Maintenance Checklist for Furnace Ductwork

man replacing HVAC duct filter

When you keep your furnace system well-maintained, you keep it running more efficiently. Ductwork that isn't receiving regular maintenance may cause your furnace system to work harder, burning more energy, which leads to higher utility bills. Good maintenance can also help you avoid furnace problems that can cost big money in repairs.

Duct Maintenance Checklist

Perform regular maintenance once a year on your furnace ductwork. It won't take long to perform a few tasks that can end up saving you money on utility and repair bills in the future.

Check for Leaks

Turn the blower on the furnace to on and inspect the ductwork with a spray bottle full of soapy water. Lightly mist the ductwork, especially at the joints, and look for excessive bubbling. Excessive bubbling means that air is escaping in that location because of a leak.

There's actually a perfect solution and an easy fix for ductwork leaks. All you have to do is cover them with duct tape. This is the actual purpose of that ubiquitous tape that everyone uses for everything other than sealing ducts. But if you have a duct leak, this is an affordable and simple fix.

Check for Clogs and Blockages

hands vacuming a circular duct

Check all vents and registers in the house. Make sure air is flowing from all the vents and check to see that they are all open. If a vent has weak or no airflow, you probably have a clog. If you think you have a clog, you need to have a ductwork cleaning performed. A professional crew will come in and clean the ducts, removing all debris.

Check for Rust

Rust spots can develop on furnace ductwork, a natural reaction to the condensation caused by the cool air inside of the ductwork reacting with the warm air outside of it. Visually inspect the ductwork for any signs of rust. If you see any rust spots, sand them down as much as possible and paint over them with epoxy-based paint that is rated for high heat.

Bigger problems develop when the rust is inside of the ducting and cannot be seen from the outside. If sanding the rust down results in breaking through the ductwork or the rust within the ductwork corrodes the wall to the point where there is a breakthrough, then it is easiest to cut out and replace that section of ductwork.

Change the Filter

man checking long filter from HVAC duct

If you have a filter, change it. The filter should be changed once a month to keep the furnace running at its peak and keep air flowing freely into your home. The filter catches dust and hair that would otherwise get into your ducts and potentially create clogs, so you want to keep changing this regularly. By 12 filters at once and you have a year supply.

Watch Your Energy Bill

Some spikes in your energy bill are normal. If you go through a cold snap or there is severe winter weather for a few days, you will see a slight increase in your monthly energy bill. But if you notice that your energy bill seems to be getting higher than usual and there is no weather-related reason for this spike, you may have developed a ductwork problem such as a leak or a clog.

If you see a spike in your utility bill, run through your maintenance checklist even if you’ve already performed your yearly maintenance. After all, problems are best caught early and fixed quickly. There’s no reason for you to pay a high energy bill for many months in a row.

Maintaining Your HVAC System

The ductwork is a huge part of any HVAC system. If there is a leak, a clog, or something that might affect the performance and efficiency of the ductwork, you could end up paying a lot more than you should to keep your home heated and air-conditioned. Regular maintenance will alert you more quickly to potential problems and help you keep everything shipshape. After all, why pay more on your utility bills than you have to?