[flybouy]

If you ran out of lp gas and changed tank over manually (turned valve on regulator to full tank) three things come to mind.
First - air in the line. Turn all burners on stove top on and wait a min. or so. You should hear and smell gas. If gas is not present then
Secondly - turn gas valve off and all gas appliances off. Then open tank valve SLOWLY. If you open the valve too rapidly the valve can "see" that as a leak and shut it's self off. Repeat first operation. If still no gas then
Third - change hoses on tanks. If regulator is bad the gas line to the regulator that was working should still work,.