In-slab air ducts are usually vulnerable to water attacks. This is because being installed in the floor usually exposes them to flood water. If they are installed below the water table, they are also vulnerable to ground water seepages. There is also the risk of attacks from water that leaks from a defective plumbing system.
All these things usually combine to form a compromised duct system whose capacity to move air is affected and which exposes the home to poor air quality – moisture encourages mold growth. The good news is that it is possible to reduce the chances of water getting into your air conditioner's duct system. The following are duct installation tips that will come in handy in helping to keep your air ducts moisture-free.
Be aware of the depth of installation
Ground water usually seeps into in-slab ductwork only when the ducts are installed below the high water table. Installing the ducts too deep into your slab will do nothing but increase the chances of water infiltration your air conditioner's air supply system. And since this water occupies space, this may reduce the efficiency with which the ducts supply air to the cooling part of the system and thus affecting the performance of your system. These are problems that can be avoided by simply installing the duct system above the high water table.
Install the duct system at a slope
When not sloped, duct systems usually encourage the accumulation of water. Stagnant water encourages bacteria infestation and mold growth. This may then contaminate the air passing through the duct system and thus reducing the overall quality of air that the air conditioning system dumps into your home.
Installing the ducts at an angle will discourage accumulation of water and any food particles. It will help reduce the rate at which pathogens and unwanted growths develop inside your system and will thus keep your loved ones safe from attacks such as mold-triggered allergic reactions.
Consider vapor barrier installation
Leaks from bust pipes and other defective plumbing system parts may introduce moisture into the concrete, insulation and gravel that surrounds the in-slab duct system. Without anything standing between the ducts and the surrounding material, saving your air conditioning system from the devastating effects of moisture-filled ductwork is almost impossible. It is for this reason that it is usually advisable for homeowners to install HVAC duct vapor barriers. Having this added layer of protection will go a long way towards keeping the indoor air quality in your home as high as possible.
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