How to Repair Duct Work
- 1). Locate the leak. It is likely that the leak is coming from the joints between sections of ducting.
- 2). Use a damp cloth to clean the area, making sure it is free from dust or grime.
- 3). Seal the leak using mastic sealant. This can either be brushed on, or you can use an applicator gun if you wish. Simply insert the mastic tube into the applicator gun and squeeze the nozzle to apply the mastic.
- 4). Cover the mastic sealant with mastic tape, completely covering both sealant and leak to ensure a tight seal.
- 5). Leave the area for a couple of hours to let it dry. Turn the unit on and inspect the area to ensure it is not still leaking.
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