almost full. Is it possible that the float shutoff valve has stuck closed and would a drop or bang move it? Alternatively do I need to push the garage pump button for longer if it only puts in at 10 litres at a time and it had not had long enough for a second pump. I am confused as I thought the filling system MUST fill both together as they are connected together to the inlet. Do I need to get another bottle? I need to know about this as I have to run the heating off the system when I go about in winter. Wifey suffers from the cold and refuses to get up if it is cold.