An oil filter should be installed on the fuel line in between the oil storage tank and the burner. The oil filter will likely be of a cartridge-type. It is recommended that the filter cartridge be changed at least once a year. The filter body should be cleaned before a new cartridge is installed. A cartridge-type oil filter prevents sludge in the oil clogging the fuel pump or the oil burner nozzle, which would cause the system to fail.
The fuel supply tank is sometimes called the oil storage tank. The fuel supply tank holds the fuel oil. It can be located inside or outside. It could be located above or below the level of the heating system. If located outside, the tank could be underground or above ground.
The tank is connected to the fuel pump of the heating system directly with a fuel line.
There are one-pipe systems and two-pipe systems that connect the tank to the heating system. When you see a one-pipe system (where only one fuel line pipe is connected to the burner assembly), the tank is usually installed in the same location as the heating system, such as both being located in the basement. When you see a two-pipe system (where there are two fuel line pipes), then the tank is usually located outside, the distance between the tank and the heating system is likely long, the tank is located vertically above the heating system, or the tank can not use gravity to move oil to the burner.
A shut-off valve should be installed on the suction line. You may find a valve installed near the tank or near the heating system.
In general, the filler pipe should be a minimum of 2 inches in diameter; the vent pipe 1 ¼ inches in diameter. The pipes should be made of wrought iron. The oil supply lines between the oil supply tank and the oil burner should be made of copper tubing.
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WTF is fuel filter??? Why would I want a fuel filter??? I am 60 miles as the nuetron flies from the Biggest Nuke in the States, the fuel comes through wires here. 
You got a deal on INACHI Dosimeters? 