• Determining Burner Pattern
• Noisy Fires
• Cold Oil
• Delayed Ignition
• Furnace Room Odors
• Smoky Fires
• Off-Center Fires
• Long Fires
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To establish the correct spray pattern, try a hollow cone nozzle with an 80 degree spray angle (a popular angle in the industry). If the pattern is not satisfactory change to a solid cone nozzle. Reducing nozzle angle in 10 degree increments from 80 degrees is a good way to find proper angle. (Mobile home units usually require 90 degree spray angles.

• If the unit is fired with a solid cone nozzle, try a hollow cone or Type W nozzle.
• If the unit is fired with a 60 degree nozzle, the noise level can be reduced in most cases by going to a wider angle.
• Check to make sure the pump pressure is properly set.
• Check the nozzle spray to be sure it is satisfactory. If the nozzle is clogged, it may be impossible to ignite the resulting spray.
• Check the spray pattern. Above 2.00 GPH, some burners give delayed ignition with the hollow cone sprays, in which case a solid cone nozzle may be the answer.
• Sometimes the next size smaller nozzle will help. Also, the smaller droplets will burn cleaner decreasing the amount of soot and dirt.
• Installing a delayed opening solenoid valve on the nozzle line can usually help pulsation during start up or shutdown.

Outside storage tanks can be a source of burner problems because oil becomes more viscous as the temperature drops. This, in turn, can result in slow ignition, collapsing sprays and noisy fires. There have been some cases where the oil was so cold it would not flow through the pipe.

Although some success with special nozzles has been reported, the surest cure for this problem is to increase the pump pressure to 120-125 psi and use the next size smaller nozzle. The extra energy from the pump will atomize the heavier oil, resulting in better ignition and a more stable flame.

Check the following items:

• Check for proper electrode setting.
• Check the insulators for cracks or for a conducting coat of soot of oil. Cracks sometimes occur under the electrode bracket, causing a short circuit.
• Check to see that the air shutter isn't too wide open.

In the case of furnace room odor, check these items:

• Check the draft over the fire and make sure it is at least .02 inches of water column. If it's lower than that, check for obstructions in the flues, or for poor chimney draft.
• Check to be sure that the unit is not being over fired.
• Check to see that there is not too much air through the burner.
• Delayed ignition also can be a cause of odors.

Smoky Fires

• Check the air handling parts of the burner. Maker sure the fan blades, air intake and air vanes in the combustion head are clean. If dogs or cats are kept in or near the furnace room, it's not uncommon to find hair in the oil burner fan.
• Check combustion chamber or the burner tube for damage. In the case of a stainless steel chamber, it might be burned through in one or more places. Or in the case of a brick chamber, some of the bricks might have become dislodged, leaving openings. Sometimes a burner end cone will be burned off or warped.
• Check the nozzle for contamination. If clogged, it could produce an off-center fire resulting in smoke.
• Going to a size smaller nozzle might eliminate smoke.

• Check to see if nozzle spray angle is too wide for the burner air pattern. In this case, smoke may form at the side of the fire. The solution is to select the next narrower spray angle.
• A solid cone spray pattern in a burner with a hollow air pattern will produce a smoky center in the fire. This can be corrected by changing to a hollow cone nozzle of the proper spray angle.
• Check for spray impingement on the walls or floor of the combustion chamber, or at the end of the burner tube. This is a cause of carbon build-up and smoky fires. It's usually corrected by the proper choice of spray angle, or by going to solid cone spray pattern. If it's at the end of the burner tube, you may have to relocate the nozzle.

• May be caused by off center location of the nozzle in the burner tube. The nozzle tube or bracket may be bent or improperly located.
• If the heavy flame always appears on the same side in a particular burner, this is due to a particularity of the air pattern in that burner and it can't be corrected by changing nozzles.
• A nozzle contaminated by sludge or other foreign matter will usually produce an off- center fire.
• A hollow air pattern will sometimes pull a solid cone spray over to one side, causing an off-center fire. This can be corrected by changing to a hollow cone nozzle.