Duct Maintenance And Its Effect On Heating And Cooling Costs

Buying a highly efficient furnace and air conditioner is a good first step toward improving the energy efficiency of your home, but you also need to consider your ducts. The efficiency rating for a furnace or AC unit only applies to the unit itself, but your ducts play an important role in determining the overall efficiency of your system. Thus, duct maintenance is an important part of maintaining the efficiency of your HVAC equipment. 

Leaky Ducts

Installers should effectively seal the ducts running through your home, but sealing ducts is not a one-and-done type job. As air flows through your ducts, it will create outward pressure on the joints and seams of the ducts. This combined with a constant cycle of heating, which will cause your ducts to repeatedly expand and contract, can cause your joints and seams to start leaking over time. If your ducts run inside the drywall of your home, you will have no choice but to call a duct maintenance company to inspect your ducts and repair leaks as necessary. On the other hand, if you have exposed ducts in your attic or crawl space, you can do the job on your own in this way:

1. Turn your thermostat to the "fan" position.

2. Access your ducts and then light a stick of incense.

3. Run the incense along the joints and seams in your ductwork. 

4. Mark any place where the smoke from your incense is disrupted by a leak in your ductwork. 

5. Turn your thermostat to the "off" position.

6. Paint the leaks with a thick layer of duct mastic. 

7. Allow the duct mastic to dry before you turn the thermostat back to "run."

In that leaky ducts can decrease your system efficiency by up to 40%, inspecting your ducts and repairing leaks cannot be ignored. 

Insulating Your Ducts

Your duct system should run inside the insulation envelope of your home, but you will sometimes find that your ducts run through an attic or crawlspace and are thus exposed to fluctuations in the outside temperature. For example, a hot attic will heat up your ducts, which will then heat the air flowing through your ducts and cause your AC to run longer and harder than it should. You can insulate your ducts by wrapping them with a reflective insulation material, which you can buy at a home improvement store and cut to size on your own. 

For more information, contact an HVAC contractor in your area.