How Do I Stop My Home Air Conditioning Vents From Leaking?

Identify the Leak

• First find out what type of leak you are dealing with. If the leak is water, you have a separate problem altogether. While central air-conditioning units often leak, this is usually because of clogged drains, and the water does not seep all the way through the ventilation system. If there is only a small amount of water, especially on the outside of the vent, it could be condensation cause by the temperature differences between the air inside and the air outside of the vent. If there is a definite pool or drip of water, then you likely have a more serious problem and you should look for the source of the leak. Check nearby pipes, roofs and walls to see where the water could be coming from.

  If the leak is air instead of water, this is a common vent problem and can be dealt with in two different ways. You can either replace the vents that seem to be leaking air, or reseal them to prevent air from escaping. Older vents should probably be replaced, as they will continue to develop leaks, but newer vents can be sealed.

Seal Leaks

• Begin by examining all the vents in your house, making sure they are all properly connected and there are no damaged or missing parts that need to be replaced. Isolate the areas where the leaks are coming from, so you will know exactly where to seal them. Clean that area of the vents well and wait for it to fully dry.

  Do not use duct tape to seal vents, because it will peel and disintegrate. Instead, use mastic sealant or metal tape to seal the areas you know are leaking. Pay special attention to any connections where vents meet walls or floors, as most leaks develop at these points. If you want to increase efficiency, seal all your duct work in a similar manner to prevent the development of future leaks.