Critical Steps to Take When Sealing HVAC Ducts

Your home’s ductwork plays a vital role in the cooling and heating process, delivering conditioned air throughout your home. Ducts are vulnerable to damage, and deterioration can result in a significant leakage. While it’s always best to contact a professional HVAC technician when problems arise in your cooling or heating system, sealing HVAC ducts that are accessible can be accomplished by most homeowners.

Why is Sealing HVAC Ducts Important?Critical Steps to Take When Sealing HVAC Ducts

It’s all quite simple – if air is leaking from holes in your ductwork, it’s not reaching its destination in your home. This forces your cooling or heating equipment to work harder to compensate. In addition, dirty air can enter leaky ducts from unconditioned areas of your home, such as a crawlspace, basement or attic. From there, contaminated air can circulate in the air you breathe.

Sealing HVAC Ducts

Before you seal your ducts, you need to find the source of the leaks (a professional technician will need to access and seal ducts you can’t reach yourself). Look at the joints of duct sections, and where ductwork connects to the furnace or air handler. Smoke wavering from a lighted stick of incense may reveal where air is leaking while your cooling system is operating. The holes may be clearly visible.

Your sealing tools should include both quality metal-backed tape (not standard duct tape, which loses its seal in a relatively short time) and mastic sealant. First, clean the area you’ll be sealing with a damp, clean cloth. Then, evenly spread the mastic sealant over each connection or joint, making sure you use more than enough for the job at hand.

To spread the mastic, you can use your gloved fingers, a disposable paint brush or a putty knife. Then, cover the mastic with cloth or fiberglass tape. You can reverse the process – tape first, mastic second – if you’re sealing a larger leak.

This is a basic duct sealing process. For a more comprehensive duct-sealing job, contact the professionals at Hansberger Refrigeration and Electric Company. We serve the Yuma area.

Our goal is to help educate our customers in Yuma, Arizona about energy and home comfort issues (specific to HVAC systems). For more information about sealing ducts and other HVAC topics, download our free Home Comfort Resource guide.

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