Users should speak with a licensed oil heat technician about replacing an oil tank if it has uneven legs, shows dripping or signs of leakage around the valves or filter or is several decades old. Tanks with weeps, wet spots, rust and extensive denting may also need replacement.
Individuals should also contact a technician if an outside tank is dark in color, the gauge is cracked or the oil lines are covered by concrete if underground or encased in a strong tubing if above ground. Oil tanks generally begin corroding from the inside out due to sediment and moisture gathering in the tanks over the years, so users cannot always tell whether a tank needs replacing without expert advice.
Although bad oil tanks may initially begin leaking oil through a pinhole-sized crack, they may also fail all at once, spilling large amounts of oil from the tank. This can lead to an expensive hazardous waste cleanup if the tank is outside. It can also leave a lingering odor if the spill is contained in a concrete basement. Older oil tanks tend to have a thick layer of sediment on the bottom of the tank that can be drawn into fuel lines if the oil level gets too low, which can potentially clog lines and damage the furnace.