How to Adjust a Draft Furnace Regulator

A draft regulator is typically installed on an oil furnace to allow air into the stack when the oil burner turns on. When the draft regulator opens automatically, air flows into the furnace stack to oxygenate the fire on the oil burner. Rumbling or rattling noises inside the stack are signs that the draft regulator should be adjusted for maximum fuel efficiency. If too much air flows through the draft regulator, the furnace wastes heat. Insufficient airflow causes oil to burn less efficiently.

Pliers

Instructions

- 1
  Turn on the furnace normally and set the thermostat to the desired temperature.
- 2
  Unscrew the knob on the draft regulator to loosen it.
- 3
  Slide the knob forward on the scale to widen the opening of the damper inside the draft regulator and increase airflow. Screw the knob tight. A scale printed on the side of the regulator guides your adjustments based on the manufacturer's recommendations for your particular oil furnace.
- 4
  Loosen the knob and slide it to the left to narrow the opening in the draft regulator and decrease airflow. Tighten the knob when you are finished with the adjustments.

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