Preventive Maintenace for Oil Furnaces
Oil Furnace Burner Do's and Don't
Flame Safely Control: If the Safely control has tripped, don't reset it more the twice. Everytime it is reset, the pump sprays fuel into the combustion chamber, if the fuel is not igniting it will build up on the bottom of the combustion chamber. Once your furnace does ignite, that buildup fuel can result in an explosion inside the furnace. This can damage the combustion chamber, vent connector, chimney, and make a complete mess of the house.
Let the oil tank run dry, when this happens the oil pump will suck in air, this air would have to be purged. The oil pump should have a bleed port
Change the Air Filters regularly.
Change the oil filter regularly.
Check the fan belt for proper tension and wear. Replace if necessary
Replace the oil nozzle annually
Properly service the equipment before the heating season
What is proper service.
Smoke Test: To set up the Air/Fuel ratio a sample of the exhaust must be tested. By drawing air through a filter paper, the colour of which allow the technician to set the air shutter. Too little air will cause shooting, reduce efficiency and restrict the heat exchanger. Too much air will reduce the combustion temperature and reduce efficiency.
Clean the Combustion Chamber: There are normally two inspection ports on the furnace. This allows access the secondary flue passage of the heat exchanger, for inspection and cleaning. This can be cleaned using a vacuum (with a good filter ) and a soft brass brush.
Barometric Draft: The swing damper on the vent connector controls the draft up the chimney. If the draft is too high, the hot flue gases will pass thorough the heat exchanger too quickly, sending the heat up the chimney. Draft should be a set a 0.02"W.C.- 0.03" W.C.with a draft gauge This is a very small amount of pressure. If the barometric damper door is sticky at all, it will not control the draft properly.
Oil Pump Pressure: The oil nozzle is design to work at 100 psi, to provide a proper spray pattern and flow rate of fuel. Higher pressures can cause the furnace to over heat, lower pressure can collapse the spray pattern, resulting in a poor flame. An accurate pressure gauge should be installed on the oil pump.
Oil Nozzle: The oil nozzle meters the flow of oil to the combustion chamber and create the proper spray pattern which controls the shape of the flame in the combustion chamber. The nozzle consist of a small opening in the tip, a spinner located behind the opening, and a brass filter. The opening can clog up very easily, the spinner will wear at the opening causing the flame pattern to change, and the brass filters can plug up. The nozzle should be change regularly. Approxmently every 500 hours of operations. A faulty nozzle is often the problem when the furnace fails to light.
Ignitor Position: The Ignitors must be in the proper position in order to light. The points should be 1/2" above, 1/8" ahead of the nozzle with an 1/8" gap. This works with most oil furnaces. Ignitor Drawing.
Oil Burner Flame Scanner
Replacement Oil Filter Cartridge