How to Repair AC Duct Work

Repair AC Duct Work

Your ductwork is essential to our HVAC system for these are passages that allow airflow to maintain good indoor air quality. Sometimes, our AC unit ductwork might have some problems that we have to diagnose and solve. The most common problem would be leaks in the system causing costs to go up, waste energy, pressure imbalances, mold, rot, moisture problems, and comfort complaints. To make things easier for you, here are some tips and guidelines to help you repair your AC unit ductwork.

Locating a Leak

Observe the HVAC system in your house and try to feel if some parts feel abnormally cool or warm, if no air is coming out of vents or if your AC system blows up warm air. Sometimes, the problem might just be poor insulation but try to look for rusting or discoloration of the insulation for these might indicate a leak. Inspect if some joints in the pipes are connected properly. You can also call our HVAC contractor to run some diagnostics or do a pressurized test to look for leaks in the system. Your technician might use a “duct blaster” to aid the process.

Sealing the Leak

Once you found a leak, turn the system off and use a metallic foil tape specially designed for ductwork to cover up the gaps or holes. The best tape to use is an aluminum foil tape since it is versatile even in extreme cold and heat temperature, moisture and chemical resistant, flame resistant, and it also holds up for a very long time. You can use aluminum foil tape alone but if you have fiberglass mesh tape, you can also use it but make sure you will use duct mastic with it. Avoid using other types of adhesives since they will become loose over a short period and you will have to repair the same thing again.

Applying Duct Mastic

To help improve the seal you made, use a duct mastic sealant. Use a disposable brush or gloved fingers to apply it over the tape. Be careful and try to use old clothes when you are doing this since it is a very messy job.

Testing the System

If you want to make sure everything works perfectly, you can test the system yourself. Just inspect it the same way as you did before. Observe if the temperature is abnormal and check if your newly made seal is effective. You can also call an inspector to help run some tests for you. They will also make sure that your HVAC system passes most model codes, including the 2006 International Residential Code (IRC.) This will make sure that your system meets all the requirements and standards, and that it will work both effectively and efficiently.

All of these should make repairing your HVAC ductwork a breeze, but if you are afraid to make mistakes or do this alone, do not hesitate to call your HVAC contractor. They will surely help you!