I see wmtire beat me to it. The long rod is an anode rod. It fits into the bottom of you HW tank, on the outside of your trailer. If you have the plug in now, take it out to make sure you have an anode rod and to drain possible anti freeze in it. If the pink stuff is in there, you should flush out the tank real good. There really shouldn't be any anti freeze in there if it was drained properly. Now if the anode rod is there, screw it back in fairly tight. Don't overdo it. Fill it up with water. You should have a rocker switch at your control panel that you turn on to light the HW heater, making sure the propane is turned on. It might take a bit for the air in the line to be forced out by the propane. Be patient. It might turn red when you turn it on and may blink a few times. You might even hear a clicking noise, which is the heater trying to light. Just make sure you have water in the tank before you try the electric side of the tank or you will burn out the electric heater in a matter of seconds.