Our Process
Inside a top sealing damper job in Midway
Rain protection while the damper is open
Not every top damper is a rain cap. The Lyemance listing points out that its original damper does not extend above the flue and offers no rain protection when the damper is open, and it sells an optional cap with a screen for that purpose. Other designs build a cap into the damper.
Where a rain cap is installed, Florida's residential code (section R1003.9.3) wants the net free area beneath it to be four times the flue outlet's net free area or more. For your Midway chimney we explain whether the proposed damper covers the flue when open and price a cap separately if it does not.
Adjusting the cable for a tight seal
Once the bracket is fixed, the handle, chain and cable are threaded through it until the slack is out. The Lock-Top instructions then have the installer pull the cable to close the damper, set the adjustment clamp for the tightest seal, tighten it and cut off the excess cable.
That final adjustment decides whether the lid truly closes. Our installers close and open the damper on your Midway chimney several times after adjusting, check the lid from the roof and leave the handle set so that locking it in the bracket means the damper is shut.
A damper made for wood-burning fireplaces
Top sealing dampers are made for wood-burning masonry fireplaces, where the damper is opened for a fire and closed afterward. That open-and-close routine is what the gasket, spring and cable are built around.
A wood-burning Midway fireplace with a masonry flue in good condition is the kind a top damper suits. If it has been converted, holds a different appliance or vents something else through the same flue, our team works out the right closure for that setup instead.
More than one flue in the chimney
Some chimneys carry two or more flues, each serving a different fireplace or appliance. A top damper belongs only on the flue of a wood-burning fireplace it suits, and the other flues keep whatever their own appliances require.
Before measuring your Midway chimney, our team identifies which flue serves which fireplace, so the damper goes on the right one and nothing that must stay open is ever closed.
