How to Fix a Seal Leak on a Double-Pane Window
- 1). Locate the leak in the sealant and use a clean rag to wipe the area with denatured alcohol or an appropriate household cleaner. The surface cannot contain any loose debris that will trap air beneath the new sealant.
- 2). Cut the plastic tip on a tube of caulk so that a hole about 1/4 inch wide is created to dispense the silicone. Use the puncturing tool on a caulking gun to break the foil seal within the tube's nozzle.
- 3). Load the caulking tube into the gun; use one that features no-drip and smooth trigger action for optimal results. Grasp the front of the caulking gun with one hand, and the trigger with your other. Align its tip with the seam of the window frame where the leak is located.
- 4). Pull the trigger to dispense a bead of silicone caulk. Glide the sealant smoothly along the leak to fill the gap, then release the trigger.
- 5). Glide the back of a plastic spoon over the freshly applied caulk to level it. Allow the sealant to cure for 24 hours, or as instructed by the manufacturer.
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