Page 34

NORA Oilheat Technicians Manual

tank. They create a sludgy mess that will cause lots of no heat calls.) Biocides kill or prevent the growth of bacteria and other microorganisms. They must be fuel-soluble and must be able to sink to the water in the bottom of the tank where all the microbes live. Microbiological organisms in fuel are bacteria, molds, and yeast. Since biocides are poisons, you have to very careful. Read the label to determine product use, treatment rate, and human exposure hazards warnings. Preventative maintenance Good housekeeping means doing everything you can to minimize dirt and water from entering tanks. Water promotes the growth of microbes, which use the fuel as a food source, and accelerates the growth of sludge and internal corrosion of the tank. Water can enter the tank through cracked or leaking fill pipes and vents. They should be checked periodically and whenever water contamination is suspected. Varying air temperature and humidity can cause condensation within the tank. Dirt Chapter 2 Heating Oil 2-14 Heating Oil and Its Properties and debris are generally introduced into the fuel through careless handling. Use of rags for cleaning components The rags used for cleaning can be a source of trouble. Using a rag contaminated with sludge or microbes can introduce these contaminates to a clean system. Also, if they are of a loose weave or have frayed edges, strings or fibers, lint from these rags can get into the system and plug the nozzle. Tank cleaning With massive accumulations at the bottom and on the sides of the tank, mechanical cleaning, fuel filtration, the use of additives and a preventative maintenance program are the only way to effectively remove the sludge. Portable tank cleaning/ filtration machines are available. Their effectiveness depends upon the condition of the tank, access to the interior, and the operator’s skill. Before attempting to clean the tank, let the burner draw the oil down as low as possible to minimize the amount of fuel you will have to dispose. There are companies that offer tank-cleaning service. However, cleaning a residential heating oil tank is usually expensive and difficult, and a tank replacement may be more economical and effective. Tank replacement If the tank has gone too far, tank and fuel treatment remedies will only buy you some time. A tank’s surface contains microscopic pits and craters where bacteria can ‘hide.” Once fresh fuel is added and a bit of water condenses, the bacteria can reproduce at an astounding rate and sludge formation begins. Often, the only solution is to replace the tank and oil lines. Never pump the oil from the old tank into the new one. Figure 2-4: Tank shed covering an outdoor, above ground tank


NORA Oilheat Technicians Manual
To see the actual publication please follow the link above