How Often Should the Combustion Chamber of a Waste Oil Fired Boiler Be Cleaned?

Fuels

• Waste oil boilers are designed to burn a variety of fuels, such as transmission fluid, synthetic, used oil, crankcase oil, hydraulic fluid and new fuel oils. Boiler maintenance depends, in part, on how dirty the fuel is. According to Lanair Products, a Wisconsin based company that’s been manufacturing waste oil heaters and boilers since 1976, of the fluids commonly burned, transmission fluid is the cleanest fuel while diesel truck and equipment oil is the dirtiest. A few boilers can also burn vegetable oils.

Reducing Maintenance

• You can reduce boiler maintenance if you pre-filter the oil before pouring it into the tank and clean the filters every month. In addition, you should never mix solvents or parts washer fluid in with the oil or burn gear lubes. The boiler will require more maintenance if you burn these fluids. Lanair Products recommends vacuuming ash from the combustion chamber once or twice a season.

Cleaning

• You need to clean ash residue from the heat exchanger and clean or replace the in-line oil filter at the same time that you remove ash from the combustion chamber. In addition, the burner head area, the nozzle and the flue passage need to be cleaned. Wear protective clothing when cleaning the boiler because used oil may contain heavy metal compounds that leave deposits inside the boiler and chimney.

Chimney Run

• The boiler will burn more efficiently if you don’t use horizontal chimney runs longer than 8 feet in length. Ash accumulates in horizontal runs and should be cleaned every 500 hours of use or it will block the draft and cause backpressure, oily buildup and unpredictable ignition.

Ash Accumulation

• Boilers don’t run as efficiently when ash accumulates in them. According to Professional Engineer Geoffrey M. Halley, director of technical affairs for the American Boiler Manufacturers Association, there is a 13.6 percent loss of fuel when a 1/8-inch layer of soot coats the firetubes in the boiler. In addition, the incomplete combustion that results from a reduced flow of air can lead to problems with carbon monoxide.