True or false? When it comes to heating and cooling equipment for your home, your HVAC system itself is what's important; ductwork and vents play an insignificant role. The answer is: False! Simply put, if you install ducts and vents incorrectly, you will end up paying big bucks to heat or cool the great outdoors ... and even worse, you may put your family's health at risk. Ditto if you fail to maintain your ductwork in good shape.

Potential Problems

Reduced air distribution efficiency. Duct and vent installation is a complex business, which is best left in the hands of a reliable HVAC contractor. If it is not performed properly, the efficiency of your HVAC system, no matter how new or expensive, will be greatly reduced. The US Department of Energy reports that many American homes contain air distribution systems (that is, ductwork) which are operating at only 60-75% of capacity or less. In simple terms, that means you may be getting a lot less heating or cooling than you're paying for.

Reduced indoor air quality. If your ducts begin to leak, they allow contaminants such as bacteria, molds, and common allergens to enter the piping system. From there, the unhealthy air may be distributed throughout your home. This can cause or aggravate a number of illnesses, including infections, allergic rhinitis, respiratory problems, chronic headaches, and more.

Pressure imbalance. Leaky ductwork can also lead to pressure imbalances, which will draw outdoor air into the home and force already-conditioned air outdoors. Beyond a loss in HVAC energy, this uneven pressure has the potential to cause backdrafting of lethal carbon monoxide by fuel-burning appliances, such as natural gas heaters or wood stoves.

Vent and Duct Install

ACCA standards. Whether you are planning to install ductwork in new construction or retrofit to an older home, choose a system that was designed to ACCA (Air Conditioning Contractors of America) or equivalent standards.

Professional install. Have an experienced HVAC contractor install your air distribution system. The professionals have the know-how to follow up-to-date best practices and maintain the system's mechanical integrity.

Location. Locate ducts in a conditioned space whenever possible. This may not be feasible with a retrofit, in which case you should ensure that they are adequately insulated. R-value should be at least 8.

Sealing. The ductwork and furnace ought to be thoroughly sealed against leakage. Careful attention should be paid to joints and connections.

Vent and Duct Repair and Maintenance

Leakage or cracking. Ductwork with dark spots on its insulation is a signal that the ducts need repair or replacement, due to leakage or cracks.

Rust, twisting, tearing or crushing. Rusted, twisted, torn, or crushed pipes also call for repair or replacement of the duct system, depending on the severity of the damage.

Inadequate heat and cooling supply to one or more rooms. If only part of your house is not receiving enough conditioned air, you may want to install a second vent in the affected room(s), backed up by a flexible air duct.

Mold growth. Mold growth on your ductwork is a serious problem. Should this occur, you will need to have your ducts cleaned and possibly replaced. The source of the mold must also be dealt with to prevent recurrence.

Insect or animal pests. Insects or rodents can do damage to your duct system. They should be removed ASAP.

Dust or particles from the ductwork. Although the merits of duct cleaning are a matter of debate, it is justified in cases where visible dust and other debris particles are released into your living space from the ductwork.

Laura Firszt writes for networx.com.