What action should be taken if the initial smoke reading is zero?

When the initial smoke reading is zero, it indicates that there is no visible combustion byproduct in the flue gases. This could suggest that the combustion process is exceptionally clean or that there is a potential issue with the oil burner settings or operation. The appropriate course of action in this scenario is to take back to a trace of smoke, as this indicates that the burner is functioning properly and producing some combustion byproducts, which is necessary for verifying that the burner is operating efficiently.

Taking the reading back to a trace of smoke ensures that the burner is operational and allows for a check on the combustion process. A trace of smoke is often necessary to confirm that the burner is creating an effective balance between air and fuel for proper combustion. Adjusting the settings without verifying the air-fuel mix could lead to inefficient operation and potential safety issues.

The other actions may not be as effective in addressing the primary concern of ensuring proper combustion. For instance, taking the reading again without changing settings may not provide new information if there is an underlying issue. Increasing the oil flow rate without first confirming the need for it could lead to undesirable combustion conditions. Checking for the proper combustion air supply is important, but without first verifying that the burner can produce a trace of smoke, adjustments