How To Open Fireplace Flue Video. Simply place your hand at the top of the if the damper is stuck in a particular lubricate the damper to ensure it carries on working efficiently. Once the flue is open, place your logs, kindling and paper into the fireplace and set the fire.
If you spot condensation inside the chimney stack don't worry — this can usually be resolved by installing a suitable flue liner. If the fireplace smokes a little or occasionally, make sure the damper is in the fully open position. Calculate the flue dimensions and minimum height the sizes needed for your flue and the height of your chimney are relative to the open area of your fireplace.
If you spot condensation inside the chimney stack don't worry — this can usually be resolved by installing a suitable flue liner.
The most common case is 1⁄ 10 of the fireplace opening area, but with a minimum size specified. You can reach inside of the fireplace opening and behind the lintel to touch the damper. Review your fireplace manual or check with the brick industry association for dimension charts and formulas [source: If you're not sure which position is the open or shut, repeat step 2 to determine the position of the damper.