At JC Heating & Cooling we understand heating oil tanks
Fuel Oil Storage tanks designed and constructed to S602 or UL 80 will provide years of trouble free use if installed and maintained properly. An understanding of the ways these tanks can fail will greatly improve the quality of installations.
There are three basic modes of failure for heating oil tanks. They are manufacturer defects, mechanical damage and corrosion.
The most significant manufacturing defect is a poor weld. Quality control and quality assurance techniques are used to reduce manufacturing defects. Welding procedures are continuously being upgraded. Testing methods are also being improved. All Kerr heating oil tanks are leaked twice during the manufacturing process. The heating oil tank you buy today is of higher quality than the oil tank you bought last year due to continuous improvement process.
There are many steps that can be taken by the installer and the homeowner to greatly reduce the likelihood of mechanical damage. The fuel oil tank must be placed properly on reinforced concrete pads and in some cases fastened down. Vulnerable areas of the tank such as the gauge, the valve and the oil line must be protected. The fuel oil tank should be regularly inspected for vandalism or inadvertent damage. The fuel oil tank should be protected from snow and ice. All of these can be accomplished at little cost.
Nearly all fuel oil - heating oil storage tanks rust from the inside out. Moist air condenses inside your fuel oil storage tank, contributing to a sludge that accumulates at the bottom. This can lead to internal rust or corrosion which can cause leaking. Outdoor fuel oil storage tanks are even more prone to condensation due to daily temperature changes.
Corrosion is the most common cause of tank failure. There are two distant types of corrosion failures, short term (1-years) and long term (5-30 years). In their natural state metals exists as oxides, hydroxides or sulphides. Energy is required to divorce the iron from the oxygen in the blast furnace. The manufactured process for steel can be described as:
Iron Oxide + Blast Furnace + Bessemer + Mill = Steel
Sheet Steel + Electrolyte = Iron Oxide
Unfortunately, fuel oil tanks can provide the right conditions for corrosion. The energy that drive the corrosion reactions is the same energy imparted to the steel from the refining process.
Electrochemical corrosion of metals requires an anode, a cathode and an electrolyte. The anode has more stored energy and will therefore corrode to attain a lower energy level. The cathode has lower stored energy and therefore will not corrode. The electrolyte completes the circuit for a galvanic cell. In the galvanic cell ions of steel travel through the electrolyte and are deposited at the cathode. The cathode is large relative to the anode and pitting corrosion will occur.
If there are no vast differences between the size of the anodic to cathodic ares uniform (long term) corrosion will occur in steel. The uniform corrosion leads to a loss of metal of from 0.0025" to 0.005" per year when steel is submerged in seawater. Fuel oil itself is not a good electrolyte so the corrosion rates should be significantly lower than that for seawater. This accounts for the long life of greater than 40 years for some tanks.
Why do some tanks corrode through in less than one year while others take 20 - 30 years? The answer is early exposure to an electrolyte. Newly manufactured tanks have a coating of mill scale. This mill scale is cathodic relative to the base metal. During manufacturing small cracks appear in the mill scale. The large cathodic mill scale islands, the narrow bare steel cracks and the electrolyte from a galvanic. Because of the tremendous imbalance in size between the cathode and the anode, very rapid corrosion can take place. Over time the interior surface of the tank becomes electrically uniform and the occurrence of pitting corrosion is greatly reduced.
There are two schools of thought concerning the formation of electrolytes in the tank, bacteria and chlorides.
Bacteria exist in the air, in the soil and are present in even the cleanest looking fuel. They can exist in a latent form for many years. When conditions are suitable they will grow and multiply. They can double in number every 30 minutes and will multiple to one million in 10 hours. These bacteria live in water and feed off fractions of the fuel. Their metabolism produces hydrogen, carbon dioxide, as well as high molecular weight, carbon rich residues. This biologically active sludge is corrosive to steel.
Every fuel oil tank failure we have investigated has had high levels of water soluble chlorides in the sludge. The chlorides could come from constant "breathing of ocean air. Salt water used as ballast in tankers may contaminate the fuel.
Whether biological contamination or water soluble chlorides or both are the problem, water is the common factor. If we can eliminate the electrolyte we can stop the corrosion. Water can enter an oil tank in many ways. Transfer of water and sludge from the old fuel oil tank, is one of the most common. Water can enter the fuel oil tank through broken gages and or missing caps or simple condensation. Outdoor fuel oil storage tanks are even more prone to condensation due to daily temperature changes.
The solution to the problem is to keep water out of the fuel oil tank. Since this is impossible, we must get rid of the water with a bottom outlet. At JC Heating & Cooling we can add chemical additives to absorb the water. Any water produced by condensation will then be consumed by the burner.
Anecdotal Observation: Outside fuel tanks fail more often than inside fuel oil tanks. Additives and tanks with double bottoms is the secret to longer oil tank life.
If your house is more than 10 years old, it may be time to check your heating oil tank lines. Lines buried in the floor are usually made of steel or copper, and when they come in contact with the soil or concrete they can corrode and leak oil, going undetected for years.
By installing new copper heating oil lines encased in plastic sleeves can protect against damage and corrosion. Protect the value of your property and upgrade your fuel oil lines.
Why put the tank indoors?
Outside tanks are subject to condensation inside the tank with changing temperatures putting water into your oil creating winter service problems & eventual corrosion inside your tank.
Outside tanks require the use anti-gel additives or a kerosene blend in the winter to keep home heating fuel oil from “gelling” in extremely cold temperatures.
Granby offers a double bottom oil tank for additional safety and leak protection.
At JC Heating & Cooling we stock a complete line of fuel oil storage tanks for sales and installations. Financing is Available
If you think you like to have for an aboveground heating oil tank inspection, don’t worry just call us today at @ (215) 945-4833. Oil Tank inspections are allways free for our oil delivery customers
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Serving Levittown and the Bucks County & Montgomery County area for over 48 years. If you need a qualified heat oil contractor for your next system you come to the right place. We're proud to provide heating oil tank repairs, installation and removal to the following communities in Bucks County, PA: